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SMALL ENGINE FUEL SYSTEMS Small Engine Fuel Systems

1. SLIDE 119 High Pressure Oil The hydraulic supply pump is a fixed displacement axial piston pump Pump During normal engine operation pump output pressure ranges from 5 M Pa 725 psi to 23 M Pa 3335 psi Output pressure is controlled by the Injection A ctuation Pressure Control Valve IA PCV which dumps excess pressure and flow back to the return circuit Pressures for specific engine conditions are determined by the ECM During cranking pump pressure is about 5 M Pa 725 psi This was raised to 735 psi on later engines and then raised to 870 psi for the 3126B E LEGV 4801 02 188 Slide T ext R eference 9 02 3126 HEU Oil Flow a Dining Liiv Enr Oil flow to the injector The oil manifold carries the oil to a tuned fitting and individual jumper tubes for each of the injectors Oil passes through the fitting and jumper tube to the the poppet valve in the top of the injector The injector uses the oil pressure to actuate the plunger when signaled by the ECM LEGV 4801 02 189 Slide T ext R eference 9 02 HEUI Orifice PILLAR SLIDE 121 Tuned fitting The tuned fitting is critical to the operation of the hydraulic system but Pressure pulses shouldn t require any service during the life of the engine The purpose of the tuned fitting is to prevent pressure pulses caused by the injector poppet valves opening and closing from entering the rest of the system The tuned fitting also serves as a seat for the
2. 18 A diesel fuel with alow cetane number can result In A Hard starting White smoke at startup Black smoke under load B C D Fuel filter plugging E A and B F A andC The high idle adjustment can be made on the engine on a 3116 engine A True B False The purpose of transfer pump pressure is A to increase engine horsepower B to disipate the water in the fuel C to properly fill the plunger and barrel assemby D to prevent filter plugging The horsepower tolerance for a Caterpillar engine with less than 100 000 miles is A 5 B 3 C 5 3 D 7 5 As inlet fuel temperature increases A Maximum horsepower of the engine increases B Maximum horsepower of the engine decreases C Boost pressure increases D The fuel becomes more dense L E G V 4801 02 15 Test 9 02 19 Itis recommended to use fuel heaters to overcome the effects of cold weather on fuels A True B False 20 Which of the 1 1 liter governor types use four governor flyweights to control rack movement A Typel B Type 2 C Type 3 D Type 4 E Type5 L E G V 4801 02 16 9 02 Small E ngine Fuel Systems Lesson Plan 1 Pre Test M aster Select the best answer 1 Thespring force in a governor A Increases fuel rack hunting Does not affect the fuel rack B C Moves the fuel rack toward the fuel on position D Prevents rack movement E Moves the fuel rack toward the fuel off position 2
3. 25 newton meters Ona 3116 engine what injectors can you set timing on if you are at top dead center compression stroke on cylinder number 6 3116 3126 HEUI engines will not start if the injection actuation pressure is lower than 735 psi on the IA PCV A True B False LEGV 4801 02 312 Test 9 02 20 26 Pilot injection on a 3126E ends when A The barrel ball check closes B The plunger groove aligns with the spill port C TheECM briefly shuts off power to the injector solenoid D The intensifier piston bottoms out A 3126E truck engine with a rating of 175 hp 2200 is run on an engine dynamometer It produces 171 hp at its rated rom under the following conditions Fuel density 35 API 85 degrees F Fuel temperature 75 degrees F Inlet air temperature 100 degrees F Air pressure 31 Hg W hat is the corrected horsepower If the engine has 150 000 miles on it is the engine operating within its horsepower specification L E G V 4801 02 313 Test 9 02 SMALL ENGINE FUEL SYSTEMS L esson Plan 22 Final E xam Select the best answer s If the answer is false on a true false correct the question to make it true 1 Low boost pressure can be caused by D A LateTiming B 2 diesel fuel C High cetane D 42 API 60 degree F fuel 2 Raising the governor high idle rom will C A have no effect on horsepower B lower horsepower C increase horsepower D decrease set point 3 The fuel
4. 59 L esson Plan Full Load R ated G overned 1 Point where the rack screw is first in full contact with the torque spring on all engines except electronic engines 2 Point where all governed specs are achieved Set Point 1 On those engines that have it is the governor position where the rack screw is in contact with the torque spring between 10 45 2 Governed occurs 20 rom below set point 3 Set point is controlled by two features a FLS b High Idle Rack Curve 1 Overrun droop curve 2 FLS 3 FTS Horsepower Curve 1 Explain the reasons for the shape of the curve a Full load governed Insert 2100 rom as governed speed on curve b Peak horsepower c Peak torque horsepower 2 Explain the relationships to horsepower a Rack after we get into lug below FTS injection volume remains the same but fewer injections occur therefore fuel rate lowers b Fuel rate horsepower curve is established by fuel rate curve c Boost normally follows the same curve as fuel rate except when a waste gate turbo is installed 1 Waste gate provides increased boost at low rpm 2 Waste gate limits peak boost to control BM EP 3 Clamping the waste gate hose is cause for warranty revocation Torque Curve L E G V 4801 02 9 02 60 L esson Plan Full load governed torque Peak torque Explain the relationship between horsepower and torque a Torque is the twisting force coming from the engine s cranksha
5. 6 7 D 3 L E G V 4801 02 243 Test 9 02 5 The difference between governed rom and high idle rpm is called C A Governor overrun B Droop C A andB D None of the above 6 BSFC Brake Specific Fuel Consumption is the amount of fuel consumed to produce one horsepower for one minute B one hour A True B False 7 Which of the following is true concerning a 3126B E truck engine B A The injector uses a jumper tube B Theinjector has pilot injection C The injector has up to 30 000 psi injection pressure D A andB E BandC F A andC G All the above 8 Whic of the following are standard conditions for a 3126 J WAC marine engine E 35 API 60 degrees F 110 degrees F intake manifold temperature 30 5 Hg barometer A and B A and C B and C All the above omm oo 8 gt LEGV 4801 02 244 Test 9 02 9 In most cases using the 173 1530 injector seating tool group eliminates the need for using a roll burnisher when changing injector sleeves B reamer A True B False 10 The 173 1530 injector seating tool group is used on all the following engines except D 3114 and 3116 MUI 3116 HEUI 3126 HEUI 3126B E HEUI J O WwW FY LEGV 4801 02 245 L esson Plan 12 01 Small E ngine Fuel Systems Lesson Plan 17 Introduction to C 9 HE UI Fuel Systems Objectives e The student will be able to explain the operation disassembly assembly setting procedure and t
6. Fuel quality is critical to engine life and good performance Although called diesel fuel the exact mixture could be slightly different with every fill up Therefore with every fill up the engine may perform differently Fuel selection L E G V 4801 02 26 Slide T ext R eference 9 02 Preferred Fuels Diesel Fuel Fuel Oil Furnace Oil Gas Oil CATERPILLAR SLIDE 4 Preferred Fuels Caterpillar engines have the ability to burn a wide range of fuels Distillate fuels Distillate fuels are the preferred fuels for use in Caterpillar engines Those fuels are commonly called diesel fuel number 1 or 2 fuel oil Diesel fuel furnace oil gas oil or kerosene Fuel oil _ oaa E xperience has proven that the use of distillate fuels will result in as Ol maximum engine service life performance and durability Distillate K erosene fuels usually contain smaller amounts of water sulfur and sediment than Maximum life the second type of fuels permissible L E G V 4801 02 27 Slide T ext R eference 9 02 Preferred Fuels Requirement Standard Low Sulfur Cetane PC 35 min 35 min Cetane DI 40 min 40 min Water amp Sediment 0 05 max 0 05 max API 60 min max 30 45 30 45 Sulfur 0 5 0 05 Pour Point 10F below ambient temperature Cloud Point Not higher than ambient CATERPI SLIDE 5 Standard sulfur 0 5 Here are the Caterpillar specifications for preferred fuels Itis separated L ow sulfur 0 05 into two group
7. How can rated load rpm be increased A Increase the rack setting B Increase high idle C Increase fuel pressure D Increase the torque setting 3 If the A P I of the fuel is lowered the BTU content will go A Up B Down C Remain the same 4 Inthe hydra mechanical governor oil pressure is used to A Compress the governor spring B Lubricate governor parts only C Move the flyweights D Move the rack Test LEGV 4801 02 17 Test 9 02 5 The governor flyweights B A Prevents fuel rack movement B Moves the rack toward the fuel off position C Moves the rack toward the fuel on position D Does not affect the fuel rack 6 The purpose of the fuel ratio control is to C A Prevent turbocharger overspeed B Limit maximum horsepower C Eliminate excessive smoke during acceleration D To limit engine RPM until oil pressure builds up 7 What is or causes black smoke C A Unburned fuel B Worn valve guides C Overfueling D Cracked cylinder liner 8 What is or causes white smoke E A Burning oil Overfueling B C Incomplete combustion D A andC E None of the above L E G V 4801 02 9 02 18 9 Which of the following can cause excessive black smoke A B C D Advanced timing High rack setting A and B None of the above 10 Which of the following can cause a low power complaint A B C D Using 2 diesel fuel instead of 1 diesel fuel Air inle
8. Solenoid drivers in the ECM send a precisely controlled current pulse to the injector solenoid which energizes the solenoid The magnetic field L E G V 4801 02 9 02 Hydraulic oil pump Fuel transfer pump IAPCV Injector 179 Slide T ext R eference created by the solenoid lifts the poppet valve off its seat which starts the injection cycle The timing duration and current level of this pulse are controlled by logic circuits inthe ECM Fuel rate is a function of pulse duration and injection actuation pressure The hydraulic supply pump is a fixed displacement axial piston pump During normal engine operation pump output pressure ranges from 5 M Pa 725 psi to 23 M Pa 3335 psi Output pressure is controlled by the Injection A ctuation Pressure Control Valve IA PCV which dumps excess pressure and flow back to the return circuit Pressures for specific engine conditions are determined by the ECM During cranking pump pressure is about 5 M Pa 725 psi This was raised to 735 psi on later engines and then raised to 870 psi for the 3126B E The fuel transfer pump is a cam actuated single piston pump which is mounted on the rear of the high pressure oil pump Fuel system pressure is maintained between 58 76 psi during normal operating conditions under load The IAPCV is an electrically operated dump valve which closely controls pump output pressure by dumping excess pressure and flow to the return circuit A variable signal vo
9. The detent should protrude 1 25 mm to 2 25 mm when the gage block and fixture is installed correctly This will insure that the proper tension is held on the gage block while the injectors are synchronized L E G V 4801 02 9 02 Install the digital indicator Zero injector Adjust injector 131 Slide T ext R eference install Indicator SLIDE 83 Install the 1U 8869 digital indicator with contact point into the 9U 7282 indicator fixture group Remove bolt nearest to the injector to be checked and install indicator group where bolt was removed Tighten the bolt and make sure ball tip on lever of indicator group makes contact with end face of the rack bar Turn the indicator on M ake sure the indicator is set to mm Use the 128 8823 locking pliers to rotate the control assembly to shut off position U se the pliers to rotate the control assembly until the injector rack head stop pin contacts the shoulder on the injector body This is the fuel shut off position W hile maintaining this position press the zero set button on the dial indicator This defines the zero rack shut off position Repeat this sequence several times to obtain consistent results Push down and quickly and release head of injector being checked to make sure there is smooth movement of the injector rack The digital L E G V 4801 02 9 02 132 Slide T ext R eference indicator should now read 3 50 0 02 mm If an adjustment is necessary use
10. This larger surface area provides a multiplication of force This multiplication of force allows 24 M Pa 3 500 psi of actuation oil to produce 162 M Pa 23 500 psi of fuel injection pressure When poppet valve moves away from lower poppet seat high pressure actuation oil enters the unit injector the high pressure actuation oil pushes on the top of intensifier piston Pressure rises on top of the intensifier piston and the pressure pushes down on intensifier piston and plunger The downward movement of the plunger oressurizes the fuel in plunger cavity The pressurized fuel in the plunger cavity causes nozzle assembly to open When the nozzle assembly opens the fuel delivery into the combustion chamber begins A large O ring around the intensifier piston separates the oil above the intensifier piston from the fuel below the intensifier piston BARREL The barrel is the cylinder that holds plunger The plunger moves inside the barrel The plunger and barrel together act as apump Both the plunger and the barrel are precision components that have a working clearance of only 0 0025 mm 00010 inch These tight clearances are required in order to produce injection pressures over 162 M Pa 23 500 L E G V 4801 02 9 02 228 Slide T ext R eference psi without excessive leakage Note A small amount of leakage is required in order to lubricate the plunger which prevents wear The barrel also contains the PRIME spill port The PRIME spil
11. is permissible in some Caterpillar engines These engines require a special fuel system to tolerate the differences of these fuels Crude oil is oil or fuel that is not yet refined or fully refined and is basically the same as it was originally pumped from the ground Blended fuel sometimes called heavy or residual fuel is composed of the remaining elements from crude oil after the oil has been refined into diesel fuel or gasoline These elements can be combined or diluted with a lighter fuel so they can flow At times these fuels have to be heated or centrifuged to be used If crude oil or blended fuels are used additional service procedures may be required and reduced service life may be experienced L E G V 4801 02 30 Slide T ext R eference 9 02 Permissible Fuels Requirement Crude Oils Blended Fuels Cetane PC 35 min 35 min Cetane DI 40 min 40 min Water and Sediment 0 5 max 0 5 max API 60 min max 30 45 30 45 Sulfur 0 5 5 0 Pour Point 10F below ambient temperature Cloud Point Not higher than ambient temperature CATERPILLAR irk SLIDE 7 Crude oil Here are the Caterpillar specifications for permissible fuels Again itis Blended fuel Separated into two groups crude oil and blended fuel It should be noted that these fuels are allowed higher concentrations of water and W ater sediment l sediment than are the preferred fuels trace metals Sulfur content B ecause they can contain higher level
12. 02 9 02 217 Slide T ext R eference engine starts The ECM monitors actuation pressure through the Injection Actuation Pressure Sensor located in the oil manifold This is a closed loop system The ECM determines the desired pressure based on several inputs and sends a predetermined current to the IA PCV The ECM also compares the desired pressure to the actual pressure in the manifold and makes adjustments to IA PCV current levels to achieve the desired pressure OIL FLOW ENGINE CRANKING Pump outlet pressure red enters the end of the body and a small amount of oil flows into the spool chamber blue through the edge filter and control orifice in the end of the spool The electronic signal causes the solenoid to generate a magnetic field which pushes the armature to the right The armature exerts a force on the push pin and poppet holding the poppet closed allowing spool chamber pressure to build The combination of spool spring force and spool chamber pressure hold the spool to the right closing the drain ports All pump flow is directed to the oil manifold until appropriate minimum actuation pressure Is reached L E G V 4801 02 218 Slide T ext R eference 9 02 Injechon Actuation Pressure Gantrol Valve FAPEM some tia CATERPILLAR SLIDE 144 Engine Running Once the engine starts the ECM controls the current to the IA PCV to Oil flow through maintain the desired actuation pressure The Injection A ctuation IAPCV P
13. 1 piston on top L E G V 4801 02 141 Slide T ext R eference 9 02 center exhaust stroke LEGV 4801 02 142 Slide T ext R eference 9 02 Engines Timining Liv ieon SLIDE 91 Rotate crankshaft R otate the engine to top dead center of cylinder number one Always ie the larger turn the engine crankshaft with the four large bolts on the front of the oits crankshaft Do not use the eight small bolts on the front of the crankshaft pulley If the rocker arm assemblies are removed and installed prior to setting the fuel timing dimension rotate the crankshaft two complete revolutions to allow the rocker arms to properly seat on the injectors LEGV 4801 02 143 Slide T ext R eference 9 02 __ Pin Top Dead Center CATERPILLAR Engin Iraming Livero SLIDE 92 Rotate in the direction Rotate crankshaft in the direction of normal rotation until bolt goes into of normal rotation front of flywheel housing and screws into flywheel This position is top Install timing bolt dead center Check the position on the intake and exhaust valves to Confirm the position confirm that the number one cylinder is on the compression or exhaust of 1 cylinder stroke L E G V 4801 02 144 Slide T ext R eference 9 02 Pre Set indicator CATERPILLAR TE SLIDE 93 Programming the Before a check or an adjustment of the fuel timing dimension can be digital indicator made the digital indicator must be programmed to a pres
14. Additionally a speed sensitive torque cam provides torque curve shaping for specific high volume applications The governor is bench set dynamically Power is set at the rack control linkage on the cylinder head using a dial position indicator All adjustments are made on this control linkage which is sealed at the factory the governor is also sealed after bench setting and is not to be adjusted except on the governor bench L E G V 4801 02 9 02 101 Slide T ext R eference Governors Type Type Code Throttle Lever Components CATERPI Governor types T ype codes L ever types H ousings Type 1 Type 1 No Servo Type 1 or 2 Type 2 Type 2 Cast FRC Type 2 Dual HP Type 2 Dual HP Type 2 Challenger SLIDE 58 There are eight types of governors used on the 1 1 and 1 2 liter engines Each of the governors can be Identified by the type code after the serial number and specific components Type governors can be identified by a the type code A following the serial number and a spring return throttle lever Type II governors can be identified by the type code B following the serial number and a spring return throttle lever Type II governors were only used on 3114 engines and do not use a Servo for controlling rack movement Type II governors also have four flyweights Type III governors can be identifed by the type code C following the serial number Type lll governors may have a spring return throttl
15. Corrected horsepower 0 972 X 171 hp 166 hp If the engine has 150 000 miles on it is the engine operating within its horsepower specification 166 175 0 95 95 No the corrected hp is off more than 3 from rated
16. R eference 9 02 Modern Fuel Systems Improve Engine Performance Fuel Economy Emissions CATERPILLAR SLIDE 106 Performance Customer demand for increased performance and better fuel economy Fuel economy along with changing emission regulations have been a significant factor in the evolution of fuel system technology Other types of fuel systems although very reliable have their limitations and can no longer meet these demands E missions LEGV 4801 02 174 Slide T ext R eference 9 02 Fuel System Requirements Rate Control Timing Control Higher Injection Pressures CATERPILLAR TE SLIDE 107 Rate control The HEUI fuel system is capable of meeting the demands for Timing control performance fuel economy and emissions by better control of the injection process Itis able to meet these demands by controlling Higher injection So a atl i a injection rate injection timing and injection pressures pressures The rate of injection can be controlled to meet any engine condition B ecause the unit injector is hydraulically actuated rather than mechanically actuated its rate of injection does not depend on engine Speed as it does with a pump and lines group or other injectors Both the start and end of injection is electronically controlled Unlike the electronic unit injector the HEUI plunger does not move until the solenoid is energized This means that plunger movement is not limited to the speed or duration o
17. T ext R eference 9 02 Injector Installation i CATERPILLAR Le Engine Training Divison a SLIDE 132 Install injector Put clean engine oil on the injector O ring seals Put the injector in W eatherpack seal place in the cylinder head and push down on top of the injector to seat it in the bore Install a new weatherpack seal on the wiring harness and connect the wiring harness to the injector LEGV 4801 02 201 Slide T ext R eference 9 02 Jumper Tube Installation sait SLIDE 133 Install rocker arms Install the rocker arm assemblies Install flared seat Install the O ring seal in the groove on top of the injector and put the Install jumper tube flared seat in position on top of the injector Install the jumper tube Hand start the manifold end nut first and then line up and hand start the bolts on the injector end Tighten the bolts and flare nut hand tight LEGV 4801 02 202 Slide T ext R eference 9 02 Jumper Tube Torque Procedure SLIDE 134 J umper tube A special tightening procedure is required to insure the jumper tube is installation seated properly on both ends First put the 125 2583 clamping fixture Tightening procedure in place on top of the jumper tube where the injector hold down clamp normally attaches Rotate the injector in the cylinder head to align the jumper tube bolt with the hole in the clamping fixture Tighten the clamping fixture bolt to a torque of 36 N em 26 Ib
18. ThelAPCV and fixed displacement pump can maintain the desired actuation pressure regardless of variations in L E G V 4801 02 215 Slide T ext R eference 9 02 engine rom and pump flow The basic components of the IA PCV are the Body Spool Spool spring Poppet Push pin Armature Solenoid Edge filter The lAPCV operates by using a variable voltage electrical signal from the ECM to create a magnetic field in the solenoid This magnetic field acts on the iron armature and generates a mechanical force pushing the armature to the right This force is transmitted through a push pin to the small poppet valve The mechanical force trying to hold the poppet closed is opposed by reduced hydraulic pressure inside the valve trying to open the poppet This reduced hydraulic pressure will increase until the two forces are in equilibrium The more current supplied to the solenoid the higher the resultant hydraulic pressure Less current results in lower pressure The reduced pressure inside the valve is combined with spring pressure and acts on the spool to push it to the right and close off the drain ports Pump pressure acts on the other side of the spool to push it to the left and open the drain ports These hydraulic forces also reach equilibrium The net result is that pump pressure is controlled by the electrical signal to the solenoid OPERATION ENGINE OFF The illustration above shows the position of the spool
19. Training Divison SLIDE 197 Fuel settings The adjustment of the fuel settings can be done with the housing for the fuel injection pumps either on or off the engine We show the procedures with the housing off the engine L E G V 4801 02 285 Slide T ext R eference 9 02 Remove Solenoid A j P SLIDE 198 Remove shutoff Remove the fuel sutoff solenoid This step is necessary to permit full solenoid movement of the fuel control linkage in the governor while making the fuel setting adjustments LEGV 4801 02 286 Slide T ext R eference 9 02 Low idle Screw amp Torque SLIDE 199 Install pin Select the correct zero set pin The 5P0298 pin with 17 8507 stamped on the large diameter is the correct one for the fuel setting on vee type pumps Put the pin into the hole in the housing L E G V 4801 02 287 Slide T ext R eference 9 02 Fuel Adjustments o O CATERPILLAR 5P4226 Adapter pin Place the 5P4226 adapter over the zero set pin Do not use a gasket under the adapter or cover Install the bolts and fasten the adapter to the housing Install the 8S7271 set screw in the adapter Tighten the set screw until the pin is held against the injection pump housing L E G V 4801 02 288 Slide T ext R eference 9 02 Tooling installation SLIDE 201 High idle position M ove the governor control to the high idle position and lock it Here the governor control is held in the high idle position by using the
20. a test on each type of nozzle LEGV 4801 02 306 L esson Plan 12 01 SMALL ENGINE FUEL SYSTEMS L esson Plan 22 Final Test and C lass E valuation Objectives e The student will take a final test to review and test the course material A minimum of 70 accuracy is considered acceptable Literature Needed Final Test Copy Course Evaluation Sheet Copy H ardware Needed None Time R equired 1 5 Hour Tasks R equired by Instructor to M eet O bjectives 1 Ask students for questions regarding material covered the previous day 2 Answer all questions using reference material Be sure the students follow along in their reference material while the question is answered 3 Administer Final Test 4 Review Final Test again using reference material to answer questions 5 Have the students fill out the course evaluation L E G V 4801 02 307 Test 9 02 SMALL ENGINE FUEL SYSTEMS L esson Plan 22 Final E xam Select the best answer s If the answer is false on a true false correct the question to make it true 1 Low boost pressure can be caused by A LateTiming B 2 diesel fuel C High cetane D 42 API 60 degree F fuel 2 Raising the governor high idle rom will A have no effect on horsepower B lower horsepower C increase horsepower D decrease set point 3 The fuel system on a 3208 is uses a A scroll type B mechanical unit injector C electronic unit injector D sleeve meterin
21. check the timing again This makes sure that the timing is correct LEGV 4801 02 275 Slide T ext R eference 9 02 Check Housing Pressure Cranking Speed 2 psi Low Idle 18 psi Full Load Speed 30 psi a SLIDE 188 Fuel housing pressure One of the fuel system checks is the housing fuel pressure This is normally done in chassis at rated speed If the housing is checked on the fuel injection test bench checks should be made at three different speeds cranking low idle and rated speeds to be sure that the engine is operating properly L E G V 4801 02 9 02 CATE 0 60 psi pressure gauge 276 Slide T ext R eference Gage Installation AR a SLIDE 189 Remove the plug on the top of the housing Install a fitting and a 0 60 psi pressure gauge Start the engine and bring it to normal operating temperature Record the pressure reading at rated soeed Compare this number to the specification in the service manual L E G V 4801 02 277 Slide T ext R eference 9 02 Set Point Check m amp a usA CATERPI Eng nz ii SLIDE 190 To check set point of the engine attach a multitach set point indicator to the engine The continuity screw is shown here with an indicator light attached to it instead M ake sure that any paint is removed from the brass terminal prior to running the test With the tool in place run the engine until it is at operating temperature Bring the engine to high idle and load
22. from standard affects available hp CATERPILLAR SLIDE 50 All Caterpillar engines are tested to SA E J 1995 conditions A tolerance of 3 is held This tolerance is held when all operating conditions are standard 110 degree F Inlet M anifold Temperature ATAAC 77 degree F Inlet M anifold Temperature Non ATAAC 30 5 Hg Barometric Pressure 29 62 Hg in factory test conditions 35 API Fuel 85 degree F Fuel Temperature This form of testing is used by all of the OEMs with slightly different Operating conditions Any deviation from the standard condition affects the engine s available horsepower LEGV 4801 02 83 L esson Plan 9 02 Small E ngine Fuel Systems Lesson Plan 7 Quiz 1 Objectives e The student will take a quiz to review and test the previous day s material A minimum of 70 accuracy is considered acceptable Literature Needed Quiz 1 Copy H ardware Needed None Time R equired 0 5 Hour Tasks R equired by Instructor to M eet Objectives 1 Ask students for questions regarding material covered the previous day 2 Answer all questions using reference material Be sure the students follow along in their reference material while the question is answered 3 Administer the Quiz 1 4 Review the Quiz 1 again using reference material to answer questions L E G V 4801 02 84 Test 9 02 Small E ngine Fuel Systems Lesson Plan 7 Quiz 1 Select the best answer If the answ
23. housing of the governor It is a piston type pump actuated by an eccentric on the governor drive shaft and driven by the governor gear L E G V 4801 02 95 Slide T ext R eference 9 02 shut Off Solenoid SLIDE 53 Shutoff solenoids A latching solenoid with two coils and a mechanical latch is installed on L atching this governor The solenoid is energized to latch and then de energized Itis energized again to release the latch It also has manual latch and release functions to provide limp home and manual shutoff Capabilities 12 or 24 volts Solenoids are available for 12 and 24 volt applications Also some applications trucks and gen sets will use a conventional non latching energize to run solenoid to allow automatic shutdown systems to shut off the engine by interrupting power to the solenoid The spanner wrench 9U 5120 shown is necessary for solenoid removal L E G V 4801 02 96 Slide T ext R eference 9 02 1 1 1 2 MUI SLIDE 54 Unit injectors The fuel injection system for this engine is a mechanical unit injector Fuel lines type The fuel injection pump and nozzle are combined in one injector assembly for each cylinder All high pressure lines are eliminated Fuel lines consist of supply lines to and from the cylinder head fuel filter and fuel transfer pump Fuel is supplied to each injector by an internal passage running the full length of the head Each unit injector h
24. intensifier hits the bottom of its bore This would be maximum fuel delivery The distance from the bottom of the intensifier to the bottom of its bore is a controlled distance to limit maximum fuel delivery This feature is called Stroke Limiting It prevents electronic tampering from increasing maximum fuel delivery beyond maximum intended fuel rates L E G V 4801 02 208 Slide T ext R eference 9 02 CATERPILLAR SLIDE 139 Return cycle The end of the injection cycle begins when the ECM terminates the current to the solenoid The magnetic field of the solenoid collapses and is no longer able to overcome poppet spring tension to hold the poppet off its seat The poppet closes shutting off high pressure oil from entering the injector W hen the poppet is seated the upper land of the poppet opens the poppet cavity to drain Pressurized oil in the intensifier chamber and poppet chamber can now flow upward around the poppet seat through the vent holes in the poppet sleeve and out the adapter drain hole The pressure of the fuel in the plunger cavity and the plunger return spring exert an upward force on the plunger and intensifier As the pressure of the downward force on the intensifier decreases The upward force from the pressurized fuel and spring almost instantly becomes greater than the downward force on the intensifier so the downward motion of the intensifier and plunger reverses L E G V 4801 02 9 02 VCP 2700 L owe
25. it until set point rom is displayed Repeat the test 5 times and average the results to obtain a proper set point rom Compare this rom to the specification found on the engine data plate If the plate is missing consult SIS SIS Web or AIMS LEGV 4801 02 278 Slide T ext R eference 9 02 Check Valve SLIDE 191 Removal of fuel To remove the fuel injection pumps first disconnect the fuel supply and injection pumps bypass lines from the fuel injection housing Drain the fuel from the housing and plug all openings Some of the earlier housings require the fuel to be pumped or siphoned out Remove the check valve flange bolts and check valve flanges The check valve maintains system pressure to a maximum of 30 psi at full load It is a constant metering valve that sends about 9 gallons per hour back to tank No return flow exists until 8 3 psi has been obtained in the housing The return allows removal of entrained air and fuel cooling LEGV 4801 02 279 Slide T ext R eference 9 02 Bypass Valve SLIDE 192 Remove cover Remove the bolts that hold the cover to the pump housing and lift off Remove valve and the cover Remove the bypass valve and spring spring LEGV 4801 02 280 Slide T ext R eference 9 02 _Lever Set Screws SLIDE 193 M oving the levers Do not loosen the screws that hold the levers to the fuel control shaft changes calibration when removing or installing the pump assemblies If the levers
26. low idle screw L E G V 4801 02 289 Slide T ext R eference 9 02 Install Indicator SLIDE 202 Assemble the 3P 1567 dial indicator by installing a 57 15 mm 2 25 inch 5P6531 contact point onto the dial indicator and put it into the 3P1565 collet clamp Install the collet clamp tighten and zero the indicator L E G V 4801 02 290 Slide T ext R eference 9 02 Turn Out Screw SLIDE 203 Use the T handle 5P4205 wrench and turn the zero screw out counterclockwise six or more complete turns M ake sure the dial indicator moves freely as the set screw is turned Then move the governor control lever to the low idle position It may be necessary in some intances to adjust the low idle screw for freedom of indicator travel LEGV 4801 02 291 Slide T ext R eference 9 02 Check PLS CATERPILLAR Engin Tirmining Livia SLIDE 204 FLS check Connect the clip of the 854627 circuit tester to the contact spring of the torque spring Fasten the point of the circuit tester to a good ground on the housing and slowly move the governor control lever toward the high idle position until the circuit tester just comes on At the exact time the tester comes on take the reading on the dial indicator Repeat this procedure several times to make sure the reading is correct The indicator reading at this point minus the recorded zero reading is the fuel setting If the setting is not correct an adjustment must be made LE
27. points not on the slide program The expense of fuel relative to other engine operating costs Fuel contaminants The effects of poor fuel quality on the engine Charts of acceptable limits and problems and causes Precombustion vs Direct Injection Fuel system maintenance gt mn moop sk if there are any questions and review any areas that might be unclear L E G V 4801 02 23 Slide T ext R eference 9 02 Small Engine Fuel Systems CATERPILLAR TE SLIDE 1 During this course we will be discussing various types of fuel systems used on our medium duty Caterpillar engines Before we can discuss various fuel systems we must first talk about what they pump Fuel L E G V 4801 02 24 Slide T ext R eference 9 02 Fuel Selection CATERPILL p SLIDE 2 Attributes of fuel We will discuss the attributes of fuel and how it affects the performance E ngine performance of a diesel engine M any people think that all fuel is the same and that it does not change engine performance The inverse is probably more correct During the next few minutes we will explore some of the differences that can be found in different fuels L E G V 4801 02 25 Slide T ext R eference 9 02 SLIDE 3 Service life Caterpillar wants its customers to get the maximum service life from Performance their engines with a minimum of downtime One method to assure good continuous engine performance is to select the best available fuel
28. spring force determine the location of Spring pack the riser Governor spring Riser L E G V 4801 02 9 02 104 Slide T ext R eference Governor CATERPILLAR Riser lever Pivot shaft T orque cam Governor output shaft Speed changes T hrottle lever SLIDE 60 The riser moves the riser lever which rotates the pivot shaft and torque cam red The torque cam moves the torque lever orange to adjust the governor output shaft blue The operator selects the desired speed through the throttle lever shown in the previous slide The throttle lever and governor output shaft are connected by the fulcrum lever which is pinned to the pivot lever This connection provides the operator with a direct communication to the governor output As the engine speed changes the fulcrum lever moves to change the governor output to a new stable condition The same condition occurs when the operator changes the position of the throttle lever The governor limits the fuel injected into the combustion chamber when rated load or a lug condition is reached When this condition occurs the Output shaft is in the maximum FUEL ON position The torque lever has rotated about a pin on the limit lever until the torque lever contacts L E G V 4801 02 105 Slide T ext R eference 9 02 the torque cam If more load is applied to the engine in this condition engine speed will decrease This decrease will be felt by the flyweights causing the r
29. stop screw is the one shown lower in the picture while the L ow Idle screw low idle screw is the upper one LEGV 4801 02 124 Slide T ext R eference 9 02 Injector Synchronization CATERPILLAR liv ion SLIDE 77 Injector Injector synchronization is the setting of all injector racks to a reference synchronization position the No 1 injector This ensures each injector delivers the R eference position Same amount of fuel to each cylinder This is done by setting each injector rack to the same position while the control linkage is in a fixed position called the synchronizing position The control linkage is at the synchronizing position when the injector of the No 1 cylinder is at 3 5 mm which is set with a positioning block Since the No 1 injector is the reference point for the other injectors no synchronizing adjustment is made to the No 1 injector Always synchronize an injector when it has been removed and reinstalled or replaced If the No 1 injector is reinstalled or replaced all injectors must be synchronized Number 1 cylinder LEGV 4801 02 125 Slide T ext R eference 9 02 Remove Solenoid SLIDE 78 Shutoff solenoid To synchronize the fuel injector rack either pull out and latch the center rod of the solenoid or remove the solenoid This allows the injector rack control linkage to move freely during synchronization LEGV 4801 02 126 Slide T ext R eference 9 02 Remove Valve Cover CAT
30. the 1U 6673 wrench and turn set screw until indicator reads 3 50 0 02 Tighten the locknut while holding set screw in position The valve clearance and fuel timing should be checked after installing the rocker arm assembly LEGV 4801 02 133 Slide T ext R eference 9 02 Fuel Setting CATERPILL SLIDE 84 Fuel setting Fuel setting is the adjustment of the fuel setting screw to a specified Fuel setting screw position with reference to the number one rack The fuel setting screw limits the power output of the engine by setting the maximum travel of number one injector and then hence all the injector racks to control maximum fuel flow Before the fuel setting is checked the injectors should be correctly synchronized or a badly synchronized could cause binding of the rack actuation mechinism Injectors should be synchronized L E G V 4801 02 134 Slide T ext R eference 9 02 Remove Sleeve p v WH SLIDE 85 Fuel setting Fuel setting adjustment using the 128 8822 tool group adjustment using the 128 8822 tool group To make the fuel setting adjustment using the 128 8822 tool group remove the clip that keeps the sleeve in position between governor and inlet manifold Using the 6V 6006 pliers slide the sleeve from governor toward the inlet manifold Do not use hard jawed pliers or a screwdriver to move the sleeve Damage may result to the sleeve which may damage the wiper seal in the inlet manifold when the sl
31. threads cut into the top of the sleeve LEGV 4801 02 223 Slide T ext R eference 9 02 3126B E Cylinder Head Cut ii Ta PIT 4 i en m in h il CATERPILLAR TEN SLIDE 148 3126B E HEUI Unit The 3126B E H1300 unit injector does not use jumper tubes for oil Injector supply The oil is supplied directly to the middle portion of the injector H1300 Angled and is sealed by two seal rings The unit injector has a top mounted Does not useajumper SO0 enoid The wiring harness has shared commons between injectors 1 tube design amp 2 3 amp 4 and5 amp 6 Theinjector also has a connector for easier removal and installation of the wiring harness L E G V 4801 02 9 02 224 Slide T ext R eference 3126B E Fuel Filter Base F uel filter location Hand priming pump standard High Pressure Oil Pump Slight increase in pump displacement IAPCV relocated for easier access SLIDE 149 With the 3126B E the intake manifold was been moved to the left side of the engine the fuel filter was been relocated to a higher location With this change we have easier access for filter replacement With the introduction of the model change we recieved the addition of a hand priming pump The hand priming pump is standard on most models The HEU pump looks a bit different with a squared top instead of rounded and has a slight increase in pump displacement The lAPCV was been moved to
32. with the engine off With no hydraulic pressure the spring pushes the spool all the way to the right closing off the drain ports L E G V 4801 02 216 Slide T ext R eference 9 02 Injection Actuation Pressure Control Valve APCV Cage AMK e a tat reed eet P EE ed haa Ei Bratt AEE ET Era as TES Masui eres ute CATERPILLAR SLIDE 143 Engine cranking In first production engines approximately 5 M Pa 725 psi of oil 5 MPa 725 psi pressure is required to fire the injector during start up This was later required to start increased to 735 psi and then to 870 psi for the 3126B E This low actuation pressure generates a very low injection pressure The low injection pressure causes the nozzle check to open and close rapidly putting small squirts of fuel into the combustion chamber which aids starting Pressure sensor ECM determines pressure Oil flow through IAPCV In order to start the engine quickly the actuation pressure must rise quickly Since the pump is being turned at engine cranking rom pump flow is very low The ECM sends a strong current to the IA PCV solenoid to hold the spool closed and block all flow to drain until the appropriate minimum actuation pressue is reached The injectors are not fired until the appropriate minimum actuation pressue is reached Once the injectors begin to fire the ECM controls the current to the IAPCV to maintain appropriate minimum actuation pressue until the L E G V 4801
33. 0 Literature Needed Analyzing Fuel Nozzle and Fuel Line Failures SEBD0639 H ardware Needed None Time R equired 1 5 Hour Tasks R equired by Instructor to M eet Objectives 1 Using Analyzing Fuel Nozzles and Fuel Line Failures explain the following A Capsule Nozzles 1 PC Nozzles a Single orifice flat nose b VOP Valve Opening Pressure 1 Test Stand 400 750 psi 2 Onengine 1500 2000psi c Peak pressure 6000 7000 psi d Uses a screen for final filter 2 DI Nozzles a Multiple orifices spherical nose LEGV 4801 02 303 L esson Plan 12 01 b VOP 2400 3100 psi c Peak pressure up to 10000 psi d Uses a screen for final filter 3 Failure modes a Bulged fuel nozzles 1 Torque a Over torque b Under torque 2 Overheated engine b Tip erosion c Cracked case d Damaged tip 1 Wire brush 2 External force B Pencil Nozzles 1 Used mostly on 3208 2 Purchased nozzle 3 No final filter in the nozzle 4 Failure modes a Tip damage 1 Wire brushing 2 External force 3 Tip break b Broken spring c Compression seal or teflon seal overheat d Ferrule damage C Fuel line adapters 1 Used to bring the fuel line under the valve cover 2 3208 adapter has an edge filter L E G V 4801 02 12 01 304 L esson Plan 3 Other models have the final filter in the nozzle 4 Fuel leaks are routed out through a small hole 5 Oil leaks could be failed o ring D 7000 Series Nozzles 1 Usage a P
34. 1 02 272 Slide T ext R eference 9 02 Install Puller SLIDE 185 5P2371 Puller Plate Remove the bolt using a deep socket wrench Using the 5P2371 Puller Plate lossen the drive gear from the tapered drive of the injection pump camshaft CAUTION Use this puller to prevent damage to the camshaft of the injection pump and the shield for the flyweights in the governor and the housing Turn the bolts evenly a little at a time to push the camshaft drive from the drive gear LEGV 4801 02 273 Slide T ext R eference 9 02 _Pin Engins TDC anen r is f CS 3 S SLIDE 186 Turn the crankshaft Here we see the drive gear loose on the camshaft of the injection pump clockwise The timing pin is in the groove of the camshaft Now we can adjust the timing of the crankshaft to the fuel injection pump Turn the crankshaft 90 degrees or more counterclockwise to be sure all clearance is out of the timing gears Then turn the crankshaft clockwise until the timing bolt goes into the valve camshaft gear The timing of the fuel injection pump to the engine is now correct LEGV 4801 02 274 Slide T ext R eference 9 02 Torque Tach Drive SLIDE 187 Correct torque W hile the timing pin and the timing bolt are installed turn the tachometer drive bolt with the washer into the end of the camshaft Tighten the bolt to the correct torque specification Remove the timing bolt and timing pin Turn the engine crankshaft two revolutions and
35. 2 158 L esson Plan 9 02 Small E ngine Fuel Systems L esson Plan 13 1 1 and 1 2 Governor Test Stand Lab Objectives e The student will be able to demonstrate the ability to properly set a 1 1 and 1 2 Liter Engine governor using the 1U 7326 Governor Calibration Bench and proper literature Literature Needed Service M anual 3114 3116 and 3126 Engine Governors SENR 6454 Hardware Needed 1 1 or 1 2 Liter Engine Governor 1U 7326 Governor Calibration Bench 1U 9786 Calibration Pin 1U 6673 FRC Adjustment Wrench 1U 9893 Solenoid Spanner Wrench 6V 6106 Dial Indicator 1U 8815 Contact Point 15 psi Air Supply Time R equired 2 25 Hours Tasks R equired by Instructor to M eet O bjectives 1 Using the 1U 7326 Governor Calibration Bench cover the steps involved in setting a 1 1 1 2 governor 2 Have the students look up the Governor Performance data in TM I 3 Have the students conduct all required tests and settings on a governor 4 Answer any questions the students have about the checking or setting procedure LEGV 4801 02 159 L esson Plan 9 02 Small E ngine Fuel Systems Lesson Plan 14 1 1 amp 1 2 HEUI Fuel System Injector Sleeve L ab Objectives e Thestudent will be able to remove and install an injector sleeve from a 3126 abd 3126B E cylinder heads Literature Needed Using the 127 3458 SleeveR eplacement Tool Group SEHS9120 H ardware Needed 3116 or 3126 and 3126B E Engines Hand Tools 127 3458 Sle
36. 220 Slide T ext R eference 9 02 HEUI Schematic Se gn Bo pn en Bn Be it on g sHigh Pressure Oil Suction Drain m Fuel Pressure CATERPILLAR SLIDE 145 Again we look at the schematic of the 3126 HEU I to review it prior to looking at the 3126B E schematic L E G V 4801 02 221 Slide T ext R eference 9 02 High Promus CE Mardi g i J T l Fuel Filter Sa a l J HEV IMJECTORS Cal Reiurn To Suma arem 7 Jump r CATERPILLAR RT aT Little Schematic With the 3126B E the schematic looks a bit different but it is the same Change in principle The major difference is the elimination of the jumper tubes that supply oil to the injector The oil supply now comes through the cylinder head L E G V 4801 02 222 Slide T ext R eference 9 02 3 Valve Cylinder Head CATERPILLAR Now let s discuss the changes that came with the 3126B E product The 3126B E doesnot have the brass injector sleeve It uses a stainless steel replaceable sleeve This sleeve is similar to the C 10 and C 12 injector sleeve The stainless steel injector sleeve replacement is easier and faster The entire process for sleeve replacement is described in the Disassemble and Assemble manual for sleeves without the threads cut in to the sleeve itself Some of the engines were built with this style sleeve A new design sleeve has been released which already has the
37. 35 API 60 degrees F D 33 API 30 degrees F W hat Is the corrected API for 43 API 110 degrees F 38 6 API 60 degrees F Fuel timing is checked on a 3116 engine using the 8T 5300 Timing Indicator Group B 128 8822 Tool Group A True B False W hat Is the proper torque for the sleeve screw on the 3208 fuel pump C A 2 8 foot pounds B 2 8 inch pounds C 25 inch pounds D 25 newton meters Ona 3116 engine what injectors can you set timing on if you are at top dead center compression stroke on cylinder number 6 1 2 and 4 3116 3126 HEUI engines will not start if the injection actuation pressure is lower than 735 psi on the IA PCV A A True B False L E G V 4801 02 318 Test 9 02 25 20 Pilot injection on a 3126E ends when B A The barrel ball check closes B The plunger groove aligns with the spill port C TheECM briefly shuts off power to the injector solenoid D The intensifier piston bottoms out A 3126E truck engine with a rating of 175 hp 2200 is run on an engine dynamometer It produces 171 hp at its rated rom under the following conditions Fuel density 35 API 85 degrees F Fuel temperature 75 degrees F Inlet air temperature 100 degrees F Air pressure 31 Hg W hat is the corrected horsepower Corrected API 33 1 API 60 degrees F 0 992 Fuel temperature 0 990 Air temperature 0 993 Air pressure 0 997 Total correction factor 0 992 X 0 990 X 0 993 X 0 997 0 972
38. 4 1 1 1 2 Injector Sleeve Lab 12 45 2 30 B reak 2 30 2 45 15 Introduction to 1 1 1 2 HEU I Fuel Systems 2 45 4 00 Thursday Introduction to 1 1 1 2 HEUI Fuel Systems 8 00 8 45 16 Quiz3 8 45 9 15 B reak 9 15 9 30 17 Introduction to C 9 HEUI Fuel System 9 30 11 15 Lunch 11 15 12 00 18 Introduction to 3208 Fuel System 12 00 1 00 19 3208 Lab 1 00 2 30 B reak 2 30 2 45 19 Intro to Fuel Lines amp Nozzles 2 45 4 00 Friday Intro to Fuel Lines amp Nozzles 8 00 8 15 20 Nozzle Test Lab 0 15 9 15 B reak 9 15 9 30 20 Nozzle Test Lab 9 30 10 00 23 Final and Course Evaluation 10 00 11 30 LEGV 4801 02 5 Small E ngine Fuel Systems Literature L ist Registration Form Small Engine Fuel System Schedule Glossary of Terms Pre Test Fuel Selection Slide Script Diesel Fuel and Your Engine Engine Performance Reference Blending Used Crankcase Qil Blending Used Crankcase Oil for use with Cat HD Diesel Engines Basic Governor Theory Slide Script Power Curve Slide Script Test Condition Slide Script Sample OT 2T Information from the TM I SIS or SIS Web Sample Engine Performance Information from the TM I on line system Quiz 1 1 1 Liter Fuel System Slide Script Systems Operation T amp A 3114 3116 3126 Engines Torque Specifications Using the 128 8822 Tool Group on 3114 3116 amp 3126 Engines Service M anual 3114 3116 3126 Engine Governor Quiz 2 Using the 143 2099 Sleeve Replacement Tool Group 1 1 and 1 2 HEU Fuel System Slide
39. Adjusting B Governor Performance Data C Disassembly and Assembly D Engine Information Plate The set point for a 3116 truck engine is 20 rom above rated speed B There is no set poing on a 3116 governor settings are made on a bench A True B False A 3116 engine shows a timing dimension of 63 56 on the engine plate When using the 128 8822 Injector Tool Group the setting on the dial indicator when on the fixture would be A A 62 00 mm B 1 56 mm C 63 56 mm D 1 56 mm The throttle stop on a 1 1 liter governor works exactly like a high idle screw on other engines B This setting also can change fuel rate A True B False LEGV 4801 02 157 Test 6 02 10 The throttle lever orientation should be checked on Type 1 2 and 3 governors before Lk 12 making any other governor adjustments B T hese governors do not have type ll throttles which are press on A True B False If an engine was producing 597 pound feet of torque at 2200 rom how much horsepower would it be producing 250 597 X 2200 5252 How much horsepower would you expect from a 210 hp 2200 3126E truck engine if it was using 39 API 55 degrees F fuel 67 degrees F fuel temperature 101 degrees air temperature and 28 56 Hg barometric pressure Would this custormer probably complain of a power problem Why 39 4 API 60 degrees F 208 5 21 1 019 X 0 982 X 0 994 X 1 013 No less than 15 hp loss LEGV 4801 0
40. E ngine Service Training Instructor Course Book LEGV 4801 02 September 2002 CATERPILLAR ENGINE COURSE BOOK SMALL ENGINE FUEL SYSTEMS L E G V 4801 02 C ourse Description Content Audience R eferences Da 02 COURSE DESCRIPTION Small Engine Fuel Systems 4 1 Days 2050 None This course is an in depth study of the Caterpillar fuel systems for the 3114 3116 3126 3126B E C 9 and 3208 engines Participants will learn to test and adjust the 1 1 and 1 2 liter mechanical and HEU fuel systems and the sleeve metering fuel system used on the 3208 engines Caterpillar fuel injection pumps governors unit injectors and nozzles will be studied e Explain the relationship of horsepower rack boost fuel rate torque and BSFC e Explain the engine operating tolerances and the relationship of density of fuel and air to engine performance e Explain the operating principles of the mechanical unit injectors HEU fuel systems and sleeve metering fuel systems e Demonstrate the adjustments of 1 1 liter and 3208 governors Demonstrate the removal and installation of a 1 2 liter HEU injector and Injector sleeve e Test 7000 series capsule and pencil nozzles e Check and adjust fuel settings e Check and adjust unit injector synchronization and timing e Explain the operation of the C 9 fuel system Students attending this course must be able to use the service manual and Caterpillar fuel system tools Participant
41. ERPILLAR Engine Trmining L Hv becorn SLIDE 79 Preparation for To prepare for injector synchronization remove the valve cover and synchronizing the rocker arm assemblies for No 1 unit injector The injector injectors ee l J synchronization can be done with the rocker arm assemblies removed or Rocker arm left in place assemblies If the rocker arm assemblies are removed be sure to hold the assemblies together Only one end of the rocker arm assembly is pinned to the rocker stand L E G V 4801 02 9 02 Rack 127 Slide T ext R eference Actuation CATERPILLAR SLIDE 80 Each injector rack is activated by a rack control assembly All of the injectors need to be equal with their injector or the engine would run rough This is done by adjusting all of the injectors to the to the same rack position as the number 1 injector This procedure is called rack synchronization Each of the injectors actuation mechinism has an adjusting screw except the number 1 which is the master of the group Number 1 injector is set and locked to a Known rack position and the rest are then adjusted to that position The number one injector is linked to the governor using the fuel setting procedure covered later in the presentation LEGV 4801 02 128 Slide T ext R eference 9 02 E i Install Injector Clamps CATE SLIDE 81 Install spring If the rocker arm assemblies are removed install the 1U 6675 spring PP
42. F L E G V 4801 02 34 Slide T ext R eference 9 02 Cloud Point CATERPILLAR SLIDE 11 Cloud point At low temperatures any fuel may contain solid particles of wax which W ax content could plug the filters rapidly The cloud point of fuel is the temperature at which some of the heavier paraffin components wax start to form crystals This is a natural process as the temperature is causing the fuel Temperature to begin its change from liquid to solid These wax crystals give the fuel a cloudy appearance This wax is not a contaminant but is an important element of diesel fuel and has a high energy content and a very high cetane value The cloud point of the fuel is important because this wax can plug the fuel filter Filter pluging If the cloud point of the fuel is lower than the lowest ambient temperature at which the engine will be expected to start and operate filter plugging will not be a problem L E G V 4801 02 9 02 CATE Pour point Minimum temperature that fuel will flow About 100 F below cloud point 35 Slide T ext R eference Pour Point SLIDE 12 The pour point of a fuel is an indication of the minimum temperature at which the fuel will flow At the pour point temperature the amount of wax crystals increases to a point where they connect together This can restrict the flow of fuel from the tank to the engine transfer pump but if the fuel stays around the fuel pick up tube the transfer pum
43. FC published in sales literature are only full load BSFC b Best BSFC usually occurs below full load speed due to improved efficiencies in the engine c Itis best to run part throttle if possible for better fuel economy 2 Fuel Rate Measured in gallons per hour a Fuel rates published in sales literature is only full load rates b Fuel rate BSFC X hp Fuel Density pounds per gallon 2 Answer any questions the students have about performance curves L E G V 4801 02 62 Slide T ext R eference 9 02 POWER CURVES High Idle Hi idle Maximum revolutions of the engine with no load High Idle 2262 RPM CATERPILL at a SLIDE 32 High Idle High idle is the maximum engine speed that can be achieved with no load on the engine as it is installed This will vary with different paracitic loads The high idle shown on the engine data tag is a bare engine high idle before any extra devices such as alternators power steering pumps etc have been installed Normal tolerances for a heavy duty high idle is 40 80 rom The high idle screw is a stop for maximum deflection of the governor spring which when multiplied by spring rate would give a governor spring force L E G V 4801 02 63 Slide T ext R eference 9 02 POWER CURVES Droop Droop Available engine rpm above governed with limited power Governed speed 2100 High Idle 2262 CATERPILLAR LFY Geom SLIDE 33 Droop Droop is the engine rom ab
44. Fuels that meet ASTM for low sulfur must contain no more than 0 05 sulfur by weight A new fuel specification is now available This has only 0 015 sulfur by weight and will be required for on highway engines in about 2007 This does not mean that every fuel will meet this specification In fact fuels with sulfur content in excess of 0 5 have regularly been found in field surveys Caterpillar engines can burn these higher sulfur fuels However to use fuels with sulfur content greater than 0 5 you have to take extra precautions to protect the engine from corrosive wear L E G V 4801 02 41 Slide T ext R eference 9 02 When You Buy Fuel Meet Caterpillar Specifications Keep it Clean SLIDE 18 Fuel selection is Clean fuel meeting Caterpillar s fuel recommendations promotes important maximum engine service life and performance Anything less is a compromise and the risk is the user s responsibility Dirty fuels and fuels not meeting Caterpillar s minimum fuel specifications will adversely affect engine performance and will shorten engine life Itis good economics to carefully consider fuel selection LEGV 4801 02 42 L esson Plan 9 02 Small E ngine Fuel Systems L esson Plan 3 Fuel Related Problems Objectives The student will be able to demonstrate the ability to measure fuel API when given a sample in a lab exercise and convert non standard readings to standard with at least 70 accuracy on a written
45. GV 4801 02 292 Slide T ext R eference 9 02 Set Fuel Setting SLIDE 205 Adjust FLS To make an adjustment to the FLS screw put a wrench on the locknut Recheck and loosen it while holding the adjustment screw with a screwdriver Turn the adjustment screw until the desired fuel setting is achieved Hold the adjustment screw with the screwdriver and tighten the locknut Recheck the fuel setting by repeating the procedure LEGV 4801 02 293 Slide T ext R eference 9 02 Torque Group SLIDE 206 FTS After the FLS has been measured and or set write down the dimension that is on the dial indicator Then write down the dimension for your engine Find the difference to determine th number of shims to be removed or installed to bring the FTS Full Torque Setting within specifications Lossen the two bolts holding the shim pack and carefully lift the group out including the insulator block Add or remove shims as required to meet specifications Install the group back on the housing and install the bolts Do no over torque as this could break the insulator block Be sure to assemble the torque spring assembly parts correctly in the same sequence as it was disassembled L E G V 4801 02 294 Slide T ext R eference 9 02 Re Assemble Governor CATERPILLAR SLIDE 207 Recheck settings Repeat the test procedure to make sure the FLS FTS are correct and the dial indicator reading is the same as the dimension given for your engi
46. Gasoline or naptha Safety hazard Evaporation rates 37 Slide T ext R eference Gasoline Addition SLIDE 14 To lower cloud point and pour point temperatures of their fuels some users blend diesel fuel with gasoline or naphtha Because of the safety hazard involved Caterpillar does not recommend that users mix diesel fuel with gasoline or naphtha Safety practices which may have worked well with pure diesel fuel will not be adequate when dealing with these blends In a fuel tank the vapor in the air space above pure diesel fuel is too lean to be a hazard at normal ambient temperatures Pure gasoline vapors are too rich However when diesel fuel is mixed with gasoline or naphtha the vapor to air ratios can be explosive Caterpillar recommends the other methods already discussed to lower pour point or cloud point temperatures L E G V 4801 02 9 02 38 Slide T ext R eference Alcohol Addition CATERPILLAR Alcohol to adjust pour point and cloud point L ow cetane number Poor lubricating characteristics SLIDE 15 Some users also like to use alcohol to adjust pour and or cloud point Alcohol either methanol or ethanol has a low cetane number and poor lubricating characteristics The cetane numbers of ethanol and methanol are similar in a range of 0 to 10 This means that pure alcohol does not have good ignition characteristics when used in a diesel engine and must be mixed with large quantities of cetane im
47. I Injector SLIDE 130 Pry on the injector Pry only on the injector body DO NOT pry on the solenoid or solenoid body adapter Prying on the solenoid or solenoid adapter can cause misalignment between the poppet valve and the injector body An o ring seal is shown at the bottom of the injector This was present on all older injectors The new ones do not have it and it should be removed on the old ones The o ring was there to serve as a temporary seal until carbon began to build up It was removed since its presence reduced clamping force LEGV 4801 02 199 Slide T ext R eference 9 02 Injector Sleeve EEA D y LAR SLIDE 131 Replace injector Once the injector has been removed the injector sleeve can be replaced sleeve if necessary U se the 143 2099 Sleeve Replacement Tool Group to Interference replace the injector sleeve Follow the procedure in the Special Tool Group Instruction for the 143 2099 Sleeve Replacement Tool Group F orm No SEHS9120 The HEUI injector sleeve is 1 0 mm shorter than the ones used on the M UI engines in the past Installation of an earlier M UI injector sleeve will cause interference between the sleeve and the injector and the injector will not seat properly These older sleeves were canceled and replaced by the new ones The 143 2099 Sleeve Replacement Tool Group consists of the 127 3462 Sleeve Replacement Tool Group and the 127 3460 Sleeve Replacement Tool Group LEGV 4801 02 200 Slide
48. Injection pressure is infinitely controlled between maximum and minimum Conventional pressure limits regardless 7 of engine speed i x l ft i x ia i um i k tJ m ENGINE SPEED CATE SLIDE 110 Peak Injection With any system other than HEUI the peak injection pressure is a at any dependant on engine speed The slower the engine speed the less peak p injection pressure is available With HEUI peak pressure can be obtained at about any engine speed even low idle L E G V 4801 02 178 Slide T ext R eference 9 02 HEUI Schematic mHigh Pressure Oil Suction Drain Fuel Pressure Il SLIDE 111 HEUI components Now let s look at the basic components of the HEU system The HEUI fuel system consists of five major components They are an electronic control module ECM and sensors a high pressure oil pump the oil manifold and oil lines the fuel transfer pump and fuel lines the injection actuation pressure control valve IA PCV and the HEUI Injectors The ECM is a programmable on board computer which controls the operation of the entire fuel system as well as other engine functions Because the ECM has many more operational inputs than a mechanical governor it can determine optimum fuel rate injection timing and injection pressure for almost any condition Electronic controls such as this are absolutely essential in meeting new standards of exhaust emissions and noise
49. PILLAR SLIDE 47 Torque rise is the percentage difference between the torque available at rated versis the torque available at peak torque rom The torque of the engine is its true power At peak torque rom we find the most torque with a lowered fuel volume Therefore the operator gets more force for less fuel when the engine is operated at a lower rom L E G V 4801 02 78 Slide T ext R eference 9 02 POWER CURVES BSFC Horsepower BSFC Brake Specific Fuel Consumption is the pounds of fuel it akes to produce one horsepower for one mour RPM Governed Speed 2100 High Idle 2262 CATERPILL AR E SLIDE 48 The efficiency of the engine is recorded by the use of BSFC Brake Specific Fuel Consumption This is the amount of fuel in pound per horsepower hour or grams per kilowatt hour The smaller the number the more efficient the engine The engines are designed to provide the best fuel efficiency at the recommended operating rom This number changes with both rom and power demand The curve shown is a full load BSFC curve L E G V 4801 02 79 Slide T ext R eference 9 02 POWER CURVES Droop Overrun Droop FTS Horsepower Droop Overrun The percent of rpm increase at high idle as compared to that at governed RPM Governed Speed 2100 High Idle 2262 CATERPILLAR MPS ibidis SLIDE 49 Droop or overrun is the percent of rom the engine is allowed to run above governed and compared to governed rom T
50. Quiz 2 Select the best answer If the answer is false on a true fales correct the question to make it true 1 The Type ll governor used on a 3114 engine C A Is the same as the Type governor except it has a Type Code Bon the information plate B Has two governor flyweights and uses a servo to control rack movement C Has four governor flywieghts to control rack movement D Has no torque cam adjustment 2 The3114 engine has a centrifugal timing advance unit built ino the cam gear and has a maximum advance of 6 degrees B MUI can t havea TAU A True B False 3 The fuel setting on 3116 engines can be made with the governor attached to the engine A A True B False 4 When adjusting a 1 1 or 1 2 liter engine governor on the governor test bench the governor output at peak torque is checked by D A Increasing the bench speed by 100 rom and lowering bnack to the adjustment specification speed B Performing function check 2 C The output at peak torque can not be tested on a 1 1 or 1 2 engine governor D Performing function check 3 L E G V 4801 02 156 Test 6 02 When setting the dial indicator on the governor test bench the reference setting dimension for a governor with a load stop dimension less than 9 00 mm is C A 0 00 mm B 9 00 mm C 8 00 mm D The dimension that is found in the Governor Performance data in TM The torque cam adjustment dimension is found B A Testing and
51. Rotate the engine in the direction of engine rotation until the TDC 1 TDC mark on the damper and the pointer are in alignment LEGV 4801 02 269 Slide T ext R eference 9 02 Pin Cam TDC He CATERPILLAR Engin maming veo SLIDE 182 Mark on Damper The timing pin should fall into the slot in the fuel pump camshaft when Pointer the mark on the damper and the pointer are in alignment LEGV 4801 02 270 Slide T ext R eference 9 02 a NAE Tach Drive Cover D poy SLIDE 183 Remove Plug Remove the plug from the timing bolt hole With a 5 16 bolt the one shown loose at the lower right hand corner from the front housing insert it into the hole for the timing bolt lower right side of pulley out of the picture and turn it into the threaded hole in the valve camshaft gear If the timing pin goes into the groove in the slot in the injection pump camshaft and the bolt will turn into the valve camshaft gear the timing of the engine is correct If the bolt will not turn freely into the gear the timing is not correct L E G V 4801 02 271 Slide T ext R eference 9 02 Remove Tach Drive p SLIDE 184 Changing Pump To change the fuel pump timing first remove the tachometer drive Timing adapter e ane This bolt sleeve is the tachometer drive It also holds the drive gear of the injection pump camshaft on the tapered drive flange on the end of the camshaft and fastens them together L E G V 480
52. Script Quiz 3 C 9 Fuel System Slide Script HEU HI300B Fuel System Literature L ist Copy Copy LEX Q9297 Copy Copy SEBD0717 LEX T1044 LEK Q6070 LEK Q6071 Copy Copy Copy Copy Copy Copy Copy SENR 3583 SENR3130 HEHS0610 SENR6454 Copy NEHS0675 Copy Copy Copy RENR1392 LEGV 4801 02 6 9 02 6V 4141 Sleeve Calibration Tool 5P6577 Fuel Setting Tool Group Analyzing Fuel Nozzle and Fuel Line Failures Using the 5P4150 Nozzle Testing Group Test Sequence for Capsule Type Fuel Nozzles Test Sequence for 7000 Series Fuel Nozzles Test Sequence for Pencil Type Fuel Nozzles Final Test Course Evaluation Sheet Literature L ist SMHS 7835 SM HS7013 SEB D0639 SEHS7292 SEHS7350 SEHS9083 SEHS7390 Copy Copy LEGV 4801 02 9 02 Small Engine Fuel Systems Student Literature L ist Registration Form Small Engine Fuel System Schedule Pre Test Engine Performance Reference Sample OT 2T Information from the TM1 SIS or SIS Web Sample Engine Performance Information from the TM on line system Quiz 1 Quiz 2 Quiz 3 Final Test Course Evaluation Sheet Literature L ist Copy Copy Copy LEXT1044 Copy Copy Copy Copy Copy Copy Copy LEGV 4801 02 8 9 02 Small E ngine Fuel Systems H ardware L ist Slide Projector Screen Fuel Selection Slides 1P7408 T hermo hydrometer 5P2712 Thermo hydrometer 1P 7438 Beakers Various fuel samples Basic Governor Slides Power Curv
53. Slide T ext R eference 9 02 Governor Balance SLIDE 26 Spring force equals As long as the spring force equals the flyweight centrifugal force the the centrifugal force engine speed remains constant of the flyweights Constant speed L E G V 4801 02 53 Slide T ext R eference 9 02 Rack Actuation sait SLIDE 27 Speed measuring The speed measuring mechanism senses and measures engine speed mechanism changes The fuel changing mechanism links the speed measuring Fuel changing mechanism with the fuel injection pumps to control fuel and with that mechanism the engine speed Link to fuel injection pump L E G V 4801 02 54 Slide T ext R eference 9 02 Flyweight Force CATERPIL SLIDE 28 Speed increase As the engine speed increases the flyweights will move outward This Simple linkage movement is transferred through a simple linkage to the rack and therefore to the fuel injection pump plunger rotating it to change Injection duration ee decrease Injection duration L E G V 4801 02 9 02 55 Slide T ext R eference Governor Spring Force j CATE E ngine load increases E ngine speed decreases Flyweight force Rack position SLIDE 29 W hen the engine load increases as when a truck starts up a hill the engine speed decreases Due to the slower engine speed the flyweight force decreases and the spring moves the linkage and rack to increase the fuel to the engine The increased
54. ady to begin again The unit injector iS now back in the pre injection cycle L E G V 4801 02 236 Slide T ext R eference 9 02 CATERPILLAR SLIDE 158 Although the 3126B E injector looks different than the 3126 injector the function is very similar The prime differences their function and Operation are the orientation of the poppet valve and the addition pilot injection on the 3126B E L E G V 4801 02 237 Slide T ext R eference 9 02 HEUI Fuel Systems T Use electical currents from the ECA to perharm work or to change engine partormance SLIDE 159 Actuators All of the functions of the fuel system are controlled by the ECM using the infomation it gathers from the various engine sensors This data is used to control engine actuators The first actuator the IA PCV controls injection pressure by controlling the pressure of the HEU I oils supply The second actuator the solenoid on the HEUI injector controls timing and duration LEGV 4801 02 238 L esson Plan 12 01 SMALL ENGINE FUEL SYSTEMS Lesson Plan 16 Quiz 3 Objectives e The student will take a quiz to review and test the previous day s material A minimum of 70 accuracy is considered acceptable Literature Quiz 3 Copy H ardware Needed None Time R equired 0 5 hours Tasks R equired by Instructor to M eet Objectives 1 Ask students for questions regarding material covered the previous day 2 Answer all questions using reference
55. al procedure must be used for setting the dial indicator calibration dimension Refer to the Bench Preparation Procedure Setting the Governor Load Stop Dimension For M ore Than 9 00 mm in the Service M anaul for 3114 3116 amp 3126 Engine Governors Form No SENR6454 L E G V 4801 02 121 Slide T ext R eference 9 02 Aadjusing Screws Older Epas r a i Sec KEK ee CATERPILLAR Engine Training Clb SLIDE 74 Typel through IV The top screw shown here is load stop adjustment screw on type nen through IV governors L oad stop adjustment The bottom screw is the adjustment for the fuel ratio control on type and IV governors screw FRC adjustment screw The low idle and throttle stop adjustment screws are located on top of L ow idle the governor housing T hrottle stop LEGV 4801 02 122 Slide T ext R eference 9 02 Adjusting Screws Newer as EERTE E 7 m 4 i j Sy Ba r ee CATERPILLAR Trmkning Dri SLIDE 75 Type V and VI On type five and six governors the screw shown on the lower left is the aa OTS load stop adjustment The one on the upper right is for the fuel ratio L oad stop adjustment control FRC adjustment The low idle and throttle stop adjustment screws are located on top as L ow idle with the earlier governors T hrottle stop LEGV 4801 02 123 Slide T ext R eference 9 02 Throttle Stop Screws CATERPILLAR SLIDE 76 Throttle stop The throttle
56. ard L E G V 4801 02 264 Slide T ext R eference 9 02 Fuel Priming Pump SLIDE 177 Fuel Priming Pump The fuel priming pump is located on the fuel filter base The priming pump can be used to evacuate any air in the system To do this open the air bleed valve and pump the handle until fuel without air comes out of the drain hose After the air is removed from the fuel pump housing close the bleed valve If the air is down stream from the pump the fuel line nuts at the cylinder head may need to be loosed during operation to bleed air within the lines themselves LEGV 4801 02 265 Slide T ext R eference 9 02 High idle Screw SLIDE 178 Low Idle Adjustment The adjustment screw for low idle is located on the outside left of the High Idle Adjustment governor housing J ust above the lower spring in the picture The high idle screw is located under a cover on the top of the governor housing the unpainted screw and locknut LEGV 4801 02 266 Slide T ext R eference 9 02 Fuel Cam TDC Plug SLIDE 179 Check Timing To check the timing of the fuel pump camshaft remove the bolt shown on the top right side of the governor housing LEGV 4801 02 267 Slide T ext R eference 9 02 Insert Cam TDC Pin ILLAR nz Livi SLIDE 180 Timing Pin Drop the timing pin into the timing pin hole LEGV 4801 02 268 Slide T ext R eference 9 02 Rotate Sagina oe lt SLIDE 181 Rotate the E ngine to
57. are moved the fuel pump calibration will be changed LEGV 4801 02 281 Slide T ext R eference 9 02 P amp B Removal ES SPN be aa i an User ENER CATER Engines Irmaming Livion SLIDE 194 Remove P amp B To remove the fuel injection pumps install the 852243 wrench Turn assemblies the wrench and lossen the bushing of the injection pump Remove the pump and mark its location The sleeve may drop off the plunger when the pump assembly is removed It can be removed from the pump housing with a magnet LEGV 4801 02 282 Slide T ext R eference 9 02 Plunger amp Barrel Assembly wall SLIDE 195 Install P amp B To install the injection pump put the sleeve on the plunger with the thin assembly flange of the sleeve toward the barrel as shown Turn the camshaft of the injection pump so that the lifter is on the lowest place on the cam M ove the governor control to the high idle position These actions will make installation of the pump easier L E G V 4801 02 283 Slide T ext R eference 9 02 P amp B Installation SLIDE 196 P amp B assembly Put the injection pump straight down into the bore If necessary use a straight into bore finger to guide and hold the sleeve as you fit the lever into the groove of the sleeve Tighten the bushing to specifications as listed in the Service M anual L E G V 4801 02 284 Slide T ext R eference 9 02 Pump amp Governor CATERPILLAR ee gine
58. as its own fuel rack controlled by the governor with a rack control linkage which actuates all of the unit injectors simultaneously L E G V 4801 02 97 Slide T ext R eference 9 02 MUI Cut Away sait SLIDE 55 Hold down clamp The large extension on the side of the injector is the hold down clamp Rack Shown on the bottom injector is the rack Its movement controls the pinger rotation of the helix on the scroll of the plunger thus determining the volume of fuel to be injected into the cylinder The unit injector Nozzle consists of ascroll type high pressure plunger and injector nozzle T otal stroke Effective stroke of the plunger during which high pressure fuel is E fective stroke injected is controlled by the scroll position which is actuated by the governor and rack This system is basically like other Caterpillar scroll type fuel systems except the high pressure pumps are separated and individually positioned above each combustion chamber thereby eliminating the need of high pressure fuel lines Total plunger stroke is always the same and determined by the cam lobe lift and rocker arm motion The effective stroke however is determined by the scroll position The plunger rotates about its vertical axis to move the scroll hence lengthening or reducing the effective stroke During the time both ports are covered fuel is injected Fuel pressure forces the check L E G V 4801 02 98 Slide T ext R eference 9 02 off it
59. ature moves toward the solenoid the armature lifts the poppet valve off the poppet valve s lower seat L E G V 4801 02 9 02 227 Slide T ext R eference Energizing the solenoid and lifting the poppet valve off the poppet valve s lower seat is the beginning of the fuel injection process POPPET VALVE The poppet valve has two positions which are opened and closed In the closed position the poppet is held on the lower poppet seat by a spring The closed lower poppet seat prevents high pressure actuation oil from entering the unit injector The open upper poppet seat vents oil in the cavity that is above the intensifier piston to the atmosphere The oil is vented to the atmosphere through the upper portion of the unit injector In the open position the solenoid is energized and the poppet valve is lifted off the poppet valve s lower seat When the poppet valve is lifted off the poppet valve s lower seat the lower poppet seat opens allowing high pressure actuation oil to enter the unit injector When the high pressure actuation oil enters the unit injector the high pressure actuation oil pushes on the top of intensifier piston The upper poppet seat of poppet seat of poppet valve blocks the path to the drain Blocking the path to the drain prevents the leakage of high pressure actuation oil from the unit injector INTENSIFIER PISTON The surface area of intensifier piston is a bit over six times larger than the surface area of plunger
60. before you install it B Never A True B False LEGV 4801 02 90 L esson Plan 9 02 Small E ngine Fuel Systems L esson Plan 8 Fuel Setting Information Objectives e The student will be able to select proper OT 2T OK and Performance Information from the TM I on line system in a lab exercise and with at least 70 accuracy ona written test e The student will be able to select appropriate engines for a task by looking at various performance sheets in a classroom lab exercise Literature Needed Sample OT 2T from TMI SIS or SIS Web Copy Sample Engine Performance Information from TM Copy H ardware Needed On line Terminal Time R equired 1 Hour Tasks R equired by Instructor to M eet O bjectives 1 Explain the method of retrieving OT 2T 0K information using the TM I on line system and or SIS system 2 Find and print a copy of the OT 2T OK information and engine performance information for a 3116 engine with a 250 2600 rating using the TM on line system 3 Review the type and placement of all of the data on the above two documents Discuss any tolerances that may apply to the engine performance information 4 Answer any questions about the OT 2T OK and or the performance information LEGV 4801 02 91 L esson Plan 9 02 Small E ngine Fuel Systems L esson Plan 9 Introduction to 1 1 and 1 2 M UI Fuel Systems Objectives e The student will be able to explain the operation disassembly ass
61. block on the calibration plate so that the longer dimension is vertical Install the dial indicator 6V 6106 into assembled tooling Lift up on knurled portion and carefully lower ball onto the gage block There is a notch on top of the Knurled handle that aligns with the stem and ball Be sure only the ball touches the gage block An incorrect setting will result if the stem touches the gage block Raise or lower the indicator in the fixture until all of the pointers read zero or if using a digitial indicator zero the indicator L E G V 4801 02 111 Slide T ext R eference 9 02 Riser Assembly SLIDE 66 Assemble riser Assemble the riser with shims bearing races Itis not necessary to install the retaining ring while making this adjustment Install the riser on the riser shaft with the bearing races on the flyweights L E G V 4801 02 112 Slide T ext R eference 9 02 setting Riser Position SLIDE 67 Install tooling Install the tooling on the governor front housing Put the weight on top Indicator difference of the riser to compress the shims Lift up on the knurled knob and from zero place ball into the riser slot surface and read the indicator The dial indicator difference from zero equals the thickness of shims to add or remove until the reading is 0 08 mm 0 003 in Once the correct number of shims has been determined remove the riser and install the retaining ring LEGV 4801 02 113 Slide T ext R efe
62. chanism Now Fuel off direction what is centrifugal force If we tie a ball on a string and swing it around and around the faster it goes the more centrifugal force outward force is exerted on the ball This centrifugal force swings the ball outward and upward until the ball is nearly straight out We can see that the faster we swing it the greater the pull on the string and the farther outward it swings Increasing the centrifugal force of the flyweights in the governor will move the rack in the fuel off direction Speed change L E G V 4801 02 50 Slide T ext R eference 9 02 Governor Spring Force SLIDE 24 Governor spring We need to control this centrifugal force so we have the governor Fuel on direction spring The spring acts against the force of the rotating flyweights and tends to oppose them The force exerted by the spring depends on the governor control setting Increasing the force applied to the governor spring will move the rack in the fuel on direction L E G V 4801 02 51 Slide T ext R eference 9 02 Throttle Compressing Governor Spring mwad a SLIDE 25 Governor control A lever connected to the governor control throttle pushes on or lever compresses the spring The spring force opposes the flyweights to regulate the desired engine speed setting The governor control shown here as a simple push pull knob may be a hand operated control or a foot operated accelerator pedal L E G V 4801 02 52
63. compressor on the unit injector to allow free movement of the racks A pply a small amount of clean engine oil to the top of the injectors Install an injector spring compressor on each of the injectors Compress the injector by tightening the bolt Tap lightly with a soft hammer on the spring compressor to ensure free movement of the injector rack bar L E G V 4801 02 9 02 Injector synchronization using the 128 8822 tool group Install the fixture group Install gage block 129 Slide T ext R eference patel amp Tension SLIDE 82 Injector synchronization using the 128 8822 tool group Remove the valve cover and rocker arm assembly for number one cylinder If desired remove the rocker arm assemblies for the injectors to be synchronized Be sure that the rocker arm assemblies are held together if they are removed M ove the number one injector rack to the full fuel off position Install the 128 9640 fixture group on cylinder head at the number one cylinder B e sure that the detent clears the rack bar when tightening the fixture group M ove the number one rack in the fuel on direction and put the 9U 7270 gauge block in position on the number one injector with 3 5 mm wide finger positioned between the injector rack head stop pin and the square shoulder on the injector body Release the rack The gage block is to be secured to the fixture group by the chain L E G V 4801 02 130 Slide T ext R eference 9 02
64. ction pressure and must be monitored by the ECM If the pressure is not what the ECM desires it will change its signal to HEP to change HEU manifold pressure This provides a closed loop system for HEUI oil pressure L E G V 4801 02 254 Slide T ext R eference 9 02 Speed Timing Sensors CAT SLIDE 168 The C 9 has dual speed timing sensors like the 3126 models which work the same way LEGV 4801 02 255 Slide T ext R eference 9 02 Inj ectors Rockers SLIDE 169 H ere we see the valve cover removed showing the rocker assemblies and the HEUI injectors The C 9 injector has a different shape and a modified operation that we will discuss later LEGV 4801 02 256 Slide T ext R eference 9 02 C 9 7 Injector amp CATERPILLAR Engine Timining l ev Gaon SLIDE 170 Here we see the HEU injector nestled between the valves The two wire electrical connector is shown in the unlocked position making it ready to disconnect LEGV 4801 02 257 Slide T ext R eference 9 02 Injector o Hold YE CATER SLIDE 171 The connector has been removed On the top the injector the serial number can be found To the right and left the allen head hold down bolts and hold down clamp are shown LEGV 4801 02 258 Slide T ext R eference 9 02 Injector Puller SLIDE 172 The injector puller is shown installed in the above slide A breaker bar is used as the pulling lever arm Prying the injector up
65. d to use fuel heaters to overcome the effects of cold weather on fuels A A True B False 20 Which of the 1 1 liter governor types use four governor flyweights to control rack movement B A Typel Type 2 B C Type 3 D Type 4 z Type5 LEGV 4801 02 21 L esson Plan 9 02 Small E ngine Fuel Systems L esson Plan 2 Fuel Selection Objectives e The student on a written test will be able to explain the characteristics of diesel fuels with at least 70 accuracy e The student will be able to select proper fuels for Caterpillar engines on a written test with at least 70 accuracy e The student on a written test will be able to explain proper fuel system maintenance procedures for Caterpillar engines with at least 70 accuracy Literature Needed Fuel Selection Slide Script Copy Diesel Fuel and Your Engine SEBD0717 Hardware Needed Projector Screen Fuel Selection Slides Time Required 1 25 Hours Tasks R equired by Instructor to M eet O bjectives 1 Review the slides and emphasize the following points A Preferred fuels B The function of cetane in the fuel C Water and sediment in the fuel D The effect of low temperature on a fuel 1 Cloud point 2 Pour point E Methods of changing cloud pour point of fuel LEGV 4801 02 22 L esson Plan 9 02 2 3 1 Gasoline 2 Alcohol 3 1 Diesel F Sulfur in the fuel Using Diesel Fuels and Y our Engine emphasize the following
66. dary filter Cylinder head Unit injectors Orifice 93 Slide T ext R eference 3116 Fuel System Schematic SLIDE 51 The 1 1 liter engine fuel system employs a mechanical unit injector combining both the nozzle assembly and the high pressure fuel injection pump The fuel transfer pump 1 pulls fuel from the fuel tank through an in line primary filter 2 and sends fuel to a spin on type secondary fuel filter 3 From the fuel filter fuel enters a drilled passage at the rear of the cylinder head The drilled passage carries fuel to a gallery around each unit injector and provides a continuous flow of fuel to all of the unit injectors Unused fuel exits the cylinder head passes through a 1 3 mm 050 in pressure regulating orifice and a check valve 4 and returns to the fuel tank 5 This system is very compact eliminates external high pressure fuel lines Additionally this system allows very high injection pressures and short injection times with subsequent emission control L E G V 4801 02 94 Slide T ext R eference 9 02 Fuel mar he SLIDE 52 Check valves The check valve shown keeps fuel from bleeding out of the fuel gallery Start up after shutdown to ensure a fuel supply for start up This is the same design valve as is used in the transfer pump The pressure regulating orifice ensures adequate fuel pressure and controls the return to tank flow rate Transfer Pump The fuel transfer pump is located in the front
67. de T ext R eference 9 02 Poppet Valve Intensifier Piston End of Injection inlet Fill Check Ball CATERPILLAR SLIDE 157 End of Injection The end of the injection cycle begins when the ECM stops the current to the unit injector solenoid The magnetic field of the solenoid breaks down and the magnetic field is unable to overcome the spring force of the poppet The poppet returns to the lower poppet seat which closes the poppet valve W hen the poppet valve closes high pressure oil is stopped from entering the unit injector As the lower poppet seat closes the upper poppet seat opens to the drain When the upper poppet seat opens to the drain the actuation pressure of the oil drops off Fuel injection pressure under the plunger and the plunger return spring exert an upward force on the plunger and the intensifier piston As the pressure of the actuation oil above the intensifier piston drops off the downward force on the intensifier piston drops off The upward force of the fuel injection pressure under the plunger coupled with the plunger spring force suddenly becomes greater than the downward force on the L E G V 4801 02 9 02 235 Slide T ext R eference intensifier piston The downward motion of the intensifier piston and the plunger stops The exhaust oil on top of the intensifier piston can flow to the drain through the open upper poppet seat Then the oil flows through a vent hole to the rocker arm compartment
68. e lever or a press on type lever Type IV governors can be identified by the type code A or the numbers 0 or 1 following the serial number Type lV governors L E G V 4801 02 9 02 102 Slide T ext R eference will have a press on type throttle lever Type V governors can be identified by the type code D following the serial number and a press on type throttle lever Type V governors also have the fuel ratio control cast into the governor housing Type VI governors will also have type code D following the serial number press on type throttle lever and cast in fuel ratio control housing Type VI governors sometimes referred to as dual horsepower governors will have a dual horsepower mechanism on the side of the governor Type VII governors will also have type code D following the serial number press on type throttle lever and cast in fuel ratio control housing Type VII governors sometimes referred to as dual horsepower governors will have a dual horsepower mechanism on the side of the governor Type VIII governors are used on the Challenger Tractors LEGV 4801 02 103 Slide T ext R eference 9 02 Governor Front P SLIDE 59 Gear driven The governor is gear driven from the engine camshaft This drives the F lyweights flyweights inside the governor The flyweights move the riser on the riser shaft The movement of the riser on the shaft is opposed by a spring pack Engine speed and
69. e Slides Calculator Test Conditions Slide On line Terminal 1 1 Liter Fuel System Slides 1 1 or 1 2 liter M echanical Engine 128 8822 Tool Group Hand Tools 1 1 or 1 2 Mechanical Governor 128 8822 1 1 Liter Engine Injector Tool Group 1U 7315 1 1 Liter Engine Governor Tool Group 1U 7326 Governor Calibration Bench 1U 9786 Calibration Pin 1U 6673 FRC Adjustment Wrench 1U 9893 Solenoid Spanner Wrinch 6V 6106 Dial Indicator 1U 8815 Contact Point Literature L ist LEGV 4801 02 9 Literature L ist 9 02 15 psi Air Supply 143 2099 Sleeve Replacement Tool Group 1 1 and 1 2 HEUI Fuel System Slides C 9 HEUI Fuel System Slides HEU H1I300B CD PC Computer 3208 Fuel System Slides 3208 Engine with Pump and Governor 6V 4141 Sleeve Calibration Tool Group 5P6577 Fuel Setting Tool Group 5P4150 Nozzle Test Group Various Fuel Nozzles LEGV 4801 02 10 L esson Plan 9 02 Small E ngine Fuel Systems L esson Plan 1 Introduction amp Pre test Objectives e The instructor will complete all administrative duties required for class start up e The instructor will explain the course objectives and course schedule to the students and answer any questions concerning them e The instructor will explain course safety procedures e The instructor will provide an introduction of himself classmates and training facility e The student will take a pre test so the instructor can gain knowledge of the experience level of the course
70. e torque screw comes in contact with the solid stop This rack position is Full Torque Setting FTS L E G V 4801 02 66 Slide T ext R eference 9 02 POWER CURVES Set Point FLS Set Point Governed speed Set point The point at which 20 rpm the rack screw is in contact with the torque spring 10 to 45 of the time Governed speed 2100 High Idle 2262 CATERPILLAR SLIDE 36 Set Point Set Point is the rom at which the full load screw is in contact with the torque spring between 10 and 45 percent If we then load the engine down 20 more rpm below set point the full load screw will be first in contact with the torque spring 100 percent which is FLS setting governed Therefore governed is always 20 rom below where we find set point We set governed by use of set point since we can not exactly determine the first point of 100 percent contact L E G V 4801 02 67 Slide T ext R eference 9 02 POWER CURVES Horsepower Curve Horsepower FTS N Horsepower Curve The maximun horsepower developed at a rpm with the maximum fuel rate available that rpm Governed speed 2100 High Idle 2262 CATERPILL SLIDE 37 Horsepower curve This is the normal shape of a horsepower curve Typically the horsepower humps up a bit as the rom lug below governed stronger torque spring with larger FTS typically With some curves the power remains flat for a period and then falls off light torque spring with smaller FTS typ
71. eans of a solenoid operated poppet valve PRE INJECTION With the early models the plunger moves down during the injection stroke it closes off the fill port and pushes fuel out of the plunger cavity Fuel flows past the nozzle check around the poppet valve and out the spill port to drain In later models the fill port was eliminated and fill and spill go through the same port INJECTION W hen the Solenoid is energized it closes the poppet valve and blocks the path to drain The downward travel of the plunger causes pressure to build and immediately open the nozzle Injection continues as long L E G V 4801 02 9 02 170 Slide T ext R eference as the solenoid is energized and the plunger continues its downward stroke END OF INJECTION Injection stops when the solenoid is de energized and the poppet valve opens Fuel now flows around the poppet to drain The rapid drop in pressure allows the nozzle check to close ending injection PLUNGER FILL As the plunger travels upward it uncovers the fill or the fill spill port and draws fuel into the plunger cavity L E G V 4801 02 171 Slide T ext R eference 9 02 EUI Fuel Systems Mechanically Actuated Electronic Unit Injector Can inject fuel at up to 30 000 psi High pressure fuel lines are eliminated CATERPILLAR Dirk SLIDE 104 There are three major advantages to this system First the start and end of injection can be controlled to occur at an
72. ection timing is a standard that permits the setting of all unit injectors to the same vertical position on the camshaft base circle so that the beginning of injection takes place in each combustion chamber a specific number of crankshaft degrees before top center Fuel timing is specified as a dimension in millimeters L E G V 4801 02 140 Slide T ext R eference 9 02 Fuel Timing Dimension ay 4 i ji J ea SLIDE 90 Distance from The dial indicator measures the distance from the top of the injector follower to injector follower to the injector body surface This measurement gives the ay relationship of the scroll on the plunger with the ports in the barrel Injector scroll a Fuel timing can be checked or adjusted during the two crankshaft Adjusting sequence position sequence for valve clearance setting or turning the crankshaft in the direction of normal rotation until the injector is at maximum height and the push rod is at its lowest point the lifter assembly is at its lowest point on the base circle of the cam Check and adjust injectors 3 and 4 on a 4 cylinder engine with number 1 piston on top center compression stroke Check and adjust injectors 1 and 2 on a4 cylinder engine with number 1 piston on top center exhaust stroke Check and adjust injectors 3 5 and 6 on a 6 cylinder engine with number 1 piston on top center compression stroke Check and adjust injectors 1 2 and 4 on a 6 cylinder engine with number
73. een the tank and the rest of Proper maintenance the system for best operation Water which remains in the fuel can be taken out by a water separator in most cases In severe applications a large capacity water separator can be used A water separator is only as good as its maintenance The water must be drained off before the rated water capacity of the unit is reached Once the water holding capacity of the separator is reached all additional water will pass through the separator W ater capacity L E G V 4801 02 33 Slide T ext R eference 9 02 Cetane Number Startability amp Performance CATERPILLAR SLIDE 10 Fuel cetane rating Cetane is a chemical found naturally in fuel The Cetane number the Ignition quality amount of the cetane present in the fuel is a measurement of the a ignition quality of a fuel Engine startability and acceleration under Startability o l load are especially sensitive to the fuel cetane rating A higher cetane Performance rating assures ease of starting in most conditions Fuels must have a W hite smoke minimum cetane number of 35 for precombustion chamber engines and 40 for direct injection engines Fuel with cetane levels lower than minimum can cause hard starting white smoke at start up and poor engine performance 35 for PC engines 40 for DI engines Generally an increase of ten in the cetane number will lower the temperature at which the engine can be started approximately 12 to 15
74. eeve is installed in the inlet manifold Remove sleeve Later engines have a groove in the governor end of the sleeve that may be used to pry the sleeve out of the governor housing LEGV 4801 02 135 Slide T ext R eference 9 02 Insert Pin CATERPI SLIDE 86 Install calibration pin The 128 8822 tool group uses a tapered holding tool It should be assembled to hold the insertion tool against the governor housing To position the governor linkage install the 9U 7271 offset calibration pin into link pin of the governor output shaft When properly installed equal lengths of small diameter on pin will extend from both ends of link pin LEGV 4801 02 136 Slide T ext R eference 9 02 ba a S SrA Insert rolding Tool SLIDE 87 Install holding tool Install the 9U 7265 clamp assembly to retain offset calibration pin Do not overtighten tightly against the governor housing calibration face When inserting the tapered holding tool use just enough force to hold the pin against the governor Heavy force on the tapered holding tool could cause the pin to indent itself in the face of the governor housing This is the fuel setting measurement position LEGV 4801 02 137 Slide T ext R eference 9 02 Setting Procedure J p gt wi wai at aa al Z wa sait SLIDE 88 Instali the digital Install the 1U 8869 digital position indicator into 9U 7282 indicator position indicator fixture group Tighten the nylo
75. embly setting procedure and testing of the 1 1 and 1 2 liter M UI fuel system with 70 accuracy on a written test Literature Needed 1 1 Liter Fuel System Slide Script Copy Systems Operation T amp A 3114 3116 3126 Engines SENR 3583 Torque Specifications SENR3130 H ardware Needed Slide Projector Screen 1 1 Liter Fuel System Slides Time R equired 1 25 Hours Tasks R equired by Instructor to M eet O bjectives 1 Review the slides and emphasize the following points A Fuel flow throughout the engine B Transfer pump and system check valves C Types and operation of shutoff solenoids D Unit injector operation E Types and operation of the governor F Fuel settings and injector adjustments using the 128 8822 Tool Group 2 Using Systems Operation Testing and Adjusting discuss where the following information can be found A Fuel pressure location LEGV 4801 02 92 L esson Plan 9 02 B Timing hole location C Injector synchronization D Fuel Setting E Fuel timing Using the Tool Operation M anual discuss where the following information can be found A Injector synchronization B Fuel Setting C Fuel timing Using the Governor Service M anual discuss where the following information can be found A Governor disassembly and assembly procedures B Governor testing and adjusting procedures L E G V 4801 02 9 02 Fuel flow Fuel tank Primary filter Fuel transfer pump Check valves Secon
76. ension SLIDE 71 Governor spring With the O ring seal removed lightly lubricate the housing bore with preload engine oil and loosely fit the rear cover assembly into place Install tooling Remove the fitting and screen assembly in the housing where engine Addorremoveshims oj is supplied to the governor Install the 950229 contact point into the Refer to TMI 6V 6106 dial indicator Install the dial indicator into the 1U 7308 governor spring shim adjustment tool Use a 1D4556 bolt to install the assembled tooling into housing where fitting and screen assembly were removed M ake sure the dial indicator is on the center of the rear cover Push down on rear cover assembly until it makes contact with the governor housing and then zero the indicator Release the cover and rotate it approximately 1 4 turn as the spring pushes up then read the indicator Refer to TM I for the correct spring preload dimension according to the governor group number Add or subtract shims to achieve the correct spring preload dimension After setting remove tooling and cover assembly Install the O ring seal on the cover assembly Put the cover in position on the governor housing and install L E G V 4801 02 118 Slide T ext R eference 9 02 the bolts Install the engine oil supply screen assembly and fitting L E G V 4801 02 9 02 119 Slide T ext R eference Install on Governor Test Governor adjustments L ow idle No set point measuremen
77. er are LEGV 4801 02 81 L esson Plan 9 02 accounted for 2 Review the affects the above operating conditions have on engine performance 3 Discuss how correction factors are determined and multiplied to obtain a Total Correction Factor 4 Give students several sets of operating conditions and have them calculate the Total Correction Factors and apply them to a given engine rating A Example What is the expected flywheel horsepower of a 3126E rated at 300 2200 if the fuel is 39 API 40 F fuel temperature is 140 F air intake temperature is 90 F and barometric pressure is 30 15 40 6 API 60 F 300 1 025 X 1 055 X 0 987 X 1 002 280 5 B Example What is the expect flywheel horse power of a 3116 rated at 215 2600 if the fuel is 41 API 40 F fuel temperature is 120 F air intake temperature is 95 F and barometric pressure is 30 45 42 7 API 60 F 215 1 034 X 1 035 X 0 990 X 1 000 203 5 Discuss the importance of analyzing each operating condition and the effect it has on horsepower 2 Ask if there are any questions and explain the answers using the reference material L E G V 4801 02 82 Slide T ext R eference 9 02 Manufacturing Test Conditions Rated hp 3 at SAE J1995 Conditions 110 F Inlet Manifold Temperature ATAAC 77 F Inlet Manifold Temperature Non ATAAC 30 5 Hg Air Pressure 35 API Fuel 85 F Fuel Temperature Used by all major OEMs Any deviation
78. er is false on a true false correct the question to make it true 1 The largest single operating expense over the life of an engine is A Purchase price B Repairs C Preventive maintenance D Fuel 2 Specific gravity API of fuel is measured with a A Hygrometer Thermometer B C Hydrometer D Pyrometer E Viscometer 3 Thestandard fuel API for CAT diesel engines Is A 35 API 50 F B 41 API 60 F C 38 API 50 F D 35 API 60 F L E G V 4801 02 85 Test 9 02 4 One gallon of diesel fuel 39 API 60 F weighs A 7 206 Ibs B 7 000 Ibs C 7 076 Ibs D 6 910 Ibs 5 Engine fuel settings should be adjusted to compensate for power loss with lighter fuels A True B False 6 Cetane number indicates the BTU content of a fuel A True B False 7 The pour point of a fuel indicates the temperature at which wax crystals begin to form A True B False 8 High sulfur content in diesel fuel can result in Excessive liner wear High power output High oil consumption B C and D A C andD A B C D Excessive blowby E F G All of the above L E G V 4801 02 86 Test 9 02 9 What is the corrected A PI of a fuel that has a measured value of 43 API at 30 F 10 Always pour clean fuel into a new fuel filter element before you install it A True B False LEGV 4801 02 87 Test 9 02 Small E ngine Fuel Systems Lesson Plan 7 Q
79. erial Be sure the students follow along in their reference material while the question is answered 3 Administer the Quiz 2 4 Review the Quiz 2 again using reference material to answer questions L E G V 4801 02 152 Test 6 02 Small E ngine Fuel Systems Lesson Plan 12 Quiz 2 Select the best answer If the answer is false on a true fales correct the question to make it true 1 The Type ll governor used on a 3114 engine A Is the same as the Type governor except it has a Type Code Bon the information plate B Has two governor flyweights and uses a servo to control rack movement C Has four governor flywieghts to control rack movement D Has no torque cam adjustment 2 The 3114 engine has a centrifugal timing advance unit built ino the cam gear and has a maximum advance of 6 degrees A True B False 3 The fuel setting on 3116 engines can be made with the governor attached to the engine A True B False 4 When adjusting a 1 1 or 1 2 liter engine governor on the governor test bench the governor output at peak torque is checked by A Increasing the bench speed by 100 rom and lowering bnack to the adjustment specification speed B Performing function check 2 C The output at peak torque can not be tested on a 1 1 or 1 2 engine governor D Performing function check 3 L E G V 4801 02 153 Test 6 02 5 When setting the dial indicator on the governor test bench the reference setting d
80. esting of the C 9 HEUI fuel system with 70 accuracy on a written test Literature Needed C 9 HEUI Fuel System Slide Script Copy HEUI HI300B Fuel System RENR1392 H ardware Needed Slide Projector Screen C 9 HEUI Fuel System Slides HEU HI300B CD PC Computer Time R equired 1 75 Hour Tasks R equired by Instructor to M eet Objectives 1 Review the slides and emphasize the following points A Fuel system component placement B Priming pump and filter Ca HEP D Transfer pump 2 Using the HI300B CD explain the operation of the HEU B injector and HEP LEGV 4801 02 246 Slide T ext R eference 9 02 C 9 HEUI Fuel systems CATERPILLAR SLIDE 160 The next topic will be the C 9 HEUI fuel system We will build on what we have already learned and discuss the new features of this system LEGV 4801 02 247 Slide T ext R eference 9 02 SLIDE 161 M ost of the fuel system components are located on the left side of the engine To the rear left side the ECM can be seen with its wiring harness Now let s look at the other components LEGV 4801 02 248 Slide T ext R eference 9 02 Priming Pump Fuel Filter CATERPILLAR SLIDE 162 The fuel priming pump and filter base are located at the right front of the engine L E G V 4801 02 249 9 02 Slide T ext R eference High Efficiency Pump HEP age SLIDE 163 With the introduction of the C 9 engine a new style high pressure oil
81. et value of 62 00 mm This is the dimension of the Timing Gauge Block 9U 7269 A Turn the indicator ON by pushing the ON OFF button B Push the in mm button so the display shows mm A negative sign should be in the display window under REV If the Space is blank push the button so the display shows When this is done plunger movement into the indicator will show on the display as negative movement and plunger movement out of the indicator as positive movement D Push and hold the preset button down until there is a flashing P in the upper right corner of the display and then release E Push and hold the preset button down until the P stops flashing and a flashing indicator bar is seen in the lower left corner of the L E G V 4801 02 9 02 145 Slide T ext R eference display and then release M omentarily pushing the preset button will cause a minus sign to appear or disappear above the flashing indicator U se the preset button to make this position blank F Push and hold the preset button down until flashing indicator begins to flash under the first number position fourth position to the left of the decimal then release M omentarily pushing the preset button will cause the display number in that position to change Use the preset button to make the position show zero G Use the preset button to move the flashing indicator a
82. eve Replacement Tool Group Time R equired 1 75 Hour Tasks R equired by Instructor to M eet O bjectives 1 Using the Special Instruction remove an injector sleeve from the engine 2 Using the Special Instruction reinstall the injector sleeve and follow the proper procedure reaming the sleeve seat for a new Injector installation 3 Repeat the process in the form of a demonstration for the 3126B E sleeve LEGV 4801 02 160 L esson Plan 9 02 Small E ngine Fuel Systems Lesson Plan 15 Introduction to 1 1 and 1 2 HE UI Fuel Systems Objectives e The student will be able to explain the operation disassembly assembly setting procedure and testing of the 1 1 and 1 2 liter HEU fuel system with 70 accuracy on a written test Literature Needed 1 1 and 1 2 HEUI Fuel System Slide Script Copy H ardware Needed Slide Projector Screen 1 1 and 1 2 HEUI Fuel System Slides Time R equired 2 Hours Tasks R equired by Instructor to M eet O bjectives 1 Review the slides and emphasize the following points A Benefits of the HEU fuel system B Five major components of the HEU I fuel system C Fuel flow through the fuel system Oil flow through the engine Oil flow through the high pressure system Location of components Removal and installation of an injector rt O nmo Removal and installation of an injector sleeve Operation of the HEUI injector J Operation of the injection actuation pressure control val
83. f a cam lobe An intensifier piston in the HEUI injector multiplies hydraulic force on the plunger By varying hydraulic input pressure injection pressure can be controlled in a range from 5 000 to 23 000 psi LEGV 4801 02 175 Slide T ext R eference 9 02 HEUI Fuel Systems Hydraulically Actuated Electronic Unit Injector A unit injector is positioned above each cylinder An Electronic Control Module ECM controls fuel rate timing and injection pressure The injector is hydraulically operated CATERPILLAR O Engine Training Divison SLIDE 108 Single injector per The HEUI system has a single injector positioned above each of the cylinder cylinders Each injector is controlled by the ECM for duration fuel rate timing and injection pressure Each injector is electronically ECM controls controlled and hydraulically operated Fuel Rate Timing Injection Pressure H ydraulically O perated LEGV 4801 02 176 Slide T ext R eference 9 02 HEUI Fuel Systems Hydraulically Actuated Electronic Unit Injector High pressure fuel lines are eliminated Can inject at up to 23 500 psi CATERPILLAR SLIDE 109 No High Pressure Fuel HEUI systems eliminate high pressure fuel lines The system can Lines achieve as high as 23 500 psi injection pressure 23 500 psi Injection L E G V 4801 02 177 Slide T ext R eference 9 02 HEUI Fuel Systems Hydraulically Actuated Electronic Unit Injector
84. failure can occur LEGV 4801 02 75 9 02 Slide T ext R eference POWER CURVES Wastegate Boost Curve Wastegate Active Reduced BMEP Wastegate Boost RPM Governed speed 2100 High Idle 2262 CATERPILLAR SLIDE 45 To reduce possible failure rates we use a wastegate valve to funnel some of the exhaust gases around the turbine to limit maximum boost and therefore limit BMEP Plugging or clamping off the wastegate line by the customer would cause revocation of warranty since the engine could operate in a higher than desired BM EP range L E G V 4801 02 76 Slide T ext R eference 9 02 POWER CURVES Horsepower Torque Curve The maximum torque value available at a rpm The maximum torque value is called Peak Torque 1200 RPM Governed Speed 2100 High Idle 2262 CATERPILLAR SLIDE 46 The torque curve is the one that the customer really uses It is the pound feet of twisting force that propels whatever is being turned The torque curve does not follow the fuel rate curve Instead it continues to rise with lower rom and fuel rate This is caused by slower pistons speeds giving the fuel more time to burn and reduced internal paracitic loads within the engine L E G V 4801 02 77 9 02 Slide T ext R eference POWER CURVES Peak Torque Torque Rise FTS Horsepower Torque Rise The percentage increase of torque between rated and peak torque rpm RPM Governed Speed 2100 High idle 2262 CATER
85. ft Adjust valves Install valve cover Next tighten the manifold end of the jumper tube to a torque of 40 5 N em 29 4 Ib ft With the clamping fixture still in position tighten the bolts on the injector end of the jumper tube to a torque of 3 Nem 27 Ib in Tighten the bolts again to a torque of 6 N em 53 Ib in Remove the clamping fixture and install the injector hold down clamp 36 N em 26 Ib ft A djust the valves and install the valve cover LEGV 4801 02 203 Slide T ext R eference 9 02 3126 Injector Parts sait SLIDE 135 Five major The HEUI injector has has five major components components SOLENOID Solenoid The solenoid is avery fast acting electromagnet which when energized a pulls the poppet valve from its seat to the oil drain seat which opens the Intensifier piston and injector to high pressure oil and closes the oil drain Poppet valve plunger Barrel POPPET VALVE Nozzle assembly The poppet valve is held on its seat by a spring In this closed position the high pressure inlet oil is blocked and the intensifier cavity is opened to drain W hen the solenoid is energized the poppet is lifted off its seat The path to drain is closed and the inlet for high pressure oil 1s opened INTENSIFIER PISTON AND PLUNGER W hen the poppet valve opens the inlet port high pressure oil enters the L E G V 4801 02 9 02 204 Slide T ext R eference injector and acts on the top of the intensif
86. ft that produces the work b Horsepower is a calculation that can t even be measured on a dynomometer We must measure either torque or fuel rate and calculate horsepower from that data Explain the relationship between horsepower and torque a Asthe engine slows the piston stays in the effective burn window longer providing more time to convert the BTU energy in the fuel to BTU energy of torque b Also as the engine slows the internal parasitic loads lower The energy used to overcome these now go to the flywheel Calculations Place 1000 2100 governed and 1400 1200 peak torque l 2 3 Horsepower Calucalate at both governed and peak torque Show we have 20 loss in power between governed and peak torque G overned hp tX rpm 5252 400 hp 1000 X 2100 5252 Peak Torque 320 hp 1400 X 1200 5252 Torque Rise Calculate torque rise and show while we have lost 20 power therefore about 20 fuel the actual pulling force torque has risen to 140 TR PT GT GT X 100 40 1400 1000 1000 X 100 Droop Overrun Typical droop percents are as follows a Truck 7 to 10 b Marine Vehicular Industrial 5 to 7 c Generator Set 0 to 3 LEGV 4801 02 61 L esson Plan 9 02 DR HI Gov Gov X 100 7 7 2262 2100 2100 X 100 G Fuel consumption 1 BSFC Brake Specific Fuel Consumption The pounds of fuel required to produce one horsepower for one hour a BS
87. fuel position is held until the engine speed returns to the desired setting and the flyweight force again balances the spring force L E G V 4801 02 9 02 Low Idle High Idle RPM Settings Governor Spring F orce Settings 56 Slide T ext R eference Limit Screws SLIDE 30 Two adjusting screws limit the travel of the governor control lever between the LOW IDLE position and the HIGH IDLE position The low idle stop and high idle stop are simply minimum and maximum engine rpm setting with no load on the engine Althought the result is engine rpm the function of the screws would be minimum and maximum governor spring deflection giving us minimum and maximum governor spring force L E G V 4801 02 9 02 57 Slide T ext R eference Fuel Setting Stops CATERPILLAR High idle Increased load Speed changes Collar Stop bar Full load Never operate a diesel engine without a governor controlling it SLIDE 31 W hen the engine is operating with the governor at high idle 1 and picks up a load the engine speed decreases and the flyweight centrifugal force lessens The governor spring moves the rack to give the engine more fuel and increases power The collar 2 and stop bar 3 limit the distance the spring can move the rack As the collar contacts the stop bar full load position is reached This limits the maximum amount of fuel delivered to the engine so as not to exceed design limitations In conclusion it
88. g type 4 An engine has a torque of 505 pound feet at 2600 rom What horsepower is it developing LEGV 4801 02 308 Test 9 02 5 Which of the following can cause excessive black smoke High idle set too low High fuel setting A B C Injector timing dimension 0 5 mm high D A and B E B and C F All the above 6 The best way to lower cloud point of a diesel fuel Is A Add alcohol B Add gasoline C Add 1 diesel D Add cetane E All the above 7 Fuel dilution in a 1 1 liter engine can be caused by A A cut injector o ring B A loose bleed screw in 7000 series nozzle C A broken transfer pump valve D All the above 8 One gallon of diesel fuel 37 API 60 degrees F weighs A 7 206 Ibs B 7 001 Ibs C 6 993 Ibs D 6 910 Ibs L E G V 4801 02 309 Test 9 02 9 Engine fuel settings should be adjusted to compensate for power loss with lighter fuels A True B False 10 Always pour clean fuel into a new fuel filter element before you install it A True B False 11 The most accurate fuel setting information can be found A The OT 2T 0K fiche The Technical Information File B C On the Engine Information Plate D In the Service M anual E In the Testing and Adjusting M anual 12 The purpose s of the governor is to A Prevent engine overspeeding B Keep the engine at the desired speed C Increase decrease engine power output to meet load changes D All the above 13 The ce
89. governor spring and flyweight forces are balanced and the F lyweights engine speed is constant the valve will stop moving Pressure oil will continue to push the piston to the left until the path to drain is opened Oil will now flow along the valve to drain With no oil pressure on the Oil path piston the piston and clevis stop moving Balanced LEGV 4801 02 109 Slide T ext R eference 9 02 Servo Linkage CATE SLIDE 64 Typell governors As mentioned earlier type II governors do not use a servo to control No servo rack movement Instead the type II governors used four flyweights to control the rack movement The use of four flyweights eliminated the Four flyweights Aii need for a servo assist when used on a 3114 engine L E G V 4801 02 9 02 110 Slide T ext R eference Zeroing Riser Position sait Assembly adjustments Riser spool shimming Zero indicator SLIDE 65 During assembly of the governor there are several internal adjustments that must be made in order for the governor to perform properly when running on the calibration bench The first of these adjustments is riser spool shimming This procedure positions the riser spool in the proper location when the flyweights are completely compressed Before shimming the riser spool the indicator must first be zeroed using a gage block Assemble the shim adjustment tool 1U 7309 calibration plate 1U 7312 and gage block 1U 7313 Position the gage
90. he purpose s of the governor is to D A Prevent engine overspeeding B Keep the engine at the desired speed C Increase decrease engine power output to meet load changes D All the above 13 The centrifugal force of the governor flyweights is opposed by the B A Rack B Governor spring C Thottle D Decelerator L E G V 4801 02 316 Test 9 02 14 15 16 17 18 The tolerance on the fuel setting measurements when adjusting the setting is A A 0 00 mm B 0 10 mm C 0 25 mm D 0 50 mm E Noneof the above BSFC Brake Specific Fuel Consumption is C A Amount of fuel to produce rated horsepower for one hour B Pounds of fuel per horsepower minute C Pounds of fuel per horsepower hour D Gallons of fuel per horsepower hour The hydraulic oil pump on a 3126B HEU engine is a seven piston variable displacement axial piston pump B Fixed displacement A True B False On a 7000 series nozzle the bleed screw is in the nozzle during the V OP test B is removed A True B False W hen setting injector synchronization on a 1 1 liter engine the dial indicator is zeroed while the 1 rack is held at shut off B rack of the cylinder being synchornized is held at shut off A True B False LEGV 4801 02 317 Test 9 02 19 20 21 22 23 24 W hich of the following fuels will produce the most horsepower B A JP4 B 39API 120 degrees F C
91. his droop area allows the power to taper off at a rate that is compatable with the type of engine operation No droop is desirable for Generators They need the same rpm regardless of power demand Some engine governors have slight droop that can not be adjusted out 0 3 droop is normal for this application M arine Industrial and machines normally have 5 7 droop while trucks have 7 10 droop LEGV 4801 02 80 L esson Plan 9 02 Small E ngine Fuel Systems L esson Plan 6 Performance C orrection Factors Objectives e Thestudent will be able to calculate expected horsepower loss or gain due to fuel API with at least 70 accuracy on a written test e The student will be able to explain operation of a fuel sight glass with at least 70 accuracy on a written test Literature Needed Test Condition Slide Script Copy Engine Performance Reference LEXT1044 Fuel and Your Engine SEBD0717 Hardware Needed Slide Projector Screen Test Conditions Slide Chalk and Chalkboard Time Required 1 25 Hours Tasks R equired by Instructor to M eet O bjectives 1 Review Standard Caterpillar Test Conditions A Fuel API 35 API 60 F B Fuel Temperature 85 F at the outlet of the fuel filter base C Air Temperature 1 JWAC T and NA 77 F after the air filter and before the turbocharger if it has one 2 ATAAC 110 F in the intake manifold D Barometric Pressure 29 61 or 30 5 if relative humidity and air clean
92. ically With some curves the power falls off immediately when the engine goes below governed no torque spring With each of these curve shapes something within the governor is different L E G V 4801 02 68 Slide T ext R eference 9 02 POWER CURVES Fuel Rate Curve Fuel Rate Horse Power Fuel Rate Curve The maximum fuel rate at a rpm from which the horseyower is developed RPM Governed speed 2100 High Idle 2262 CATERPILLAR p SLIDE 38 Fuel rate curve Here we see a typical fuel rate curve It has a similar shape to the horsepower curve because the horsepower curve comes from the fuel rate curve We get peak horsepower at the point that FTS is achieved This is the largest injection volume and the most injections at this volume per hour As the engine lugs below FTS point we keep the same Injection volume but inject fewer times per hour Therefore fuel rate goes down and due to that horsepower goes down L E G V 4801 02 69 Slide T ext R eference 9 02 POWER CURVES Raise High Idle Horsepower RPM Governed speed 2100 High Idle 2262 CATERPILLAR SLIDE 39 W hen high idle is raised the rom at which we achieve FLS goes up Since FLS rpm is higher set point is higher The reason for this is spring rate does not change so the intersection point of FLS and the droop curve is at a higher rpm Since we get FLS at a higher rpm fuel rate at the new governed speed is higher because we get the sa
93. ier piston Pressure builds on the intensifier pushing it and the plunger down The intensifier piston iS approximatelty 7 times larger in surface area than the plunger providing a multiplication of force The downward movement of the plunger pressurizes the fuel in the plunger cavity causing the nozzle to open A large O ring around the intensifier separates the oil above the piston from the fuel below it BARREL The barrel contains a cross drilled hole with a spring loaded check ball This is called the Barrel Ball Check or BBC It s purpose is to vent any fuel which leaks between the plunger and barrel into the intensifier piston cavity If this cavity were allowed to fill with fuel the plunger would be very sluggish during injection and fuel delivery would be greatly reduced The downward stroke of the piston during injection creates a positive pressure which unseats the spring loaded ball and exhausts any leakage The spring reseats the ball to prevent pressurized fuel on the outside from leaking in NOZZLE ASSEMBLY The nozzle assembly is of conventional design with the exception of the inlet fill check ball and reverse flow check plate The inlet fill check ball unseats during upward travel of the plunger to allow the plunger cavity to refill It seats and seals during the downward stroke of the plunger to prevent injection pressure from leaking out to the fuel supply The reverse flow check is a one way check plate which allows fue
94. igtail 3208 b Internal thread 3400 c External thread 3300 2 All DI 3 Failure modes 1 2 3 Thread adapter damage Bleed screw damage Tip damage blown tip E Fuel Lines 1 Different materials for differnent injection pressures 2 All lines on an engine must be the same length to balance cylinder timing 3 Failure modes a D C Excessive nut torque Tip damage Cracked washer Line breakage 1 Cross beakage vibration 2 Longitudinal crack a Pressure b M aterial defect LEGV 4801 02 305 L esson Plan 12 01 SMALL ENGINE FUEL SYSTEMS L esson Plan 21 Nozzle Test L ab Objectives e The student will be able to properly test PC and DI capsule nozzles using the 5P4150 Nozzle Testing Group in a lab exercise e The student will be able to properly test 7000 series and Pencil type nozzles using the 5P4150 Nozzle Testing Group in a lab exercise Literature Needed Using the 5P4150 Nozzle Testing Group SEHS7292 Test Sequence for Capsule Type Fuel Nozzles SEHS7350 Test Sequence for 7000 Series Fuel Nozzles SEHS9083 Test Sequence for Pencil Type Fuel Nozzles SEHS7390 H ardware Needed 5P4150 Nozzle Test Group Various Fuel Nozzles Time R equired 1 5 Hour Tasks R equired by Instructor to M eet O bjectives 1 Using the 5P4150 manual explain the following 1 Test tooling 2 Test set up procedure 3 Test methods 2 Using the various test sequence sheets have the students run
95. imension for a governor with a load stop dimension less than 9 00 mm is A 0 00 mm B 9 00 mm C 8 00 mm D The dimension that is found in the Governor Performance data in TM 6 The torque cam adjustment dimension is found A Testing and Adjusting B Governor Performance Data C Disassembly and Assembly D Engine Information Plate 7 Theset point for a 3116 truck engine is 20 rom above rated speed A True B False 8 A 3116 engine shows a timing dimension of 63 56 on the engine plate When using the 128 8822 Injector Tool Group the setting on the dial indicator when on the fixture would be A 62 00 mm B 1 56 mm C 63 56 mm D 1 56 mm 9 The throttle stop on a 1 1 liter governor works exactly like a high idle screw on other engines A True B False LEGV 4801 02 154 Test 6 02 10 The throttle lever orientation should be checked on Type 1 2 and 3 governors before making any other governor adjustments A True B False 11 If an engine was producing 597 pound feet of torque at 2200 rpm how much horsepower would it be producing 12 How much horsepower would you expect from a 210 hp 2200 3126E truck engine if it was using 39 API 55 degrees F fuel 67 degrees F fuel temperature 101 degrees air temperature and 28 56 H g barometric pressure Would this custormer probably complain of a power problem Why L E G V 4801 02 155 Test 6 02 Small E ngine Fuel Systems Lesson Plan 12
96. instead of using the tool could cause damage to the injector LEGV 4801 02 259 L esson Plan 12 01 SMALL ENGINE FUEL SYSTEMS L esson Plan 18 3208 Fuel System Introduction Objectives With at least 70 accuracy on a written test the student will be able to identify and explain the function of the individual parts of the 3208 fuel pump and governor Literature Needed 6V 4141 Sleeve Calibration Tool SM HS7835 5P6577 Fuel Setting Tool Group SM HS7013 Hardware Needed Slide Projector Screen 3208 Fuel System Slides Time Required 1 Hour Tasks R equired by Instructor to M eet O bjectives 1 Review the slides and emphasize the following points A Fuel system consists and fuel flow path B Timing procedure C Fuel pressure check D Setpoint check E Pump disassembly F Fuel pump settings G Governor operation 2 Ask if there are any questions and review any areas that might be unclear LEGV 4801 02 260 Slide T ext R eference 9 02 3208 Sleeve Metering Fuel System a SLIDE 173 3208 Sleeve Metering The following presentation will discuss the Sleeve M etering fuel system Fuel System used on the 3208 engine L E G V 4801 02 261 Slide T ext R eference 9 02 3208 Fuel System Schematic pO E Beatan Pir ee SLIDE 174 Fuel Flow This is a schematic of the 3208 fuel system The 3208 engine has a 7000 Series Nozzle sleeve metering type fuel injection pump The engine could have either Caterpi
97. iser to rotate the riser lever and the pivot shaft to a new position Since the torque cam is fixed to the pivot shaft different torque characteristics can be achieved by changing the profile on the torque cam L E G V 4801 02 106 Slide T ext R eference 9 02 Full Fuel Position SLIDE 61 Servo M ovement of the governor output shaft is controlled by the servo on Governor types governor types 1 3 4 5 6 7 and 8 Servo W hen the governor moves in the fuel on direction the valve moves to the left The valve closes the path for pressure oil to go to drain At the same time the valve opens a path to drain to allow the oil behind the piston to escape Pressure oil pushes the piston and clevis to the left Fuel on direction L E G V 4801 02 107 Slide T ext R eference 9 02 Reducing Rack CATERPILLAR SLIDE 62 Fuel off W hen the governor moves in the fuel off direction the valve moves to Valve movement the right The valve closes the path to drain and opens a path for oil to flow behind the piston Pressure oil is now on both sides of the piston The surface area is greater on the left side of the piston than on the right Piston movement side The force of the oil pressure will also be greater on the left side of the piston and moves the piston and clevis to the right Surface area L E G V 4801 02 108 Slide T ext Reference 9 02 Balanced Position CATERPILLAR SLIDE 63 Governor spring W hen the
98. itten test Literature Needed Basic Governor Theory Slide Script Copy H ardware Needed Slide Projector Screen Basic Governor Slides Time Required 0 25 Hours Tasks R equired by Instructor to M eet O bjectives 1 Review the slides and emphasize the following points A Speed measuring mechanism B Fuel changing mechanism C High and low idle screws D Rack limiting devices 2 Emphasize the importance of always having a governor in control when operating an engine L E G V 4801 02 45 Slide T ext R eference 9 02 Mechanical CATERPILLAR SLIDE 19 Mechanical governors This presentation introduces and explains basic operation of the mechanical governor The mechanical governor is the simplest of the various types of governors and is basic to their operation Besides the mechanical governor Caterpillar engines use servo mechanical governors hydraulic governors and electronic governors L E G V 4801 02 46 Slide T ext R eference 9 02 NEVER Ogeta A Diesel Engine Without A Governor Controlline It CATERPILLAR SLIDE 20 Never operatea diesel Never operate a diesel engine without a governor controlling it If you engine without a were to move the fuel rack of a diesel engine to the full ON position i commend without a load with the governor not connected the engine speed might climb and exceed safe operating limits before you could shut it down One second two seconds before you K
99. ixture Continue rotating clockwise winding up the torsion spring Holding the wrench in this position move the dial indicator in the fixture until all of the pointers read zero Tighten the set screw to hold the dial indicator in this position Use the wrench as a lever and rotate the assembly counter clockwise until the torque cam and torque cam setscrew break apart Release the wrench slowly until the setscrew again makes contact with the Torque Cam Release the wrench The reading on the dial indicator will show the torque cam dimension Refer to TM I for the correct dimension If necessary adjust TMI LEGV 4801 02 115 Slide T ext R eference 9 02 the setscrew until correct dimension is shown on the dial indicator L E G V 4801 02 116 Slide T ext Reference 9 02 Governor Spring Preload CATERPILLAR SLIDE 70 Governor spring The governor spring preload must be checked on all governor types to preload insure proper governor operation Shims can be added or removed from the governor spring to adjust the governor spring preload After inspection assemble spring seat assembly and springs onto riser shaft with springs facing up Install governor shims if equipped rear spring seat if applicable shims and spacer If governor is equipped with dashpot piston assembly be sure the dashpot piston assembly is piloted in the rear spring seat L E G V 4801 02 117 Slide T ext R eference 9 02 Adjust Governor Spring T
100. ize the following points A Pass various fuel samples around the room Have the students find the measured API and temperature of each sample Write these findings on the board B Using the fuel API correction chart have the students find the corrected fuel A PI at 60 degrees F Add these finding to the data on the board C Using fuel density correction factors assess how each of the samples would affect performance 1 Find the correction factor for each of the samples and add this to the information on the board 2 Find the corrected power for each of the samples for a 3126E 300 hp 2200 rom a To fine the corrected hp divide the advertised power by the correction factor b The operator would feel it only if we find a hp change of greater than 15 hp 3 Using Blending Used Crankcase Oil with Diesel Fuel LEK Q6070 and Blending Used Crankcase Oil with Diesel Fuel for use with Caterpillar Heavy Duty Diesel Engines LEK Q6071 emphasize that blending used oil with diesel fuel is permissible in some applications but will affect emissions LEGV 4801 02 44 L esson Plan 9 02 SMALL ENGINE FUEL SYSTEMS L esson Plan 4 Basic Governor Theory Objectives e The student will be able to explain the function of the major components of a governor with at least 70 accuracy on a written test e The student will be able to explain the relationship between the flyweights and governor spring with at least 70 accuracy on a wr
101. jumper tube If the tuned fitting is removed from the manifold a new o ring seal should be installed on the fitting J umper tube seat LEGV 4801 02 190 Slide T ext R eference 9 02 Loosen Jumper Fitting SLIDE 122 Remove HEUI To remove the HEUI injector first remove the valve cover Use the Injector 5P0144 Crow s foot wrench to loosen the flare nut that holds the jumper Flare nut tube to the oil manifold The 5P0144 is part of the 125 2580 HEU service tool group LEGV 4801 02 191 Slide T ext R eference 9 02 Remove Injector Clamp PATERPILLAR D Engin Timing Livin SLIDE 123 Hold down bolt Remove the injector hold down bolt and clamp Clamp LEGV 4801 02 192 Slide T ext R eference 9 02 Remove Jumper Screws CATERPI SLIDE 124 Remove jumper tube Use the 125 2584 ball head allen wrench to loosen the injector side flange bolts Disconnect the jumper tube from the oil manifold and the injector and remove the jumper tube from the engine LEGV 4801 02 193 Slide T ext R eference 9 02 Remove Orifice CATERPILLAR Goh SLIDE 125 Removing flange seat Use caution when removing the jumper tube The flange seat that sits on top of the injector may move out of position and fall into the engine The flange seat shown is the original design On later models a metal flange was added Remove the flange seat from the top of the injector L E G V 4801 02 194 Slide T ext R efere
102. l port is a small hole with a high precision tolerance The PRIME spill port is machined through the side of barrel into plunger This port momentarily vents fuel injection pressure during the downward stroke of the plunger NOZZLE ASSEMBLY The nozzle assembly is similar to all other unit injector s nozzle assemblies Fuel that has been pressurized to the injection pressure flows from the plunger cavity through a passage in the nozzle to the nozzle tip Fuel flow out of the tip is stopped by check which covers the tip orifice holes in the end of the tip The force of a spring holds the check down in the closed position This prevents the leakage of fuel out of combustion gas into the unit injector when the cylinder fires L E G V 4801 02 229 Slide T ext R eference 9 02 Injection Stages Pre Injection Pilot Injection Delay Main Injection End of Injection RPILLAR SLIDE 152 There are five stages of injection with the HEUI Pre Injection Pilot Injection Delay Main Injection End of Injection L E G V 4801 02 230 Slide T ext R eference Solenoid HEU Poppet Valve 9 02 Intensifier Piston Pre Injection Plunger Cavity Nozzle CATERPILLAR SLIDE 153 During pre injection all internal components have returned to their spring loaded non actuated position The solenoid is not energized and the and the lower poppet seat is closed When the lower poppet seat is closed the lo
103. l to enter the nozzle assembly but closes to prevent reverse flow at the end of injection It traps fuel pressure in the nozzle to prevent combustion gas from entering the nozzle if the there is leakage between the nozzle tip and check Without the reverse flow check a severe tip leak could allow combustion gas to accumulate in the nozzle At low fuel delivery conditions such as idle this combustion gas would compress and the nozzle would not reach Valve Opening Pressure VOP The injector would not deliver fuel and would become a dead cylinder LEGV 4801 02 205 Slide T ext R eference 9 02 CATERPILLAR SLIDE 136 Four stages There are four stages of injection with the HEUI Prenjecuon Pre Injection Initial injection m or Initial Injection M ain injection ee M ain Injection Return ee Return Cycle Pre injection stage During pre injection all internal components have returned to their spring loaded non actuated position The solenoid is not energized and the poppet valve is blocking high pressure oil from entering the injector The plunger and intensifier are at the top of their bore and the plunger cavity is full of fuel Fuel pressure in the plunger cavity is the Same as transfer pump pressure approximately 60 psi L E G V 4801 02 9 02 206 Slide T ext R eference CATERPILLAR Initial injection SLIDE 137 When the ECM determines that the injector should be fired it sends the correct electric current
104. lay gives the pilot injection the time that is required to start burning The main injection follows the pilot injection and the main injection is delivered into the flame front that was established by the pilot injection The main injection is immediately ignited The main injection burns smoothly and completely This complete combustion significantly reduces particulate emission soot and NO This complete combustion also reduces combustion noise from the engine up to 50 percent therefore noticeably quieter engine Operation L E G V 4801 02 9 02 E gS I aa F 233 Slide T ext Reference Solenoid Poppet Valve Intensifier Piston Main Injection Teese Plunger PRIME Spill Port CATERPILLAR M ain Injection W hile the solenoid is energized the poppet valve remains open While the poppet valve is open high pressure oil flows into the area above the intensifier piston The flow of the high pressure oil pushes downward on the intensifier piston and the plunger The injection pressure fluctuates between 34 M Pa 5000 psi and 162 M Pa 23500 psi The injection pressure depends on the engine s requirements Injection continues until either the solenoid is de energized or the intensifier piston hits the bottom of its bore When the solenoid is de energized the poppet spring is allowed to close the poppet valve When the poppet valve closes the high pressure oil supply is shut off L E G V 4801 02 234 Sli
105. leeve above the upper seat The poppet sleeve is located in the adapter Correct poppet alignment is achieved by precise location of the adapter The adapter is clamped to the body by four screws located underneath the solenoid The screw holes in the adapter have enough clearance to allow the adapter to be moved to achieve correct alignment This alignment can only be done by a robotic assembly machine and cannot be done by hand If the alignment of the adapter is not correct the upper poppet seat will not seal and the injector will have a massive upper seat leak The adapter is not doweled to the body Itis held in position only by the axial force of the adapter screws which clamp it to the body If the adapter screws are loosened or removed the alignment is lost and the injector is scrap It cannot be aligned manually in the field If reinstalled in the engine with an upper seat leak the injector will not fire and will fail the upper seat leak test on the bench test when it is returned for analysis M assive upper seat leak on the test is a sure indication that the injector was disassembled or that the adapter was pried on and moved during injector removal INJECTOR REMOVAL FROM THE CYLINDER HEAD A dapter alignment can also be lost by prying on the adapter during injector removal The injector can be removed by twisting and pulling up by hand or prying up under the the injector body Prying up on the adapter will cause adapter movement and
106. llar 7000 series nozzles or pencil type nozzles Earlier 3208 industrial engines had nozzles with a fuel return line The components of the fuel system are Fuel Tank Tanks Pencil Nozzle Fuel J unction Block Fuel Filter Base and Fuel Filter Priming Pump Fuel Injection Pump and Governor Fuel Lines Bulkhead A dapter Fuel Nozzles L E G V 4801 02 9 02 262 Slide T ext R eference nt aise amp Governor Fuel Injection Pump Transfer Pump Governor C ontrol L ever Fuel Shutoff Solenoid Air Bleed Valve SLIDE 175 The fuel injection pump and governor are located in the forward section of the V of the engine The gear type fuel transfer pump is attached to the front of the pump housing The governor is attached to the rear of the fuel pump housing The governor control lever throttle is located on the left side of the governor housing The fuel shutoff solenoid is on top of the fuel pump This pump has an air bleed valve located at the front right coner of the fuel pump LEGV 4801 02 263 Slide T ext R eference 9 02 Air Bleed Valve SLIDE 176 Air Bleed Valve The air bleed valve is used to remove air from a new filter or if necessary to remove air from the system up to the injection pump housing CAUTION Note that the fuel which escapes from the valve will drain from a hose on the outside of the engine Care should be taken so this f uel does not fall to the ground becoming an enviromental haz
107. loss of poppet alignment Prying on the solenoid will cause it to break L E G V 4801 02 213 Slide T ext R eference 9 02 HEUI Fuel Systems Injection Actuation Pressure Control Valve Pte SLIDE 141 If we must control injection pressure with high pressure oil then we must have a way to control the HEUI oil supply pressure This is done by use of an IA PCV Injection Actuation Pressure Control Valve mounted on the HEUI oil pump L E G V 4801 02 9 02 Injection actuation pressure control valve Fixed pump displacement E ngine off 214 Slide T ext R eference Injection Actuation Pressure Control Valve UAPCY D EA SLIDE 142 The IAPCV is located on the inboard side of the hydraulic pump between the pump and the engine block on the 3126 3116 and on the outboard side on the 3126B E ThelAPCV is an electrically controlled pilot operated pressure control valve This valve is required for two reasons First the pump is a fixed displacement style pump As engine rom increases pump flow increases There are many conditions where pump flow is much greater than what is required by the injectors This excess flow must be dumped to drain with precision and very fast response time Second a variable displacement pump would eliminate excess pump flow but could not react to pressure and speed changes fast enough This would result in pressure overshoot and undershoot during rapidly changing pressure demands
108. ltage from the ECM to the IACPV determines pump output pressure Pump pressure can be maintained anywhere between 725 psi and 3335 psi during normal engine operation Pressure while cranking a cold engine below 30 degrees may be higher than the normal 725 psi The reason for this higher pressure during cold cranking is because cold oil is thicker and components in the injector move slower The higher pressure helps the injector to fire faster until the viscosity of the oil is reduced Due to the oil shearing action of internal engine components such as rings and bearings oil viscosity will drop by over 50 in the first two minutes after start up The injector uses the hydraulic energy of the high pressure oil to cause injection The pressure of the incoming oil controls the speed of the intensifier piston and plunger movement and therefore the rate of injection and injection pressure The amount of fuel injected is determined by the duration of the pulse from the ECM and how long it keeps the solenoid energized As long as the solenoid is energized and the poppet valve is off its seat oil continues to push down the intensifier and plunger until the intensifier hits the bottom of its bore L E G V 4801 02 9 02 L eft side of engine ECM Hydraulic oil pump IAPCV Fuel transfer pump Oil manifold Fuel flow 180 Slide T ext R eference 3126 Left Side SLIDE 112 Lets look at the left side of the engine to see where these comp
109. material Be sure the student follow along in their reference material while the question is answered 3 Administer Quiz 3 4 Review Quiz 3 again using reference material to answer questions L E G V 4801 02 239 Test 9 02 SMALL ENGINE FUEL SYSTEMS L esson Plan 16 Quiz 3 Select the best answer If the answer is false on a true false question corredt the question to make it true 1 The available operating pressure range for the hydraulic oil pressure in a 3116 HEUI engine is A 625 to3335 psi B 725 to 3000 psi C 725 to 3335 psi D 600 to 3335 psi 2 Thefuel ratio control on a Type ll 3116 governor is not in a restrictive position during cranking A True B False 3 A 3126B HEUI engine will not start until the injection actuation pressure has reached A 735 psi B 780 psi C 870 psi D 3000 psi 4 The horsepower tolerance of a new engine at governed speed is A 5 B 3 5 C 6 7 D 3 L E G V 4801 02 240 Test 9 02 5 The difference between governed rpm and high idle rpm is called A Governor overrun B Droop C A andB D None of the above 6 BSFC Brake Specific Fuel Consumption is the amount of fuel consumed to produce one horsepower for one minute A True B False 7 Which of the following is true concerning a 3126B E truck engine A The injector uses a jumper tube B Theinjector has pilot injection C The injector has up to 30 000 psi injec
110. me injection volume more times per hour The same is true of FTS setting and fuel rate The new fuel rate and horsepower curves are as shown with the yellow curve L E G V 4801 02 70 Slide T ext R eference 9 02 POWER CURVES Lower High Idle Horsepower Governed speed 2100 High Idle 2262 CATERPILLAR TE SLIDE 40 W hen high idle is lowered the rom at which we achieve FLS goes down Since FLS rpm is lower set point is lower The reason for this is spring rate does not change so the intersection point of FLS and the droop curve is at a lower rpm Since we get FLS at a lower rpm fuel rate at the new governed speed is lower because we get the same injection volume less times per hour The same is true of FTS setting and fuel rate The new fuel rate and horsepower curves are as shown with the yellow curve L E G V 4801 02 71 Slide T ext R eference 9 02 POWER CURVES Raise Rack RPM Governed speed 2100 High Idle 2262 SLIDE 41 As FLS is raised the engine must be at a lower rpm to find the intersection of the droop curve and FLS This would lower the rated rom therefore lowering set point rom GO Mh CATERPILL L E G V 4801 02 72 Slide T ext R eference 9 02 POWER CURVES Lower Rack RPM Governed speed 2100 High Idle 2262 SLIDE 42 ASFLS is lowed the engine must be at a higher rom to find the intersection of the droop curve and FLS This would raise the rated rom therefore raisi
111. must always be remembered that a governor is capable of reacting faster than we can so never operate a diesel engine without a governor controlling it LEGV 4801 02 58 L esson Plan 9 02 Small E ngine Fuel Systems L esson Plan 5 Performance C urves Objectives e The student with at least 70 accuracy on a written test will be able to explain high idle full load governed set point governor overrun overspeed lug horsepower rack position torque torque rise fuel consumption and boost e The student will be able to calculate horsepower torque torque rise fuel consumption and percent overrun with at least 70 accuracy on a written test Literature Needed Power Curve Slide Script Copy Engine Performance Reference LEXT1044 H ardware Needed Power Curve Slides Projector Screen Chalk and Chalkboard Calculator Time Required 2 Hours Tasks R equired by Instructor to M eet Objectives 1 Using atent curve on the chalkboard or the slides discuss the following subjects A High Idle place 2262 as measured high idle State that 2321 was the high idle found on the engine data plate 1 High idle shown on the data plate is a bare engine high idle This has a tolerance of 40 80 rom to achieve proper set point 2 High idle is not a setting spec It is used to adjust set point when the rack setting is correct 3 High idle on an electronic engine is rated plus 20 rpm L E G V 4801 02 9 02 F
112. n screw Remove the bolt from inlet Zero the indicator manifold near the number one injector and install the indicator fixture Check and adjust fuel group Be sure the ball on end of lever makes contact with end face of setting rack bar Turn the indicator to ON Besure the Indicator units are set to mm and travel direction is correct plunger traveling out of indicator should read positive Push rack head of the number 1 injector by hand toward the injector until rack head stop pin touches square shoulder of injector body and hold in this position The number 1 injector is now at fuel shut off Press the zero set button on the indicator to define zero rack at this position R epeat this process several times to ensure a consistent zero point has been established Push down on the control lever and quickly release it Flip the lever in this manner to make sure there is smooth movement L E G V 4801 02 9 02 138 Slide T ext R eference of the injector rack The reading on the dial indicator is the engine s current fuel setting If an adjustment is necessary use the 1U 6673 wrench to loosen the locknut of fuel setting screw and adjust the indicator reading to the correct fuel setting Turn the screw counterclockwise to increase the fuel setting or clockwise to decrease the fuel setting LEGV 4801 02 139 Slide T ext R eference 9 02 Fuel Timing CATERPILLAR TEN SLIDE 89 Fuel injection timing Fuel inj
113. nce 9 02 Remove O Ring aa Liv AR jy SLIDE 126 Remove the O ring Remove the O ring seal from the top of the injector The O ring seal Seal should be replaced every time the jumper tube is removed LEGV 4801 02 195 Slide T ext R eference 9 02 Remove Rockers sait SLIDE 127 Remove rocker arm Remove the rocker arm assembly Be sure to hold the rocker arm assembly assemblies together Only one end of the rocker arm is pinned LEGV 4801 02 196 Slide T ext R eference 9 02 Remove Connector CATERPILLAR LFY Geom SLIDE 128 Disconnect wiring Disconnect the wiring harness from the injector Care should be taken harness not to break the retaining clips on the connector A repair kit is available for connector replacement but it can be used only one time for an individual connector due to the length of the wire The weather pak seal should be replaced whenever the wiring harness is disconnected LEGV 4801 02 197 Slide T ext R eference 9 02 Remove Injector Ts CATERPILLAR SLIDE 129 Remove the injector Remove the injector from the cylinder head First try to remove it by hand If it can not be worked loose use the 1U 7587 pry bar to loosen the injector in the head CAUTION Pry only on the main body of the injector not the multi piece screwed on section as this could cause non warrantable injector failure L E G V 4801 02 198 Slide T ext R eference 9 02 3126 HEU
114. nd change the display numbers until the display shows 0062 00 mm H Push and hold the preset button until the flashing P is shown in the upper right corner of the display and then release M omentarily push the preset button so the flashing P and the zeros to the left of 62 00 mm disappear 1 Turn the indicator OFF The indicator will retain the preset number in memory only one preset number can be retained To recall the preset number repeat steps A D Then M omentarily push the preset button so the flashing P and the zeros to the left of 62 00mm disappear Install the 85mm long Contact Point 9U 7274 on the digital indicator stem Put Digital Indicator in the 9U 7308 Indicator Fixture Group until it stops Tighten nylon holding screw M ake sure the magnetic bottom of indicator fixture group and top and shoulder of Timing Gauge Block 9U 7269 are clean Place indicator and base assembly on the timing gauge block Once the base attaches let the plunger out Repeat steps A D and momentarily push the preset button until 62 00 mm appears LEGV 4801 02 146 Slide T ext R eference 9 02 ell indicator CATERPILLAR SLIDE 94 Adjusting the timing W hen the digital indicator and magnetic base are positioned on the dimension injector the indicator will display the current fuel timing dimension Refer to the engine information plate or TM I for the correct fuel timing dimension If the i
115. ndicator displays the correct dimension or within the 0 20mm tolerance no adjustments are necessary If indicator does not show the correct timing dimension turn the adjusting screw until the digital indicator displays the correct fuel timing dimension Tighten the locknut to 25 7 Nem 18 0 5 0 Ib ft and check adjustment again R epeat procedure if necessary until the adjustment is correct Check and adjust all of the injectors that can be done for the current engine position Rotate the engine 360 degrees and repeat the process for the remaining injectors LEGV 4801 02 147 Slide T ext R eference 9 02 Proper Tip Position n i it SLIDE 95 Install the magnetic Remove digital indicator and magnetic base from the gauge block and base on the Injector carefully position it on top of injector tappet for the injector to be checked M ake sure indicator contact point is on the shoulder of the injector and indicator plunger moves freely Assure that when the tip is raised the measured amount reduces LEGV 4801 02 148 L esson Plan 9 02 Small E ngine Fuel Systems Lesson Plan 10 Unit Injector Adjustment L ab Objectives e Inthe lab the student will demonstrate proper removal and assembly of a unit injector into the cylinder head e Inthe lab the student will demonstrate the ability to set injector synchronization to Specifications using the provided literature and tooling e Inthe lab the student will demons
116. ne arrangement Install a new gasket and the torque control group cover Then install the shutoff solenoid and connect the governor control linkage Reset low idle adjustment L E G V 4801 02 295 Slide T ext R eference 9 02 Remove Cam TDC Screw SLIDE 208 Remove transfer To remove the fuel transfer pump the fuel pump must be taken off the pump engine Remove the large bolt from the torque cover group L E G V 4801 02 296 Slide T ext R eference 9 02 insert Cam Pin CATERPILLAR SLIDE 209 Install timing pin Install the 3P 1544 timing pin and turn the injection pump camshaft until the timing pin drops into the groove This will stop the turning of the camshaft LEGV 4801 02 297 Slide T ext R eference 9 02 Rotate Pump SLIDE 210 Turn the 2H 3740 bolt that is found in the sleeve metering tool group into the end of the tapered drive adapter to remove it L E G V 4801 02 298 Slide T ext R eference 9 02 Remove Transfer Pump SLIDE 211 Remove bolts Remove the bolts in the transfer pump cover to the injection pump housing L E G V 4801 02 299 Slide T ext R eference 9 02 Inspect Gear O Ring CATERPILLAR Inspect gear amp seals Inspect the idler gear internal lip style seals in the camshaft bore and O ring seal L E G V 4801 02 300 Slide T ext R eference 9 02 Inspect Drive Assembly SLIDE 213 Inspect gear amp key Inspect the drive gear and key Reassemble the f
117. new what was happening the engine may have been seriously damaged by overspeeding This warning never operate a diesel engine without a governor controlling it is concerned with one of the purposes of governors to prevent engine overspeeding Governors also keep the engine at the desired Speed and increase or decrease engine power output to meet load changes L E G V 4801 02 47 Slide T ext R eference 9 02 Governor Mechanism SLIDE 21 Two basic Diesel engine mechanical governors consist of two basic mechanisms mechanisms the speed measuring mechanism and the fuel changing mechanism Speed measuring Fuel changing L E G V 4801 02 48 Slide T ext R eference 9 02 Flyweight Force CATERPILLAR Tram Leia Eon SLIDE 22 Speed measuring The speed measuring mechanism is simple has few moving parts and Flyweights measures engine speed accurately The flyweights and L shaped ball arms which pivot are mounted on the governor drive As the engine Ball arms rotates the flyweights rotate L E G V 4801 02 49 Slide T ext R eference 9 02 Flyweight Movement E S re i CATERPILLAR SLIDE 23 Flyweights rotate As the flyweights rotate they exert a centrifugal force outward The Centrifugal force flyweights move outward pivoting the ball arms upward The amount of outward force depends on the speed of rotation Centrifugal force is the basic operating principle of the soeed measuring me
118. ng set point rom CATERPILLAR Lit Geom L E G V 4801 02 73 Slide T ext R eference 9 02 POWER CURVES Boost Curve Boost Fuel Rate FTS N Boost Curve The maximum boost at a rom developed from the fuel rate curve ETON a a E 01 1 10 PA LOL High Idle 2262 CATERPILLAR TE SLIDE 43 Boost is a product of fuel rate The amount of fuel injected along with the availability of air produces exhaust gases which drive the turbocharger turbine The speed of the turbine determines the boost coming from the turbocharger This boost can then be diminished by leaks and restrictions L E G V 4801 02 74 Slide T ext R eference 9 02 POWER CURVES Increased Boost Curve Boost Improved Response RPM Governed speed 2100 High Idle 2262 CATERPILLAR gt SLIDE 44 Boost is directly proportional to responsiveness of the engine For efficiency the engine operating rom is normally a few rom above peak torque At this lower rom boost is lower since fuel rate is lower The engine although efficient is somewhat less responsive To combat this natural loss of response a wastegate turbocharger may be installed With the wastegate closed boost is elevated with the same fuel rate This improves the responsiveness of the engine at lower rpm As boost is elevated BM EP Brake M ean Effective Pressure Average cylinder pressure goes up If this pressure is allowed to get above engine limits premature engine
119. ntrifugal force of the governor flyweights is opposed by the A Rack B Governor spring C Thottle D Decelerator LEGV 4801 02 310 Test 9 02 14 The tolerance on the fuel setting measurements when adjusting the setting is A 0 00 mm B 0 10 mm C 0 25 mm D 0 50 mm E Noneof the above 15 BSFC Brake Specific Fuel Consumption is A Amount of fuel to produce rated horsepower for one hour B Pounds of fuel per horsepower minute C Pounds of fuel per horsepower hour D Gallons of fuel per horsepower hour 16 The hydraulic oil pump on a 3126B HEUI engine is a seven piston variable displacement axial piston pump A True B False 17 On a 7000 series nozzle the bleed screw is in the nozzle during the V OP test A True B False 18 When setting injector synchronization on a 1 1 liter engine the dial indicator is zeroed while the 1 rack is held at shut off A True B False LEGV 4801 02 311 Test 9 02 19 20 21 22 23 24 W hich of the following fuels will produce the most horsepower A JP4 B 39API 120 degrees F C 35 API 60 degrees F D 33 API 30 degrees F W hat Is the corrected API for 43 API 110 degrees F Fuel timing is checked on a 3116 engine using the 8T 5300 Timing Indicator Group A True B False W hat is the proper torque for the sleeve screw on the 3208 fuel pump A 2 8 foot pounds B 2 8 inch pounds C 25 inch pounds D
120. onents are located ECM amp wiring harness Hydraulic oil pump including the IA PCV and fuel transfer pump Oil Manifold The fuel comes from the fuel tank and primary fuel filter if equipped to the inlet of the fuel transfer pump mounted on the rear of the high pressure oil pump The fuel transfer pump sends the fuel to a spin on type secondary fuel filter Fuel from the fuel filter flows through a hard line to a drilled passage in the front of the cylinder head The drilled passage carries fuel to a gallery around each injector and provides a continuous flow of fuel to all of the injectors The unused fuel and any air exits the cylinder head at the rear and passes through a pressure regulating orifice and a check valve and returns to the fuel tank L E G V 4801 02 181 Slide T ext R eference 9 02 HEUI Fuel Systems Electronic Control Electronic Control Module i PA Module Coritk al migr trey ie HENTE Pb o a hz al Te i a opal e 7 A E TT T ECM Controls Personality Module Fuel Delivery FLASH Program Solnas Injection Pressure Updates Using Electronic Injection Timing Technician Service Tool IET SLIDE 113 ECM The ECM is a programmable on board computer which controls the Operation of the entire fuel system as well as other engine functions Because the ECM has many more operational inputs than a mechanical governor it can determine optimum fuel rate injection timing and injection pressure fo
121. osition C Moves the rack toward the fuel on position D Does not affect the fuel rack 6 The purpose of the fuel ratio control is to A Prevent turbocharger overspeed B Limit maximum horsepower C Eliminate excessive smoke during acceleration D To limit engine RPM until oil pressure builds up 7 What is or causes black smoke A Unburned fuel B Worn valve guides C Overfueling D Cracked cylinder liner 8 Whatis or causes white smoke A Burning oil Overfueling B C Incomplete combustion D A andC E None of the above LEGV 4801 02 13 Test 9 02 9 Which of the following can cause excessive black smoke A Advanced timing B High rack setting C A andB D None of the above 10 Which of the following can cause a low power complaint A Using 2 diesel fuel instead of 1 diesel fuel B Air inlet restriction of 15 inches of water C Exhaust back pressure of 10 inches of water D Mis adjusted or bent accelerator linkage 11 Which of the following can cause alow power complaint A Cloud point of the fuel too low B 37 2 API fuel and 90 degrees F C Cetane of the fuel too high D Increased altitude 12 A gallon of diesel fuel has more B T U s than a gallon of gasoline A True B False 13 The best way to lower cloud point of a diesel fuel A Add alcohol B Add gasoline C Add 1 diesel D Addcetane E All the above LEGV 4801 02 14 Test 9 02 14 15 16 17
122. out of the cylinder head and back to the fuel tank when the engine Is off LEGV 4801 02 185 Slide T ext R eference 9 02 Hydraulic Oil Pump amp SLIDE 117 Oil flow through the The oil flow throughout the engine is the same as 1 1 liter engines The engine oil for the hydraulic oil system exits the block low on the left side Hydraulic Oil Pump behind the air compressor and flows to the inlet of the high pressure oil IAPCV pump Hydraulic oil pressure is controlled by the IA PCV located on the back side of the oil pump Pressurized oil flows from the pump through Fuel Transfer Pump a hard line to the high pressure oil manifold The fuel transfer pump is driven from the HEU I oil pump and Is attached to the rear of of the hydraulic pump L E G V 4801 02 186 Slide T ext R eference 9 02 HEUI Fuel Systems Transfer Pump Low Pressure z Fuel System Supply Fual io HEU Injectors for Combestion s Supply Extra Fuel Flow for Cooling Injectors Supply Extra Fas Flea to Remowe Air from System CATERPILLAR SLIDE 118 Fuel Transfer Pump The fuel transfer pump is a cam actuated single piston pump which is mounted on the rear of the high pressure oil pump Fuel system pressure is maintained between 58 76 psi during normal operating conditions under load Fuel flows from the pump through the secondary and then through the cylinder head L E G V 4801 02 187 Slide T ext R eference 9 02
123. ove governer that is available with limited power The reason for this is for a smoother transition from full load to no load With different applications different droop percents work well Truck operations prefer 7 10 power generation requires 0 3 and other applications generally have 5 7 L E G V 4801 02 64 Slide T ext R eference 9 02 POWER CURVES Full Load Settin Full Load Setting The point at which governed power is produced and FLS is achieved in the governor Governed speed 2100 High Idle 2262 LFY Geom CATERPILLAR SLIDE 34 FLS Full load setting is the fuel rack position required to provide advertised governed power for an engine rating This setting is displayed on the engine data plate This is the point at which the full load screw is first in full contact with the stop or torque spring if equipped L E G V 4801 02 65 Slide T ext R eference 9 02 POWER CURVES Full Torque Settin Full Torque Setting The point at which maximum rack position is achieved Governed speed 2100 High Idle 2262 CATERPILLAR SLIDE 35 FTS As the engine is lugged below governed speed flyweight force lowers with a constant governer spring force This delta P of governor spring force would cause the rack position to increase Before movement can happen the force must first be great enough to bend the torque spring W hen the force is greater than the torque spring the rack position increases until th
124. p will move it The pour point is approximately 10 F below the cloud point The pour point can be improved with flow improvers or the addition of kerosene or a lighter diesel Fuel heaters cannot always solve problems related to a high pour point temperature since they normally use engine coolant as their heat source L E G V 4801 02 9 02 Fuel heaters E ngine performance E lectronic engines will adjust fuel rate 36 Slide T ext R eference Fuel Heaters SLIDE 13 A fuel heater will keep the wax dissolved and permit it to flow through the filters with the fuel Several types of fuel heaters are available on Caterpillar engines as factory installed options They can be installed between the fuel filter base and the spin on filter or between the fuel tank and fuel filter M ost of the heaters use engine coolant to heat the fuel and prevent ice or wax crystal formation in the filter Fuel heaters should only be used as required because as fuel temperature rises engine performance declines There is approximately a 1 horsepower loss for every 10 F increase in fuel temperature Fuel heaters should not be used if the ambient temperature is above 60 F and the fuel temperature at the outlet of the fuel heater should not be higher than 1650F Some electronic engines will adjust fuel rate depending on fuel temperature Fuel heaters used on electronic engines should be thermostatically controlled L E G V 4801 02 9 02 i
125. participants so the instructor can select the proper level to present the subject matter Literature Needed Registration Form Copy Small Engine Fuel System Schedule Copy Glossary of Terms LEX Q9297 Pre Test Copy H ardware Needed None Time R equired 1 Hour Tasks R equired by Instructor to M eet Objectives Fill out registration forms Introduce self and students Explain course objectives schedule and safety procedures Review how to use the Glossary of Terms PE eS YY a Administer and review pre test with the students LEGV 4801 02 11 Test 9 02 Small E ngine Fuel Systems Lesson Plan 1 Pre Test Select the best answer 1 Thespring force in a governor A Increases fuel rack hunting Does not affect the fuel rack B C Moves the fuel rack toward the fuel on position D Prevents rack movement E Moves the fuel rack toward the fuel off position 2 How can rated load rpm be increased A Increase the rack setting B Increase high idle C Increase fuel pressure D Increase the torque setting 3 If the A P I of the fuel is lowered the BTU content will go A Up B Down C Remain the same 4 Inthe hydra mechanical governor oil pressure is used to A Compress the governor spring B Lubricate governor parts only C Move the flyweights D Move the rack LEGV 4801 02 12 Test 9 02 5 The governor flyweights A Prevents fuel rack movement B Moves the rack toward the fuel off p
126. pikes would cause pressure variation and idle instability As the plunger rises pressure in the plunger cavity also drops to near zero The transfer pump pressure unseats the inlet fill check ball allowing the plunger cavity to fill with fuel The fill cycle ends when the intensifier is pushed to the top of its bore The plunger cavity is full and the fill check returns to its seat Pressure in the intensifier and poppet chambers is zero The injection cycle is complete and is ready to begin again Now that we have a good understanding of HEU operation let s briefly discuss another key difference between the HEUT and all other mechanically driven fuel systems That difference is that HEUI injection is time based and tends to compensate for leakage between the plunger and barrel In mechanical systems plunger speed is a function of crankshaft speed As wear occurs between the plunger and barrel the leakage rate increases This increased leakage results in reduced fuel delivery as wear becomes excessive L E G V 4801 02 9 02 210 Slide T ext R eference The HEU plunger is hydraulically driven and speed is a function of actuation pressure versus fuel pumping resistance If plunger and barrel wear increases leakage the fuel pumping resistance is reduced and the plunger will move faster and farther to compensate The result is that injection pressure will be maintained and the desired amount of fuel will be delivered through the no
127. provement additives which are quite expensive Also in current fuel injection systems the diesel fuel lubricates some of the fuel injection system components In addition alcohol does not have good lubrication characteristics L E G V 4801 02 9 02 39 Slide T ext R eference Fuel Sulfur CATERPILLAR Fuel sulfur Silent enemy Oxides of sulfur formed during the combustion process Acid formation Corrosive wear SLIDE 16 Caterpillar diesel engines have a silent enemy within diesel fuel sulfur Itis called the silent enemy because sulfur content does not directly affect engine performance It has no effect on engine Sstartability or power Sulfur content doesn t become a harmful factor until after the fuel has been burned During the combustion process sulfur dioxide SO gt and sulfur trioxide SO3 are formed These oxides of sulfur combine with the water vapor formed during combustion to create sulfuric acid This acid causes corrosive wear in engines and increases the chance of early engine failure L E G V 4801 02 40 Slide T ext R eference 9 02 Fuel Sulfur Test Specification Fuel Sulfur Content ASTM D129 standard fuel 0 5 ASTM D2622 low sulfur fuel 0 05 CATERPILL y Oh AR SLIDE 17 Sulfur content In the United States fuels which meet ASTM specifications for number Standard fuel 1 and number 2 diesel must contain no more than 0 5 sulfur by weight L ow sulfur fuel
128. pulse to the injector solenoid The solenoid is fully energized almost instantly creating a strong magnetic pull on the armature The armature is mechanically connected to the poppet valve by a screw The magnetic pull of the solenoid overcomes the spring tension holding the poppet closed and raises the poppet off its seat and at the same time closing the drain port W hen the poppet valve opens the upper poppet land closes the path to drain and the lower land opens the poppet chamber to incoming high pressure oil High pressure oil flows around the poppet through the passage to the top of the intensifier piston Pressure on the top of the intensifier forces it down along with the plunger The downward movement of the plunger pressurizes the fuel in the plunger cavity and nozzle W hen the pressure reaches Valve Opening Pressure V OP of about 4 500 psi the nozzle check valve lifts off its seat and injection begins LEGV 4801 02 207 Slide T ext R eference 9 02 CATERPILLAR TEn SLIDE 138 Main injection As long as the solenoid is energized the poppet remains open and Stroke limiting pressure oil continues to flow in pushing down the intensifier and plunger Injection pressure ranges from 5 000 23 000 psi depending on engine requirements Injection continues until one of the following conditions occur 1 The solenoid is de energized allowing the poppet spring to close the poppet and shut off the high pressure oil 2 The
129. pump was released Itis refered to as HEP which stands for High Effciency Pump The oil for the HEU fuel system is pumped and regulated by this unit Therefore the IA PCV has been eliminated LEGV 4801 02 250 Slide T ext R eference 9 02 HEP Cutaway SLIDE 164 Here the internal parts of HEP areshown This oil pump operates much like the Sleeve M etering Fuel System A sleeve is used to provide the required flow and pressure This is controlled by an internal valve much like the older IA PCV Toward the back of the HEP the gear type fuel transfer pump is found LEGV 4801 02 251 Slide T ext R eference 9 02 Fuel Transfer Pump eal Engin Training iv Gaon SLIDE 165 The fuel transfer pump is mounted on the rear of the HEP It is driven by the HEP shaft LEGV 4801 02 252 Slide T ext R eference 9 02 Fuel Transfer TET Pump yE id Cutaway Tizim E Liver CATERPILLAR SLIDE 166 Here is the cutaway of the gear type transfer pump with the relief valve This is the only servicable part of HEP Care should be taken when removing the transfer pump A bolt is provided in the transfer pump kit to hold HEP together during disassembly and assembly of the transfer pump from and to HEP LEGV 4801 02 253 Slide T ext R eference 9 02 HEUI Oil Pressure Sensor SLIDE 167 Asin other HEUI systems we need to know the actual pressure of the oil in the HEU manifold This is a direct controller of inje
130. r than VOP 209 Slide T ext R eference W hen the plunger stops fuel flow also stops With the check still open the remaining pressure on the fuel pushes a tiny amount of additional fuel out the orifice holes This causes a large pressure drop which lowers nozzle pressure below Valve Closing Pressure V CP of 2 700 psi Spring tension on the check now reseats the check and injection stops Instructor N ote V CP is lower than V OP because more surface area of the check is exposed to pressurized fuel when the check is off its seat W hen the check closes injection stops and the fill cycle starts The poppet and intensifier cavities are open to atmospheric pressure through the poppet valve and adapter drain hole Pressure drops very rapidly in the intensifier and plunger cavities to near zero The plunger return spring pushes upward on the plunger and intensifier forcing oil around the poppet through the holes in the poppet sleeve and out the adapter drain hole As the intensifier moves up the barrel ball check closes to prevent fuel from filling the area under the intensifier This causes a partial vacuum in this area so that the volume of fuel is about 3 4ths of cavity volume This feature prevents a high pressure spike in the fuel rail when the injector fires If this cavity was filled with fuel a large volume would be forced back into the fuel rail as the intensifier rapidly moved downward during injection The resulting pressure s
131. r almost any condition Electronic controls such as this are absolutely essential in meeting new standards of exhaust emissions and noise Solenoid drivers in the ECM send a precisely controlled current pulse to the injector solenoid which energizes the solenoid The magnetic field created by the solenoid lifts the poppet valve off its seat which starts the injection cycle The timing duration and current level of this pulse are controlled by logic circuits inthe ECM Fuel rate is a function of pulse duration and injection actuation pressure L E G V 4801 02 182 Slide T ext R eference 9 02 HEUI Fuel Systems Pressure Temperature Sensors Sensors otia a Position Speed Sensors SLIDE 114 For the ECM to control it must recieve multiple inputs These inputs are supplied by the various sensors on the engine Their operation and troubleshooting will be covered in Electronics courses LEGV 4801 02 183 Slide T ext R eference 9 02 3126 Rear Engine CATERPI SLIDE 115 E ngine Rear The fuel return check is located in the rear of the cylinder head L E G V 4801 02 184 Slide T ext R eference 9 02 Outlet Check Valve CATERPILLAR SLIDE 116 Fuel Return Check The fuel return check has a 0 5 mm orifice that maintains fuel pressure 0 50 orifice in anormal operating range of 58 to 75 psi The fuel pressure at low idle should be approximately 58 to 63 psi The check valve prevents the fuel from draining
132. r the fuel for that cylinder The plunger is actuated by a mechanical drive train This drive train requires an additional cam lobe lifter push rod and rocker arm for each cylinder Fuel is metered by a scroll type plunger in the unit injector which is controlled by mechanical linkage to the governor LEGV 4801 02 168 Slide T ext R eference 9 02 MUI Fuel Systems Mechanical Unit Injector Advantages High pressure fuel lines are eliminated EAN DKN inject at up to 23 000 psi Limiting Factors No timing advance Mechanical actuation amp governor control SLIDE 102 The major advantage of this system is the elimination of the high pressure fuel lines However the ability to precisely meter the fuel for varying conditions is limited by the capabilities of the mechanical governor Since the M UI is activated by the engine camshaft timing advance is also not available LEGV 4801 02 169 Slide T ext R eference 9 02 EUI Fuel Systems Mechanically Actuated Electronic Unit Injector A unit injector is positioned above each cylinder An Electronic Control Module ECM controls fuel rate and timing Injectors are mechanically actuated by a camshaft CATERPILLAR SLIDE 103 The Electronically Controlled M echanically A ctuated U nit Injector EUI has some additional advantages W hile this system still requires a mechanical valve train to actuate the plunger the fuel is metered electronically by m
133. r time The injector nozzle serves as a high pressure check valve which atomizes the high pressure fuel for combustion and prevents residual fuel from leaking into the cylinder LEGV 4801 02 166 Slide T ext R eference 9 02 Pump amp Lines Fuel Systems Limiting Factors High pressure fuel lines Fuel rate amp timing control SLIDE 100 Pump and lines systems are very reliable and durable but are structurally limited to about 18 000 psi maximum injection pressure They also have limited injection timing and injection rate capabilities Current engine emissions and performance requirements at times demand injection pressures in excess of 20 000 psi and greater timing flexibility to met today s emissions standards LEGV 4801 02 167 Slide T ext R eference 9 02 MUI Fuel Systems Mechanical Unit Injector A unit injector Is positioned above each cylinder A mechanically actuated governor controls fuel rate scroll metered with flyweights and springs Timing is fixed CATERPIL SLIDE 101 The mechanical unit injector system was at one time used only on very large bore engines to eliminate the need for long high pressure fuel lines and the related problems inherent with controlling pressures in these fuel lines The mechanical unit injector M UI contains a nozzle assembly which performs the same function as a fuel injection nozzle The MUI also contains a plunger and barrel to pressurize and mete
134. ral other fuel systems we have used coming to this point In the following few slides we will look at these various systems with both their good points and some of their limitations L E G V 4801 02 9 02 164 Slide T ext R eference Pump and Lines Fuel Systems RPIL Hardware includes multi plunger high pressure pump fuel lines amp fuel nozzles A mechanically actuated governor and timing advance unit control fuel rate amp timing with flyweights and springs Can inject fuel from 5 000 to 17 000 psi SLIDE 99 The most common fuel system used on heavy duty diesel engines is the scroll type pump and lines direct injection system Direct injection means the nozzle sprays fuel directly into the combustion chamber rather than through a prechamber Direct injection systems offer improved performance emissions and economy but requires higher injection pressures and better control of fuel atomization This system has three main components Multiple plunger pump High pressure fuel lines Fuel injection nozzles The pump housing contains a cam actuated plunger and barrel assembly for each engine cylinder The plunger and barrel pressurizes and meters the precise amount of fuel needed for each cylinder The high pressure fuel pulse is mechanically timed so that it travels through the high L E G V 4801 02 9 02 165 Slide T ext R eference pressure fuel line and opens the injection nozzle at the prope
135. rence 9 02 Governor Back CATERPILLAR Engines mining Liivi SLIDE 68 Torque cam On types one through four governors a torque cam adjustment must be adjustment made prior to assembly This adjustment can be made after the rear Types 1 through 4 housing is assembled and mounted on the stand To make this Torque cam lever adjustment the seal shown in the illistration should be removed There is no internal torque cam adjustment on types five through eight governors Grasp the riser lever and rotate clockwise until torque cam lever clears torque cam lever shoulder in torque cam M ove the torque cam lever over the shoulder in torque cam Rotate the riser lever counter clockwise until the torque cam lever contacts the shoulder in the torque cam LEGV 4801 02 114 Slide T ext R eference 9 02 Torque Cam Setting ty k ok CATERPILLAR SLIDE 69 Torque cam Using two bolts furnished in the 1U 7315 tool group install the 1U 7310 adjustments fixture onto the housing Install the 5S8086 contact point into the Install tooling 6V 6106 dial indicator or digitial indicator Install the dial indicator into Zero indicator fixture until it bottoms out The tip of the dial indicator should rest on the edge of riser lever Place the 1U 7311 allen wrench furnished in the 1U 7315 tool group into torque cam setscrew Using the wrench as a lever rotate the torque cam clockwise until riser lever swivel contacts the post on the f
136. ressure Sensor monitors actuation pressure in the oil manifold and the 725 to 3335 psi ECM compares actual pressure to desired pressure If these pressures do not match the ECM adjusts the current level to the IA PCV to compensate OIL FLOW ENGINE RUNNING Pump outlet pressure red enters the end of the valve and a small amount of oil flows into the spool chamber through the edge filter and control orifice in the spool chamber The pressure in the spool chamber is controlled by the force on the poppet and allowing it to bleed off some of the oil in the spool chamber The force on the poppet is controlled by the strength of the magnetic field produced from the electrical signal from the ECM The spool responds to pressure changes in the spool chamber left side of the spool by changing positions to L E G V 4801 02 9 02 219 Slide T ext R eference maintain a force balance between the right and left side of the spool The spool position determines how much area of the drain ports are open The drain port open area directly affects how much oil is bled off from the pump outlet and directly affects rail pressure The process of responding to pressure changes on either side of the spool occurs so rapidly that the spool is held in a partially open position and pump outlet pressure is closely controlled The IA PCV allows infinitely variable control of pump outlet pressure between 725 psi 5M Pa and 3 335 psi 23 M Pa L E G V 4801 02
137. s Standard fuel and low sulfur fuel It should be noted that the only variation between the two columns is the amount of sulfur contained in the fuel Each type diesel fuel fuel oil furnace oil kerosene of preferred fuels can be put into either category depending on sulfur content Standard fuel 0 5 sulfur maximum 5 000 parts per million is available for off highway use in heavy equipment industrial engines and commercial marine applications in the United States and Canada For identity of this fuel the governments require a dye to be added Low sulfur fuel 0 05 sulfur maximum 500 parts per million is required for use on highway trucks and pleasure craft marine applications in the United States and Canada No dyeis added to this fuel It is almost clear with a slight yellow green tint L E G V 4801 02 9 02 28 Slide T ext R eference As emission standards get tighter new fuels are already available The next step will be diesel fuels with 0 015 sulfur maximum 150 parts per million These fuels will be required for on highway use in 2007 They are currently in use for ultra low emissions vehicles L E G V 4801 02 9 02 CATERPI Permissible fuel Crude oil Blended fuel Serviced life Treatment Centrifuge H eating Reducing life Increased maintenance 29 Slide T ext R eference Permissible Fuels Crude Oils Blended Fuels LLAR TE SLIDE 6 The use of some crude oils and blended fuels
138. s must also have a basic knowledge of diesel engine systems Priority will be given to individuals designated by dealerships to become a Certified Engine Instructor Students attending will be asked to bring approved safety glasses and wear only rigid style shoes No canvas tennis shoes or open toe shoes Students should also bring a calculator L E G V 4801 02 9 02 Day Sec M onday 1 Tuesday 7 10 11 Wednesday 12 Subject Small E ngine Fuel Systems Schedule Introduction and Pre Test Fuel Selection B reak Fuel Selection Fuel Related Problems Lunch Fuel Related Problems Basic Governor Theory Performance Curves B reak Horsepower Correction Factors Quiz 1 Fuel Setting Information B reak 1 1 1 2 MUI Fuel System Introduction Injector Adjustment L ab Lunch Injector Adjustment L ab B reak Injector Adjustment L ab Governor Disassembly amp Assembly Governor Disassembly amp Assembly Quiz 2 Slide T ext R eference Time 8 00 9 00 9 30 9 45 10 30 11 00 11 45 12 15 12 30 2 30 2 45 8 00 8 30 9 30 9 45 11 00 11 30 1215 2 30 2 45 3 00 8 00 9 00 9 00 9 30 9 45 10 30 11 00 11 45 12 15 12 30 2 30 2 45 4 00 8 30 9 30 9 45 11 00 11 30 12 15 2 30 2 45 3 00 4 00 9 00 9 30 L E G V 4801 02 4 Slide T ext R eference 9 02 B reak 9 30 9 45 13 Governor Test Stand Lab 9 45 11 30 Lunch 11 30 12 15 Governor Test Stand Lab 12 15 12 45 1
139. s of water sediment and trace metals the owner may need to monitor and evaluate oil change intervals and use extra filtration to remove solids and or install fuel heaters and centrifuges to make the fuel pumpable Also note the difference in sulfur content between crude oil and the blended fuel L E G V 4801 02 31 Slide T ext R eference 9 02 Sediment Disposal CATERPILLA Draining Hiv ieom SLIDE 8 Fuel storage tanks Crude oil blended fuel and even distilled fuels may contain excessive Tank construction amounts of water and or sediment which require pre treatment before delivery to the fuel injection system Some of these contaminants can be removed by using a settling tank Fuel storage tanks should be Waste handling constructed on an angle so water and sediment will settle in the low end Contaminants can then be drained off periodically Care must be taken when disposing of the material drained off since it is considered hazardous waste in some areas Water in the fuel storage tanks can also lead to the growth of bacteria These bacteria can plug fuel filters Causing low power in engines Storage tanks should be checked for bacterial growth There are fuel and water soluble additives which can be added to storage tanks to control bacteria Drained periodically L E G V 4801 02 32 Slide T ext R eference 9 02 Water Separators CATERPIL SLIDE 9 W ater separator The water separator should be installed betw
140. s seat for injection and once pressure drops a spring closes the check Fuel surrounds the injector from the top o ring to the raised sealing ring at the base of the nozzle cone L E G V 4801 02 9 02 Remove the unit injector Drain fuel Hold down bolt Do not pry on clamp 99 Slide T ext R eference MUI Injector Removal SLIDE 56 To remove the unit injector first drain the fuel from the cylinder head to prevent fuel from entering the cylinder when the injector is removed This is particularly important if a catalytic converter is installed since raw fuel can cause damage to them Remove the Injector hold down bolt Then being careful not to damage the injector rack insert the pry bar in the notch at the base of the injector and loosen the injector in the bore Do not pry on the injector hold down clamp since this would distort it Rotate the injector clockwise to assure that the rack head clears the rack shaft before removing the injector L E G V 4801 02 9 02 G overnor Flyweight type Floating fulcrum Bench testing 100 Slide T ext R eference Governor i mmu SLIDE 57 The governor is mounted high on the left side on the front housing of the engine It is driven by the cam gear in the front gear train Fuel rate and engine speed are controlled by linkage connected to the injector rack The governor is a flyweight type full range with a floating fulcrum linkage which allows for a small package
141. system on a 3208 is uses a D A scroll type B mechanical unit injector C electronic unit injector D sleeve metering type 4 An engine has a torque of 505 pound feet at 2600 rom What horsepower is it developing hp 505 X 2600 5252 hp 250 LEGV 4801 02 314 9 02 Which of the following can cause excessive black smoke High idle set too low High fuel setting A and B BandC A B C Injector timing dimension 0 5 mm high D E F All the above The best way to lower cloud point of a diesel fuel is C A Add alcohol B Add gasoline C Add 1 diesel D Add cetane E All the above Fuel dilution in a 1 1 liter engine can be caused by A A A cut injector o ring B A loose bleed screw in 7000 series nozzle C A broken transfer pump valve D All the above One gallon of diesel fuel 37 API 60 degrees F weighs A 7 206 Ibs B 7 001 Ibs C 6 993 Ibs D 6 910 Ibs Test L E G V 4801 02 315 Test 9 02 9 Engine fuel settings should be adjusted to compensate for power loss with lighter fuels B never A True B False 10 Always pour clean fuel into a new fuel filter element before you install it B never A True B False 11 The most accurate fuel setting information can be found C A TheOT 2T 0K fiche The Technical Information File B C Onthe Engine Information Plate D In the Service M anual E Inthe Testing and Adjusting M anual 12 T
142. t Bench maintenance SLIDE 72 AII of the adjustments for the governor must be done on the governor calibration bench If the low idle is not satisfactory the locknut can be loosened and the low idle can be set in chassis by turning the adjusting screw After making the adjustment tighten the locknut There is no set point measurement capability The full load speed is adjusted on the test bench The calibration bench weighs approximately 150 pounds It has a 50 or 60 cycle 1 2 hp electric motor and digital tachometer Ten weight oil is used to lubricate the governor during testing Proper maintenance must be done on the bench prior to use Check the oil in reservoir and variable speed drive Install the governor on the calibration bench Install three fittings fuel in fuel out and oil Install four fittings if governor is equipped with fuel ratio control Connect the oil lines to fittings Install the lever on the throttle lever and install return spring LEGV 4801 02 120 Slide T ext R eference 9 02 CATERPILLAR igir z livi SLIDE 73 Calibration dimension Puta1U 8815 contact point on the stem of the 6V 6106 dial indicator Special procedure Install the dial indicator into bracket The dial indicator is used for setting the load stop adjustments and must be set at the calibration M ore than 9 00mm dimension 8 00 mm on most governors before bench testing If the load stop measurement is more than 9 00 mm a speci
143. t restriction of 15 inches of water Exhaust back pressure of 10 inches of water Mis adjusted or bent accelerator linkage 11 Which of the following can cause alow power complaint A B C D 12 A A B 13 T Cloud point of the fuel too low 37 2 API fuel and 90 degrees F Cetane of the fuel too high Increased altitude gallon of diesel fuel has more B T U s than a gallon of gasoline True False he best way to lower cloud point of a diesel fuel Add alcohol Add gasoline Add 1 diesel Add cetane All the above Test LEGV 4801 02 19 Test 9 02 14 A diesel fuel with a low cetane number can result in E A Hard starting White smoke at startup Black smoke under load Fuel filter plugging A and B A and C nm o O W 15 The high idle adjustment can be made on the engine on a 3116 engine B A True B False 16 The purpose of transfer pump pressure is C A to increase engine horsepower B to disipate the water in the fuel C to properly fill the plunger and barrel assemby D to prevent filter plugging 17 The horsepower tolerance for a Caterpillar engine with less than 100 000 miles Is B A 5 B 3 C 5 3 D 7 5 LEGV 4801 02 20 Test 9 02 18 As inlet fuel temperature increases B A Maximum horsepower of the engine increases B Maximum horsepower of the engine decreases C Boost pressure increases D The fuel becomes more dense 19 Itis recommende
144. test The student will be able to calculate specific weight of a fuel with at least 70 accuracy on a written test The student will be able to calculate expected horsepower loss or gain due to fuel API with at least 70 accuracy on a written test The student will be able to explain operation of a fuel sight glass with at least 70 accuracy on a written test The student will be able to explain the use of various fuel heaters and Caterpillar s stance on methods of mixing oil and fuel with at least 70 accuracy on a written test Literature Needed Diesel Fuel and Your Engine SEBD0717 Engine Performance Reference LEXT1044 Blending Used Crankcase Oil LEK Q6070 Blending Used Crankcase Oil for use with Cat HD Diesel Engines LEK Q6071 H ardware Needed Chalk W hite board 1P7408 T hermo hydrometer 5P2712 Thermo hydrometer 1P 7438 Beakers Various fuel samples Time R equired 1 Hour LEGV 4801 02 43 L esson Plan 9 02 Tasks R equired by Instructor to M eet O bjectives 1 Using Diesel Fuels and Your Engine SEBD0717 Emphasize the following points A How fuel quality relates to power complaints B Explain fuel API specific gravity and density See page 6 of Diesel Fuel and Your Engine 1 Explain the method of using a thermo hydrometer 2 Explain the fuel meniscus C Converting fuel API degrees to specific weight See page 7 of Diesel Fuel and Your Engine 2 Using Horsepower Correction Factors emphas
145. the outside of the pump for easier access of valve replacement Other than these two changes the pump is primarily the same LEGV 4801 02 225 Slide T ext R eference 9 02 SLIDE 150 ECM The 3126B E is equipped with the ADEM 2000 Electronic Control Seventy Pin Module The ADEM 2000 is equipped with two seventy pin Connectors connectors The connectors used on the wiring harness are a Deutsch type The ECM Terminals in the connector must be gold This ECM also has a faster processor than the ADEM 2 allowing for more customer features F aster processor ECM terminals must be gold L E G V 4801 02 226 Slide T ext R eference U Solenoid Injector Components Poppet Valve intensifier Piston Nozzle Assembly CATERPILLAR SLIDE 151 The HEUI injector has several different configurations The one used on the 3126B E is the H1300 This stands for Hydraulic Injector A ngled 300 cubic millimeters per stroke displacement The HEUI is hydraulically actuated by high pressure engine oil supplied by a fixed displacement axial piston pump Pump outlet flow and pressure is controlled by an electronic pressure relief valve IA PCV The HEUI injector has five major components SOLENOID The solenoid is an electromagnet When the solenoid is energized the solenoid creates a very strong magnetic field This magnetic field attracts the armature which is connected to the poppet valve by an armature screw When the arm
146. tion pressure D A and B E B and C F A andC G All the above 8 Whic of the following are standard conditions for a 3126 J WAC marine engine A 35API 60 degrees F B 110 degrees F intake manifold temperature C 30 5 Hg barometer D A and B E A andC F BandC G All the above LEGV 4801 02 241 Test 9 02 9 In most cases using the 173 1530 injector seating tool group eliminates the need for using a roll burnisher when changing injector sleeves A True B False 10 The 173 1530 injector seating tool group is used on all the following engines except A 3114 and 3116 MUI B 3116 HEUI C 3126 HEUI D 3126B E HEUI L E G V 4801 02 242 Test 9 02 SMALL ENGINE FUEL SYSTEMS L esson Plan 16 Quiz 3 Select the best answer If the answer is false on a true false question corredt the question to make it true 1 The available operating pressure range for the hydraulic oil pressure in a 3116 HEUI engine is C A 625 to3335 psi B 725 to 3000 psi C 725 to 3335 psi D 600 to 3335 psi 2 Thefuel ratio control on a Type ll 3116 governor is not in a restrictive position during cranking B This type takes boost to move it out of restrictriction A True B False 3 A 3126B HEUI engine will not start until the injection actuation pressure has reached C A 735 psi B 780 psi C 870 psi D 3000 psi 4 The horsepower tolerance of a new engine at governed speed is D A 5 B 3 5 C
147. trate the ability to time injectors to the proper height using the provided literature and tooling e Inthe lab the student will demonstrate the ability to make power settings on the engine using the provided literature and tooling Literature Needed Systems Operation Testing and Adjusting 3114 3116 amp 3126 SENR 3583 Using the 128 8822 Tool Group on 3114 3116 amp 3126 Engines NEHS0610 H ardware Needed 1 1 or 1 2 Engine 128 8822 Tool Group M etric Hand Tools Time Required 3 Hours Tasks R equired by Instructor to M eet O bjectives 1 Theinstructor is to change the injector timing synchronization and power setting for the training engine prior to the class 2 Have the students remove injector 1 and 2 Replace them switching positions of the injectors 3 Using the listed injector tool group have the students synchronize all injectors Assure that each student has opportunity to synchronize at least one injector using the tool group 4 Timeall injectors Assure that each student has opportunity to time at least one LEGV 4801 02 149 L esson Plan 9 02 injector If time is available have the students check and set valve lash 5 Adjust the power setting This may be repeated until all students have had an Opportunity to adjust the fuel setting LEGV 4801 02 150 L esson Plan 9 02 Small E ngine Fuel Systems Lesson Plan 11 1 1 and 1 2 Governor Disassembly and Assembly Objectives e Thest
148. udent will be able to disassemble assemble and make appropriate internal adjustments of the 1 1 and 1 2 Liter Engine Governor given proper tooling and literature Literature Needed Service M anual 3114 3116 3126 Engine Governor SENR 6454 Hardware Needed 1 1 or 1 2 Liter Engine Governor 128 8822 1 1 Liter Engine Injector Tool Group 1U 7315 1 1 Liter Engine Governor Tool Group M etric Hand Tools Time Required 2 Hours Tasks R equired by Instructor to M eet O bjectives 1 Remove the governor from the engine if required 2 Using the disassembly procedure in the service manual disassemble the governor halves After the governor has bee separated have the students miss adjust anything that can be later adjusted 3 Have the student look up the Governor Performance Data from TMI 4 Using the assembly procedure in the service manual and the Governor Performance Data from TM I adjust and assemble as required the governor LEGV 4801 02 151 L esson Plan 9 02 Small E ngine Fuel Systems Lesson Plan 12 Quiz 2 Objectives e The student will take a quiz to review and test the previous day s material A minimum of 70 accuracy is considered acceptable Literature Needed Quiz 2 Copy H ardware Needed None Time R equired 0 5 Hour Tasks R equired by Instructor to M eet Objectives 1 Ask student for questions regarding material covered the previous day 2 Answer all questions using reference mat
149. uel transfer pump R eassemble LEGV 4801 02 301 L esson Plan 12 01 SMALL ENGINE FUEL SYSTEMS L esson Plan 19 3208 Fuel System L ab Objectives e The student will be able to remove and install a 3208 fuel pump and governor from the engine e The student will be able to completely disassemble and assemble the fuel pump and governor and make appropriate internal adjustments of the pump and governor given the proper tooling Literature Needed 6V 4141 Sleeve Calibration Tool SM HS7835 5P6577 Fuel Setting Tool Group SM HS7013 Hardware Needed 3208 Engine with Pump and Governor 6V 4141 Sleeve Calibration Tool Group 5P6577 Fuel Setting Tool Group Hand Tools Time Required 1 5 Hour Tasks R equired by Instructor to M eet Objectives 1 Remove the fuel pump and governor from the engine if required 2 Using the literature provided disassemble assemble and adjust as required the fuel pump and governor 3 Re install the fuel pump and governor on the engine if required LEGV 4801 02 302 L esson Plan 12 01 SMALL ENGINE FUEL SYSTEMS L esson Plan 20 Introduction to Fuel Lines and Nozzles Objectives e The student will be able to identify the difference between failure modes of fuel lines on a written test with at least 70 e The student will be able to identify the difference between nozzle types nozzle application and failure modes of fuel fuel injection nozzles on a written test with at least 7
150. uiz 1 Select the best answer If the answer is false on a true false correct the question to make it true 1 The largest single operating expense over the life of an engine is D A Purchase price B Repairs C Preventive maintenance D Fuel 2 Specific gravity API of fuel is measured with a C A Hygrometer Thermometer B C Hydrometer D Pyrometer z Viscometer 3 The standard fuel API for CAT diesel engines is D A 35 API 50 F B 41 API 60 F C 38 API 50 F D 35 API 60 F L E G V 4801 02 88 Test 9 02 4 One gallon of diesel fuel A PI 39 60 F weighs D A 7 206 Ibs B 7 000 Ibs C 7 076 Ibs D 6 910 Ibs Engine fuel settings should be adjusted to compensate for power loss with lighter fuels B should not A True B False Cetane number indicates the BTU content of a fuel B Ignition quality A True B False The pour point of a fuel indicates the temperature at which wax crystals begin to form B Cloud Point A True B False High sulfur content in diesel fuel can result in F Excessive liner wear High power output High oil consumption B C and D A C andD A B C D Excessive blowby E F G All of the above L E G V 4801 02 89 Test 9 02 9 What is the corrected A PI of a fuel that has a measured value of 43 API at 30 F 45 6 API 60 F 10 Always pour clean fuel into a new fuel filter element
151. under the valve cover W hen the downward travel of the plunger stops fuel flow also stops W hile the check is still open the remaining fuel pressure pushes a small amount of fuel out of the orifice holes This causes a large pressure drop which lowers injection pressure below Valve Closing Pressure VCP Spring tension on the check now reseats the check into the tip and injection stops W hen the check closes injection stops When injection stops the fill cycle starts The area above the intensifier piston cavity is open to atmospheric pressure through the upper poppet seat Pressure drops very rapidly in the cavity above the intensifier piston to near zero The return spring of the plunger pushes up on the intensifier piston As the plunger and the intensifier piston move upward oil is forced around the upper poppet seat After the oil is forced around the upper poppet seat the oil is forced out of a vent hole As the plunger rises pressure in the plunger cavity also drops to near zero The fuel supply pressure is 450 kPa 65 psi Fuel supply pressure unseats the plunger fill check in order to fill the plunger cavity with fuel When the intensifier piston is pushed to the top of the bore the fill cycle ends When the fill cycle ends the plunger cavity is full and the inlet fill check ball is reseated Pressure above the intensifier piston and the poppet chamber is zero The fuel injection cycle is complete and the unit injector is re
152. ve L E G V 4801 02 161 Slide T ext R eference 9 02 1 1 and 1 2 HEUI Fuel Systems CATERPILLAR HEUI fuel system This presentation introduces the 3116 3126 HEU fuel system It will cover the operation of the fuel system and the mechanical components of the engine We will touch on the HEU electronics but not cover them in great detail We will start with the 3116 3126 system and then move to the 3126B E system LEGV 4801 02 162 Slide T ext R eference 9 02 Hydraulically actuated Electronically controlled Unit Injector CATERPILLAR SLIDE 97 H E U I HEUI stands for Hydraulically actuated Electronically controlled Unit Governor Injector It differs from the 3116 and 3126 M UI system in two ways Hydraulically First the M UI system uses a mechanical governor to control the rack actuated and fuel rate the HEU I fuel system is controlled by an electronic governor ECM All of the functions performed by the mechanical governor are now done by an ECM electronic control module Also the M UI fuel system uses a camshaft pushrod and rocker arm assembly to actuate the injector or inject the fuel into the cylinders The HEU fuel system uses hydraulic oil pressure to move the plunger LEGV 4801 02 163 Slide T ext R eference 9 02 How Did We Get Here CATERPILLAR SLIDE 98 Over the years fuel system technology has dramatically evolved Today we use HEU fuel systems but there have been seve
153. wer poppet seat blocks high pressure actuation oil from entering the unit injector The plunger and the intensifier piston are at the top of their bores and the plunger cavity is full of fuel Fuel pressure in the plunger cavity is equal to the fuel transfer pressure The fuel transfer pressure is approximately 450 kPa 65 psi L E G V 4801 02 231 Slide T ext R eference 9 02 HEU Pilot Injection J P Plunger PRIME Spill Port CATERPILLAR SLIDE 154 Pilot Injection PRIM E The 3126B E diesel engine fuel system has a unique feature that is called PRIME Pre Injection M etering PRIM E is a feature that offers a significant benefit in lower emissions Also PRIME offers a significant benefit in reducing combustion noise W hile other fuel systems deliver a single large quantity of fuel into the combustion chamber PRIME injectors break the delivery into two separate quantities The first quantity is a small pilot injection which is followed by a short delay Then the injector delivers a large main injection The pilot injection is intended to establish a flame front The pilot injection will help the larger main injection burn more completely and in a more controlled fashion L E G V 4801 02 232 Slide T ext R eference 9 02 Solenoid era Poppet Valve Intensifier Piston Delay CATERPILLAR SLIDE 155 Delay The PRIM E feature produces a small pilot injection that is followed by a brief delay The brief de
154. y time during the downward stroke of the plunger An electronic control module ECM actuates the solenoid operated spill valve Second this system has higher injection pressure capability than any other system The 3406E C 15 C 16 injectors produces up to 30 000 psi injection pressure for maximum fuel atomization Finally the electronic control can sense road speed load and several other inputs to provide better part throttle performance improved fuel economy and lower emissions L E G V 4801 02 172 Slide T ext R eference 9 02 EUI Fuel Systems Mechanically Actuated Electronic Unit Injector System Limiting Factor Injection pressure is dependent on engine speed rom SLIDE 105 As with the multiple plunger system however injection pressure is determined by the speed of the plunger pushing the fuel through a fixed orifice the nozzle There is a direct relationship between engine speed plunger speed and the resultant injection pressure It is desirable to achieve maximum injection pressure at peak torque engine speed However since peak torque speed is less than rated speed injection pressure is also less For the 2000 s we need a fuel system that will produce high injection pressures at any engine load or speed Demands for greater fuel economy and lower exhaust emissions in the 2000 s require vastly improved fuel system performance The HEUI meets these requirements LEGV 4801 02 173 Slide T ext
155. zzle even though leakage has increased This remains true until wear becomes so severe that the plunger cannot accelerate fast enough during short injections to compensate or the plunger literally runs out of travel when the intensifier piston bottoms out against the barrel L E G V 4801 02 9 02 sait Injector replacement Poppet seat alignment 211 Slide T ext R eference Pi Ho F ih a HOF SLIDE 140 This completes the mechanical operation of the injector Now let s discuss injector servicing INJECTOR REPLACEMENT If injector replacement is necessary the injector is replaced as a unit There are no serviceable parts on the injector except the 0 rings on the outside DO NOT attempt to disassemble the injector under any circumstances A performance test and detailed analysis will be done on every injector returned from the field Injector disassembly will cause the injector to be non functional and fail the performance test Itis very easy to determine if an injector has been disassembled or abused during removal Let s take a few minutes to discuss why POPPET SEAT ALIGNMENT The injector poppet valve has an upper and lower seat which must both L E G V 4801 02 9 02 212 Slide T ext R eference seal perfectly for the injector to work The poppet is guided by upper and lower guides The lower guide is ground into the body below the lower seat The upper guide is ground into the poppet s

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