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mitsubishi diesel engine model 4dq5ow

1. 31 Governor Model RSV bosch 34 4 8 Automatic timer 2 2 22 ce eee ee ee RII 45 4 9 Measurement of engine speed 46 Cooling System 2 ceed le e ee sm yk oie e s 48 5 1 Cooling water and radiator M 48 5 2 Thermostat RD ERU ERU RR e Da ee 49 5 3 Tension of fan belt 49 Electric system viro ea eg ver RIPE WE TIR OR ates WIRE 50 1 DC 22 5 or um rm alee eee eee a ale wie ka eR A 51 6 2 A C Generator 52 6 2 1 D C Generator Relay 53 6 2 2 Generator Relay 53 6 3 Starter eie cre La EA Per Eee pro Pese aE 53 6 4 Battery cuo eec REA WEN US E be a Pe SS 54 7 Re screwing of main bolts 55 7 1 Cylinder head clamp bolts 56 7 2 Main bearing caps and connecting rod caps 56 7 3 Oers iiv SEA E ewe aw He SE Ce ete had 56 CHAPTER 4 5 1 59 1 Trouble shooting chart 60 2 Trouble shooting chart Appendix 64 CHAPTER 5 OVERHAULING INSTRUCTIONS 69 1 General
2. Control rock Governor spring Swivel lever Fig 7 The highest revolving position of the control lever In this case the swivel lever of course stretches the governor spring fully Accordingly the governor spring stretches the tension lever with its large power to the full load stopper and transfers the control rack to the full load position The r p m of the engine rises and the control r p m and the centrifugal force also increase In this governor in which the ungleich device is involved when the tension lever comes Full load the work of ungleich ends Control lever Control rack Governor spring Swi vel lever Ungleich spr ing Shifter amp Guide bush Full load stopper Fig 8 Starting of the highest r p m control Full load No load idie START STOP Flooting lever Guide lever Tension lever Swivel lever y Shifter amp Guide bush Full lood stopper Fig 9 The case as controlled at the non load condition 49 in touch with the full load stopper shifter will directly came in touch the tension lever along with the rise of r p m Accordingly the ungleich spring will be pressed under a fixed condition Fig 8 Fig 9 With the result of such movement as above the guide lever and the control rack move in the STOP direction up to the corresponding volume of ungleich and ungleich the jet volume When the machine reaches the full load and the centrifugal force wins over th
3. to see how soon it will drop i kg cm If it takes longer than 5 sec oil tight ness is satisfactory not less than 5 sec Conditions Nozzle tips ND DN40SDND52 Making it inject into open air on injection pump tester Injection pipes 60X1 6 X600 Injection pressure 120 kg cm Delivery pressure 2 0 Test oil JIS No 2 gas oil Running injection pump at 600 r p m Main spring Angleich torque spring 91 i Limit of Section TETE Checkup Items m ge LA earance Angles Fuel system Er Blectric system RE Strength of springs 0 5kg 15 aa e Terminal Non load be low 2 100 Maracteristia oa SE Ho 113 Performance Load below 2 600 characteristics 14V rpm Motoring test heal 7 8 54 eem Re D pale atm 3 sve ev voltage relay 419 Non load voltage 14 5 155V at 3000 rpm regulation of generator speed Becentricity rancat rese hano 2 20 Axial plar mess rmature Savying of pulley of pulley serie of ier Less than0 LI 5 Diameter Oo Commutaer Eccentricity runout lt Height Brushes Sfrength of springs 92 Conditions Check visually as follows 1 Injection pumpi 04290 52700 1 Anything wrong with 2 Nozzle opening pressure springs 120 kg cm 2 Weight holder pins not 3 I
4. level is up to the mark line cut on the gauge 1 Filter element 3 Head 2 Cover Fig 3 3 Replacing oil filter element Fig 3 4a Lubrication of fuel injection pump pneumatic governor Fig 3 4b Lubrication of fuel injection pump mechanical governor 12 Change of oil Every 250Hr of run screw off drain plug 2 to drain off oil thinned with fuel and pour in about 70cc of new engine oil through level gauge hole Oil in pump cam case usually get thin with fuel that leaks from around plungers and consequential rise of its level raakes it overflow pipe Long operation on oil thinned almost equal in viscosity to fuel will do damage to cam surfaces and bearings 3 Governor pneumatic Every 250Hr of run apply 3 to 5 drops of diaphragm oil through diaphragm oil hole 3 Never use engine oil 4 Governor mechanical In mechanical governor fuel injection pump and governor is forced lubrication by engine oil so it need not check up of oil level 5 Air cleaner with oil bath type Check up of oil level Keep to the optimum oil level in the oil bath Every 60Hr check up of oil level if necessary refill up to OIL LEVEL Lower level oil is not suf ficient clean action and higher level oil act bad influence to engine Standard Fig 3 5 Change of oil in the Change of oil oil bath type air cleaner Every 120Hr change the oil But in the very dusty areas change the oil every day 5
5. 2 Connect earth terminal firmly with frame or with terminal E on generator Its loose connection wil much affect relay performance causing too much current to run 3 Relay bears a seal placed on after necessary adjustments Its checkup and adjustments require precise instruments 1f gone wrong have it serviced at a specialized service shop without breaking the seal 6 2 2 A C Generator Relay Relay The relay is a pointaction type that regulates the field current by closing and opening the contact points so as to control the generator output 6 3 Starter The starter is a D C compound motor of so called pinion shift type where pinion is shifted by magnet switch It is provided with an overrunning switch so as to prevent it from driving the starter any longer than necessary But remember that its function consisting only in starting it should be switched off as soon as the engine catches 1 Keep flange fastened tight Poor grounding will keep starter from running 2 If starting should be difficult don t run starter repeatedly but take appropriate measures and after pre heating well try again 3 Ifa press on button S on starting switch has failed to bring pinion in mesh to set the engine running switch off starter immediately If it should be kept on with pinion out of mesh or in imperfect mesh magnet switch might get burnt 4 With long use commutator will get blackened or spotted with burns and thus spark harder So
6. Centrifugal force of flyweight weak force of control spring and spring force of start spring act each other and keep the smooth idling by this force balance As engine speed rise centrifugal force of flyweight becomes large and push the control spring and floating lever moves to the right hand and transfer the control rack to the fuel feed decrease As engine speed becomes to fall it acts the opposite action of above and keep the constant idling by this action and reaction Fig 3 30 shows the situation of max engine speed control Stop lever ga rack Max ed T Fuil hd Adjusting lever tart Stop Start spring de miir Floating lever Supporting point B Supporting lever Ed 2 Stopper Supporting point A Fig 3 30 RUV governor movement of max engine speed control When the engine speed rise from regulation speed by the rapid down of load while the engine running centrifugal force of flyweight overcome the spring force of control spring and flyweights expand to the outside and move the governor sleeve to the right hand as illustrated arrow mark At this time supporting point B of floating lever which contact to the governor sleeve move to the right hand as A is supporting point Therefore it moves control rack to the fuel feed decrease and acts not to over the regulation max speed In any case whatever don t tamper with the seals on Fig 3 31 33 Injection pump full load s
7. HE gx Guidedever HE E Tension lever ds Shifter amp Guide bush Ful load stopper Fig 5 Idling The flyweight transfers the guide bush and the shifter following the direction of the arrow as shown in Fig 5 The guide lever connected with the shifter will move with the shifter and revolve the floating lever and the lever will pull the control rack connected with it to the idling position In this case the tension lever comes in touch with the idling sub spring and performes idling smoothly helped by the spring When the r p m is lowered the centrifugal force will be decreased the spring will be eased so as to move the shifter and the guide bush and the control rack will be also moved toward the full load In case when the r p m is extremely lowered the weak start spring will also begin to act to pull the control rack swiftly toward the full load and the specified r p m may be maintained 3 Controlling process at the highest rotation Fig 6 In case when the engine at a certain r p m fixed by the control lever is affected by load or remains non load the governor excepting the case of over load will maintain the adjustment of rotation within the limit which is fixed by the changing rate Let it be supposed that a driver moves the control lever from the idling position to a position where the proper speed will be obtained through the link by working the pedals Fig 6 in thi
8. 284 15 oso Valve guides Pitting depth Height 0 3 and holes above head top surface 3 Ep Waves Valve depression 0 2 Valve seats and outer _ Inlet 8 055 0 085 0 15 am diams and Stand Exhaust 0 070 0 099 0 20 Margin Margin 54 Valve face reface 1 404 5 82 Limit of Use gt a ang Crank shaft pin 0 25 Decrease of margin by refacing up to 1 2 1 According to Cols 8 and 11 use oversize rings Oversizes 0 25 0 50 and 0 75 2 Replance oil rings in sets If sample not available with expander springs measure approximately at top of cylinder place piston pin DEER TI TI epe respective pairs 2 In putting together each HIPH en same side Till worn up to limit of repair replace metals one limit over use undersizes metals Undersize 0 25 0 50 and 0 75 re grind Crank shaft pins unde size 0 25 0 50 0 75 1 Use crankcases and bearing caps in a set 2 Place metal with thrust bearing at top 3 Of each pair of metals place that which has oil hole won the other ind journals Ungersize ERREEN Till worn up to limit of repair replace metals once limit over use undersize metals Undersize 0 25 0 50 and 0 75 Belsrs enin peri ne Gri th Repair bend or replace umma OO If over limit of repair replace 1 3 pecia tools available to guides
9. Check electrolyte level O Usuall sally Once in and refill E two weeks but Battery once a week in Measure specific gravity Summer of electrolyte See Clamping eee e I e e 9 Notes General In very dusty areas First servicing for new engine or after overhauling Services to be made by your dealer or a service shop CHAPTER 4 TROUBLE SHOCTING When the engine has got out of order or something wrong happened with it consult the following instructions to take appropriate measures In the event of any serious trouble such as arisen in the inside of the engine or with fuel injection pump ask your dealer or a service shop for necessary repairs Whenever any trouble noticed put on record its detailed descriptions and the odometer reading on that day In disassembling to research into the cause of trouble and repairs take necessary measures to keep off dust and arrange removed parts so as not to miss any of them as well as to permit easy reassembling 59 1 TROUBLE SHOOTING CHART fficiently to crank engine motor does not Engine can be A little exhaust Too exhaust smoke Starting turn over su cranked manually Engine cannot be cranked manually Heater plugs do not glow red Heater plugs glow red too early Too much white exhaust Engine knocks excessively Engine is noisy Improper fuel supply to injection pump Greater variance of inje
10. EP tt Tension lever Fig 11 In a governor with a stop device control lever may be transferred to STOP by moving the stop lever to STOP regardless of the positions of the flyweight and other lever mechanisms Fig 12 By means of the two stoppage system the engine will be stopped without jet fuel 44 STOP Shs E loati ng lever Control rack ENS D y Ri Guide lever Governor s pring i Swivel lever Shifter amp Guide bush Stop lever Fig 12 4 8 Automatic timer To the front end of injection pump is attached an automatic timer or a device that changes the phase of the pump camshaft with its driving shaft according to fluctuation of the engine speed so as to provide the fittest injection timing The design is such that automatically puts ahead the injection timing with a rise of the engine speed and regards the injection with its drop Fig 3 32 shows the timer in disassembled condition Each of two flyweights has a hole by which it is supported on flyweight holder On it is made a curved surface designed to help it develop the required efficiency Bearing pins fixed on the holder have one of the seats for timer springs FLYWEIGHT LEG ca CASE BEARING PIN ROUND NUT OIL SEALS ij CURVED 50 FLYWEIGHT HOLDER TIMER SPRING CUIDE CAP FLANGE ADJUSTING WASHER WELDED IN ONE BODY O RING Fig 3 32 Automatic timer In appearance the flange looks identical to that
11. Swe Ges RU 10 4 1 Required quality 10 4 2 Handling of cooling system 10 CHAPTER 3 REGULAR 11 1 Lubrication 2 0 lecce hh hh hat 11 2 Airsyste jab he SE BE u a ma EN ec dv n RUE ee 15 2 1 Air cleaner bath type 15 2 2 Air cleaner filter paper type ute du atte Seton c rid 16 2 3 Valve clearances 18 2 4 Compression pressure 18 Rerum Ruler aene e TR e 18 29 1 Oilpan lon ue er gr rne een feu beer dra adn ie tn 19 2 Oilfilter sic eee hs we eld ol ed x eas qus 20 3 3 Differential bypass valve 20 34 Qil pressure 2 7 isea a E A E T gee aie 21 system msa meae a aa ee a wa E etna hand Soe 22 4 1 Fuel Filter c g css Sper see eters ole end as dies nth a tere RR le eee ae 22 42 Bleeding priming 24 4S3 Checkup of nozzles i ccc bo been we eh Ses 24 4 4 Fuelinjection pump donus eaten secs saa ets 26 4 5 Fuel injection timing 27 4 6 Governor pneumatic 28 4 7 Governor mechanical
12. axe x BREEAM RT RERO SES 77 DECUIT Tr 77 11 Water pump ilf yw Rb y eden dre ee ane bite E eye rre eR v 78 12 Bolt screwing 2 yen md hmm oy ee Pr a eh ae arae 78 Model 40050 engine service standard 80 HAPTER TOOLS Reda ino ann E SU ale a e s 100 T Commori tools 2 2 cere m RA eae ees ARR ec se pP V a eoe dI Pie 100 2 Specialt ols gt ER phar e mera Uy Ve Rer IR a ee tans YEA RUE oe 101 4APTER 7 MAIN SPECIFICATIONS AND PERFORMANCE 103 1 Main specifications of Mitsubishi Diesel Engine Model 40050 103 2 Performance of Mitsubishi Diesel Engine Model 40050 104 4DQ50A for motor vehicles performance curve 105 4DQ50C for construction machine performance curve 106 4DQ50P for general power performance curve 107 1 PREFACE In every new Mode 4DQ50 Engine fuel injection pump and governor lever bear lead seals that were put after their setting upon final confirmation of its performance through test runs at our factory This service manual is intended to cover regular maintenance services For informations about particular servicing especially of sealed units and parts Such as mentioned above please contact our service man or your dealer Engine name plate is found on the up side of rocker case Engine Model and No are given on it They are aiso stamped on the
13. engine emits then much black smoke through air cleaner making noise at the same time But it will rather hard to stop in the usual way for exhaust pressure will then press governor diaphragm so tight to full injection position as not to permit stop lever be easily pulled back So take any of the following emergency measures to stop it 1 Bring accelerator button to full open position and force back stop lever 2 Increase load to maximum to bring the engine to stop Apply brakes if available 3 Shut exhaust pipe by hand or with waste cloth Keep in mind that long reverse running will make oi pump run reverse too and as the result metals will get burnt from the stop of circulation 6 8 HANDLING IN COLD WEATHER When the air temperature is very low and the engine is cold engine starting is confronted with such factors as low temperature of intake air which disturbs the rise of compression temperature an increase of oil viscosity and a drop battery voltage which keeps starter from developing enough power to drive the engine in addition cooling water and battery electrolyte may freeze up For starting and handling in cold weather follow the special instructions given below amp 1 Starting in cold weather Proceed according to the following additional hints so that a single attempt will make success in starting Repeated use of starter will discharge batteries 1 2 3 4 Pu
14. in forced circulation by centrifugal water pump The system has a thermostat whose valve remains close at low water temperature letting cooling water circulate between water pump and engine body via bypass hose and opens as water gets hot from absorbing heat from crankcase cylinder head etc to let it run into radiator to be cooled there by air blasts from fan and at the same time close bypass hose Thermostat case on cylinder head has two bosses one covering hole to fit in thermostat and the other water outlet for car heater 5 1 Cooling water and radiator 1 For checkup of water level refer to Checkup and preparations prior to starting 2 In order to remove scale and dust in radiator and engine water jacket to improve cooling efficiency open drain cocks to drain fil radiator with fresh oil through its iniet and run the engine for some 20 minutes for flushing at intervals of 500Hr or 12 000km of run or twice a year in spring and fall If they have gathered much scale and dust run the engine for about 30 minutes with caustic soda solution or cleansing liquid in the system and drain it off then fill the system with fresh water and run the engine again for flushing Before and after the use of an antifreeze be sure to flush radiator 3 For engine that has rather intricate water piping for the equipment with oil cooler or for other reason open bleeding cocks on cooling system each time cooling water changed to make sur
15. its bot tom is outlet Be careful not to con nect wrong pipes with them Refer to Fuel system diagram in inlet joint of fuel feed pump that connect pipe from fuel tank is placed a strainer to filter off large dust particles Clean it every 120Hr of run If choked with dirt fuel feed will go down Filter cover Gasket Element Spring Filter case Bolt Drain plug Bolt Air plug Element 3 a Spring N with spring seat Y Drain plug Fig 3 15 Fuel filter 4 2 Bleeding or priming If air should get in fuel system injection will go wrong keeping the engine from steady running or making it difficult to start So whenever any servicing done with this system bleed or prime it in the following procedure 1 Loosen bleeding plug on fuel filter and move hand pump on fuel feed pump up and down As fuel filter is fed full with fuel air bubbles will run out with fuel through bleeding plug When the outflow of fuel does not contain air bubbles any longer screw bleeding plug tight 2 Loosen bleeding plug on the top of injection pump and move hand pump like wise up and down to eliminate air out of fuel pump in it 3 With nozzle side cap nuts on injection pipes loosened and stop lever in full open position run run the engine scores of revolutions by starting motor and all four injection pipes will be bled of air at a time The bleeding must be done too when the engine has be
16. or broken delivery valve springs Governor stop lever link is binding Control rack is sticky Jammed plungers Jammed tappets Worn plungers Worn tappet cams Worn bearings Loose plunger pinions Improper full load setting of governor Open the cock Fill fuel tank Repair or clean fuel pipes with air Retighten attaching parts or replace fuel pipes Remove and clean stainer Repair Retighten connections Disassemble and clean filter Bleed air out of fuel system Replace plungers Replace tappets Replace plungers Replace tappet cams Replace bearings Replace plunger springs Reinstall properly by matching stamped marks Replace valves Replace valve spring Repair link properly placing lever in neutral position Relubricate or repair Replace plungers Replace tappets Replace plungers Replace tappet cams Replace bearings Reinstall properly by matching stamped marks Adjust governor setting on bench Excessive injection quantity Improper fuel spray from injection nozzles Injection timing too advanced Injection timing to retarded Poor grade of fuel oil Low oil pressure Stop lever jammed in increase position Improper full load setting of governor Loose plunger pinions Sticking needle valve s in one or more nozzles Damaged nozzle tip seats Worn or broken nozzle springs Extremely low injection pressure Carbon deposited on packings at nozzle tips
17. ufficentiy e Retighten and replace gasket if necessary Replace crankcase Check for connections and repair If necessary replace part s Repair and replace if necessary motor if ne Repair or replace ning gear Recharge or replace battery If necessary heat it Replace part s Replace copper packing s and if necessary heater plugs If necessary replace charging generator Connect wires properly Repair and replace if necessary Repair and replace starting cesary Replace pinion Adjust and replace if necessary 63 e Repair and replace if necessary Repair and replace if necessary Check and replace bearing with undersize one ne s if necessary Retighten Re time timing train or adjust valve P D d properly Replace part s Adjust valve clearance to 0 3 mm Repair Replace geat s or idler bushing 5 2 TROUBLE SHOOTING CHART APPENDIX Improper fuel supply to fuel injection pump Greater variance of injection quantity Insufficient injection quantity Closed fuel tank supply cock No fuel in tank Clogged fuel lines Air in fuel system Clogged fuel feed pump inlet strainer Defective fuel feed pump Leak in fuel lines or connections Clogged fuel filter Air in fuel system Jammed piungers Jammed tappets Worn plungers Worn tappet cams Worn bearings Worn or broken plunger springs Loose plunger pinions Defective delivery valves Worn
18. 10Hr At the same time clean the oil bath quantities of oil is 0 85 titres and element 6 Starter Every 1 000Hr of run apply to pinion shaft bearing in clutch housing through respective oil holes 1 Fig 3 6 To apply oil to starter 7 Tension pulley Fig 3 7 To apply grease to tension pulley If engine is no need of dynamo tension pulley is equipped Tension pulley has a grease nipple Fig 3 7 every 250Hr of run apply grease to it Lubrication Table for Model 4DQ50 Engine D ti Lubri Lub intervals ems escription ip cants Daily conr 120Hr 2509 500Hr x Ep fena teet o E ee the same Engine oil pan Refer time empty Change oil oil filter and replace filter elements as Check devel oil level ae eo ee a ee 3 Change ot o Apply to 3 5 Pneumatic diaphragm Pam Air cleaner Check oil level ei Em Se change i Spee Apply oil to Several h Apply oil to me eis id Note 1 Marks D Generally O in very dusty areas x First service for new or overhauled engine 2 Symbois EO Engine oil 0 0 Diaphragm oil 3 Mechanica governor is forced lubrication by engine oil 2 AIR SYSTEM 2 1 Air cleaner oil bath type Model 4DQ50 engine is equipped with either of oil bath or filter paper type air cleaner Oil bath type air cleaner consists of centrifugal type pre clea
19. ECIAL TOOLS For overhauling the following special tools are available on request 30691 00300 Socket wrench Camshaft thrust plate attaching bolt i and installation M 30691 11109 ee a eee DENN Compression pressure measurement measurement Bub a a ee ENE CEE NENNT MENELCIINN T 1 en a XR D 0 eee MEN me i mter La ces Wesce 3 Wi in WEE E NEL I BOB with 8 31391 10600 Bn uus ee Cu a ee 1 an vantro s a Adapter Camshaft bushing removal and instal lation 30891 04600 Camshaft bushing removal and instal lation NEM v MEE _ ae eg TT TU Gam 1 at cen x xeimam i a 101 CHAPTER 7 MAIN SPECIFICATIONS AND PERFORMANCE Model Uses Type Cylinder No arrangement Cylinder bore x stroke Piston displacement Compression ratio Firing order Direction of revolution Fuel Engine oil Lubrication system Oil pump Oil filter Cooling system Water pump Thermostat Fuel system Fuel injection pump Fuel injection nozzles Governor Autotimer option Fuel filter Air cleaner Electric system Starter Glow plugs 1 MAIN SPECIFICATIONS 4DQ50 For motor vehicles construction machine general power etc 4 cycle water cooled swirl chamber type Diesel 4 in line 84mm x 94mm 2 084cc 127 cu in 21 1 1 3 4 2 Clockwise as seen from timing g
20. Improper installation of fuel Injection pump Incorrect installation of timing gears Improper installation of fuel injection pump Incorrect meshing of timing gears Worn cams tappets or bearings of fuel injection pump Poor grade of fuel oil Water in fuel Lack of oil in oil pan Air in oil strainer 65 Possible remedy Repair lever link properly placing lever in neutral position Adjust governor setting on bench Reinstall properly by matching stamped marks Repair and replace nozzles if necessary Repair and replace seats if necessary Replace nozzle springs Adjust Pressure to 120 Skg cm 1706 4 71 1 1b in on nozzle tester by inserting shim s Remove carbon Re time properly by tilting injection pump toward engine Re time timing gear train Re time properly by tilting injection pump outward Re time timing gear train Replace Use good quality fuel Use good quality fuel Add oil to prescribed level Replace damaged pipes or packings Retighten loose parts Pumping up of oil Poor compression Defective oil pump Clogged fuel lines Defective oil pressure valve Clogged oil filter Leak in lubricating system Excessive oil in oil pan Worn cylinders pistons or piston rings Sticking piston rings Worn valve guides Prolonged operation under no load Clogged air cleaner paper element type Clogged air cleaner Oil bath type Clogged intake
21. SERVICE MANUAL E MITSUBISHI DIESEL ENGINE 4DQS0 ate MITSUBISHI INDUSTRIES LTD MITSUBISHI DIESEL ENGINE MODEL 4DO50W CONTENTS PREFACE eel red iR E E oy Gime E RR RR P9 ens 1 CHAPTER 1 OPERATION AND HANDLING 2 T Newengine 22s e EUR RR quw we vm eie REUS A RC ee eels 2 2 Checkup and preparations prior to starting 2 3 Enginestar ng Rex exor Ree S DERE PES 4 4 1 5 5 Engine operation 3 5 le v e ERR es Sete Sis RU IR e E a seh EE 5 6 During Operation i e RR re S IRE TI UR gee 5 7 Stopping ess ene e ERE RE ER RU RE ERAN SEN IE E 6 8 Handling in cold weather 7 81 Starting in cold weather 7 8 2 General instructions 7 9 Handling the hot season 8 CHAPTER 2 FUEL OIL AND COOLING WATER 9 NEU NE ER ROT MEC es 9 2 Engine Oll egere eme opui S or a RC Bae RUNE 9 2 1 Quality required of engine oil 9 2 2 Recommendable classes of engine oil 9 23 Time to change engine oil 10 3 Diaphr gm oil soas cia ade e mu RR I E E ALa 10 4 Cooling water secos ue me S eee
22. ad center and holding it there mesh gears one after another with idler following their numerical meshing marks as illustrated in Fig 5 10 Align autotimer key way with mark line on injection pump gear 6 2 Valve timing To install gears according as indicated with numerical meshing marks dispenses with the trouble of checking valve timing For reference sake however valve timing diagram is given in Fig 5 11 Every cam having a symmetrical profile checkup of valve timing requires to measure crank angle at max cam lift to see if it equal to the angle indicated with broken line in Fig 5 11 The procedure is detailed as follows r Take for instance No 1 cylinder inlet and exhaust valves First set valve clearances by means of plane plates with uniform thickness of 3 4mm and put the thinnest Exhaust cam uf cam max li max lift approx 3 4 for measurement Thickness of plates used Valve Lift A NI U Crank Angle Fig 5 11 Valve timing 0 05mm of thickness gauge blades between valve tops and rockers Now turn crank shaft slowly until gauge blades are pressed tight this point crank angle is valve lifts reach point A and B shown as Fig 5 11 The mid point between them corresponds to max cam lift Compare the results of measurement with the specified crank angles 7 OIL SEALS Oil seals on front and rear ends of crank shaft must be centered right So take care in clam
23. adiator 3 Generator charge While generator is charging batteries ammeter pointer indicates scale At the beginning of charging it indicates about 10A then gradually decreases as batteries get charged So you must not take this aspect for any generator trouble Charge pilot lamp which is attached at option goes out when the engine has started and generator begins to charge If a rise of engine speed should not put it off check and service charging system immediately 1f the system left defective batteries will entirely run down making engine starting absolutely impossible 7 STOPPING After the operations over let the engine idling for some 5 minutes Don t bring it to a sudden stop with its parts heated hot As letting it idling pull back stop lever to position stop and fuel injection will be cut off and thethe engine come to a stop When the engine has come to a dead stop pull back stop lever to neutral Remember that if the lever released when the engine has not yet stopped it may run reverse Note Reverse running of the engine Model 40050 engine may happen though rarely to run reverse in the following cases 1 When in an attempt to cut off injection by pulling back stop lever the lever is released before the engine comes to a dead stop 2 When starting motor is switched on with batteries not charged enough to power it as required to start the engine Reverse running can be readily noticed as the
24. al both inlet and eai yanes measured in warm engine if Engine is uniform temper Adjust If not over limit of repair replace tappets In setting give even play in rocker shaft direction If over limit of repair replace bushes ream if necessary Replace thrust plates to z Gh 7D 776 84 Replace bush Replace thrust plate Replace gears sur ace Replace case E 5 en 4 o t o o 3 o o t o eo Replace gear ass y 85 Set tin nat Epp e acai ele ane mena system Qil filter bypas mene ler Unit seals Valve open 76 5 C 2 C Thermostat a Pal ERES eratu e Valve Hitt fomm Water pump Oooling system Resistance 250mm q negative or higher at 3 000 Air cleaner pressure r p fn filter paper type Air system 65 Axial play of shaft 86 Varies 0 24 2 1 __ Sarit per 1mm of po NR ies 0 1 5kg cm 1 Ero m thicken ae or If hitting replace impeller and bearing 23 5 Replace unit seal ass y Usually press with a finger Shifting generator adjust with adjust ing plate Clean or replace element Negative pressure 4 take off po Adjust with shims Coat with metal cement 87 Hc peu E qi m Injection starti z CCELI TE E N Spray angle main
25. alve is full open 4 Standard compression pressure is above 20kg cm at an engine speed of 1507 200 r p m and with oil and water tempera Fig 3 10 Adjusting valve clearance tures in a range of 20 30 C Please have it measured by your dealer or at a service shop 3 OIL SYSTEM As can be seen in circulation diagram Fig 3 11 lubrication system is forced lubrication by a trochoid oil pump At option a water cooled oil cooler is equipped between oil pump and oil filter to keep oil in an optimum temperature range 3 1 Oil pan 1 For checkup of oil level and change of oil refer to Sect 1 Lubrication 2 Every 500Hr of run unfasten oil pan to wash its interior and oil strainer in cleansing oil Rocker 74 lt 9 1 i Rocker shaft Oil jet to gears Oil filter SEM VON Oil level gauge N peg Oil strainer 1 Piston 2 01 Filter 3 Oil jet 4 Crank Shaft 5 Oil Strainer 6 Rocker arm 7 Rocker shaft 8 Oil alarm 11 Water pump 9 Oil pump 10 Injection pump Fig 3 11 Oil circulation diagram 3 2 Oil filter Oil filter is of the filter paper full flow type 1 Every 250Hr run change oil Ori the same occasion unfasten filter case and replace element with new one If bypass alarm lamp has got alight with the engine hot replace element as soon as possible without sticking to the standard intervals 2 At the same time to replace element wa
26. an belt 2 Generator pulley 3 Water and a consequential drop of pump 4 Adjusting plate 5 Lock bolt cooling efficiency will cause Fig 3 36 Checking the tension of fan belt an overheat Continuous slipping does it damage too 2 Inspect fan belt at times to see it is not damaged Keep it always free from oil grease and dirt 6 ELECTRIC SYSTEM 40 mo 5 md Qg5med STARTER IZV 2KW BATTERY 12 100AH Fig 3 37 Diagram of electric wiring in case of AC dynamo ON S Fig 3 38 Diagram of electric wiring in case of DC dynamo BATTERY SWITCH EIERTER 24V 2KW BATTERY 127 i00AH 2 Ea Fig 3 39 Diagram of electric wiring 24 system The wiring diagrams given herein cover only the engine System is of the so called negativeearth type and standard specification is 12 volts and wiring diagram shows Fig 3 37 in case of A C Dynamo and Fig 3 38 in case of D C Dynamo 24 volts Fig 3 39 is special specification In this case 40050 Engine is equipped with tension pulley in stead of Dynamo To follow the service hints given herein in addition to those in lubrication Table will maintain the electric system trouble free Prior to making any service be sure to turn off battery switch 6 1 D C Generator This generator is a D C shung wound type whose main components are field coil armature and brushes 1 2 Brush Ball bearing Check for wrong wiring and loose te
27. and change of oil refer to Sect 1 Lubrication Mechanical governor is forced lubrication by engine oil so it need not check up of oil level and change of oil Being precision machined and adjusted like nozzles injection pump will not require any particular adjustment but at the time of over hauling it should be thoroughly adjusted by means of a pump tester If anything unusual noticed with it have it examined and if necessary serviced by your dealer or at a service shop In such a case that nozzles having nothing wrong at all combustion does not go well in any of cylinders check as follows a With the engine running loosen either cap nut on one injection pipe after another So you will fined the cylinder from which the symptom comes Such symptons come from for example the following causes b Set screw on pinion is loose In this case injection rate is out of perfect control that is to say not varying exactly in conformity to control rack travel c Plunger spring is broken d Delivery valve spring is broken To inspect it loosen delivery valve spring Broken spring keeps injection from breaking clean off for poor sucking back of fuel Inspect the contact of delivery valve seat too If badly worn or otherwise defective pull it out to replace by means of a special tool intended for that In putting together again attach anew gasket to valve so far as possible In these operations take every possible measure to keep o
28. c tion quantity Defective fuel injection pump insufficient injection quantity Excessive injection quantity Improper fuel spray from injection nozzles Excessive fuel return from injection nozzles bi abc timing too vanced Injection timing too retarded Defective automatic timer Engine speed too low Failure of engine to stop properly Poor grade of fuel oil Fuel oil viscosity too high Poor grade of oil Oil viscosity too high Oil viscosity too low low oil pressure Excessive oil leak Pumping up of oil Clogged oil filter Defective oil indicator switch or lamp Lubricating system e ree pre 9 9 9 1 9 o Dara I Prep fords 5 Engine turns over reverse When engine stops warning lamp does not come on Worning lamp comes on at low speed operation Warning lamp comes on at high speed operation Water temperature too high Engine overheats Water temperature too low Indicator lamp does not BEIDENSESEEERWERELLLAUT stops i Bag Indicator lamp comes i 1 1 1 onat high speed operation 2 jJ e UID fa BM 1 3 i PTS ag es if d d ak iita BE n 8 i Y ER P amp gt o gi E t 1 i p aq uOnULoJUI JO e Engi
29. cket nuts Engine mounting bolts Exhaust manifold outlet nuts Regular checkup and Table for Model 4DQ50 Engine Consult Lubrication Table too Units amp Part Checkup amp Service intervals n arts ore Daily 120Hr 250Hr 500Hr1000Hr ure imo fot i bath Disassemble and clean element z is tee Clean case and element case and element Cean case and element CO type Replace element tts 0 25mm in cold engine both for inlet and exhaust valves Valve clearance check and adjust Compression pressure measure the poA time to Replace element ange oil or when il fi ypass alarm lamp Oil filter uem ss Wash inside of inside of case Lx Tet Drain off water and Fuel filter sediment Replace elment element jo pe feed 78 58 ans i i ni DOBLES Check injection pressure 2 Injection and spray _ _ nozzles Remove carbon from nozzle seat packings Check fuel tevel and C refill Fuel tank Drain off water and sediment 6 1 Before and after eee 57 Fuel System Cooling System secs mw sow zowfpsowponsdooos _ n Check brushes replace ct if necessary Service commutator commutator Check brushes and Check brushes and commutator Starter Dismount to check pinion clutch
30. ction Running injection pump at 150 r p m see how much time required for feed pump to start discharging Ditto left Measure at full discharge with injection pump running at 600 m Punaing at 58 0 2 Replace cam shaft 0 25 Adjust with shims Overall play less Replace tappet complete than 0 3 0 075 89 serene Limit of pee ee Fuel System Oil t Oil tightness Collar width Control sieeve groove 0 02 with and standard 0 078 clearance 1 _ 9 _ Springs a Play of pinion ov raer os At standstill Sliding resistance Oil tightness Delivery valves Spring free mee Injection starting 50 intervals Lift to start injectio 0 05 with rack at 21mm position Diaphragm Drop from 500 to 480mmAq not ee ae Main spring Spring constant VII UT Thickness of shims A EN Thickness of shims B ae Fuel injection pump governor Spring data Pneumatic 90 Limit of Use not below 150kg cmn Use good delivery valve Put a pressure gauge of 300 400kg cm set rack at small injection 0 15 rate and running pump at 200 I p m read the gauge A reading above 150kg cm is 0 1 satisfactory 0 5 0 25 Use good plunger Set pressure at 150kg cm and bring control rack to non injection position
31. d connecting rods always with good care not to scratch or otherwise damage their bearing surfaces In assembling them clean bearing surfaces and coat them with oil then clamp them down making sure that they are free from any strain 5 2 How to assemble main bearing metals Of each pair of main bearing metals assemble that which has a groove in the middle that is on crankcase up side especially the other with thrust bearing on the side of timing gear case To prevent leak of oil give a thin coating of liquid packing to their contact surfaces with main bearing cap cases on both ends For connecting rod bearings either of the pair can be assembled upon the other 5 3 Undersizes To both main bearings and connecting rod bearings metals must be renewed when their clearances exceeded 0 2mm When replacement of metals not considered to produce satisfactory results because of crank shaft being unevenly worn or streaked deep grind it so much as to fit to any of undersize metals which are available in three sizes 0 25 0 50 and 0 75 TIMING GEAR 6 1 Timing gear train injection pump gear W 38 teeth Crank shaft gear Autotimer jet W 19 teeth W 43 teeth not provided but for autotimer plug if sutotimer jet provided 22 Fig 5 10 Timing gear train The view of timing gear train with cover off is shown as Fig 5 10 To install gears that were taken apart bring 1 cylinder piston to top de
32. d of commutation The construction of the A C generator is illustrated in Fig 3 42 Revolution of the field generates a three phse alternating current in the armature which is rectified by silicon diodes installed in the rear bracket and supplied at D terminal The field circuit is electrified at F terminal from the battery through field relay and relay the current running on one part from brush to the field coil through slip ring and on the other to E terminal through the other brush and slip ring Having silicon diodes the generator cannot make self starting as a D C unit does by residual magnetism of the field coil so is excited to start from the battery 59 The alternator is designed to limit its own output by itself so that the amature is free from any overcurrent that may burn it up It is free from an overcurrent too because the silicon diodes check any current from the battery when the output voltage of the generator falls below the battery voltage To operate the field relay the alternator has N terminal connected with the neutral point of the armature A half of D terminal voltage is on this terminal Relay 6 2 1 D C Generator Relay This unit performs the functions to regulate voltage generated by generator constant voitage regulation and to prevent reverse current to generator 1 Make sure that relay terminals A and F are connected with right ones on generator Wrong connection will cause relay to burn up
33. d right to the values and firmly fixed at our factory the injection starting timing will never to wrong i H g 1 sa a ADEE E ywheel Fig 3 21 Timing mark on crank shaft pulley In the case that the injection starting angle needs to be newly set for such reasons as replacement of the injection pump with a new unit do as follows 1 First locate the top dead center of 1 cylinder compression stroke turning crank shaft For this turn crank jaw with a wrench if it permits easy access of hand or 4 ring gear by a tooth after another Fig 3 23 Timing mark on with a screw driver if it does not injection pump Go on turning it until symbol T on crank shaft pulley or symbol 1 4 on flywheel exactly meets the pointer and 1 cylinder piston will be at top dead center But assuring this open rocker case cover and make sure that both 1 cylinder inlet and exhaust valves keep proper clearance 2 With 1 cylinder piston thus placed at top dead center read at what crank angle injection will start For this take the following steps 3 Loosen off 1 cylinder injection pipe so that a little fuel remains in the upper part of delivery valve holder Slowly turn crank shaft in its usual direction that is clockwise as viewed from fan and fuel level will start swelling Read crank angle at that moment 4 in case injection timing needs to be set ahead move injection pump body little by little in the rev
34. e tension of the governor spring the tension lever is pushed back The shifter the guide lever and the control rack move in the direction of STOP and obtain a new balance at the place where small jet volume suitable to the load condition of engine may be obtained 4 Work of Ungleich The fuel supplying curve is shown in Fig 10 In this figure the fuel which will burn smokelessly smoke limit at the regular r p m and at a fixed load is ploted by inspecting the jet condition against engine cylinder per each stroke adopting the r p m as parameter The Fuel demanding curve Fuel outlet curve o Fuel Jetting volume NI r p m of Engne N2 Fig 10 fuel jetting volume curve in the same figure is shown at the full load position of the control rack by adopting the fuel jet volume which is supplied by the injection pump per each stroke as function This fuel demanding curve shall be made similar to the fuel outlet curve within the limit of possibility In other words the fuel necessary for engine shall be injected smokelessly so as to operate engine without hindrance Fig 10 shows the following facts The demand for engine fuel decreases as the r p m rises worse condition of air inhalation on the other hand the injection pump when the control rack placed on a fixed condition injects more fuel as the r p m rises No engine can burn consume this increased fuel without giving out smoke If the maximum jet
35. e that the piping is full in every part If an overheat noticed even when thermostat is functioning well bleed or eliminate air out of the system 4 If dust collected on fins clean them by blowing compressed air or water on them from fan to recover cooling efficiency Don t try to remove foreign matters with a wire or the like Such a way of cleaning often makes scratches or cuts in water pipes hence leading to leakage 5 2 Thermostat Poor operation of thermostat will much affect the service life of the engine in the long run fn case the engine overheats even when cooling system is full and fan working well the probable cause is that thermostat has got stuck up and remains close If on the contrary long oreration should not raise water temperature up to the optimum level 75 85 C thermostat is suspected to remain open from puncture In either case check it and take necessary measures Thermostat is designed to start opening at 76 and fully open at 90 under atmospheric pressure Continuous operation on cold water wiil quicken wear of cylinder liners and rings 5 3 Tension of fan belt 1 Every 60Hr of run check the tension of fan belt Optimum tension is such that D a press with a thumb at mid point between genera tor pulley and water pump pulley makes it slack about 12mm Execessive tension quickens wear of belt itself and of water pump and generator bearings while lack of tension makes it slip 1 F
36. ear case Gas oil with greater cetane number than 45 Mineral oil heavy duty type Forced lubrication Trochoid pump Full flow type with filter paper element Forced circulation of cooling water Centrifugal pump Wax type Bosch type Model PES4A65B Bosch type Model DN40SD Pneurnatic Bosch type Model EP MZ60A Mechanical Bosch type Model EP RSV250 Mechanical filter paper element Dry type with filter paper element Oil bath type with pre cleaner 12 volt system common 24 volt system option Pinion shift type 12V 2 0 kW Pinion shift type 24V 2 0 kW Sheathed 10 5V 8 3A 22 5V 4 8 Generator D C 12V 200W A C 12V 300W Battery 12V 100Ah 12V 12V 70Ah x 2 24V 2 PERFORMANCE OF 40050 DIESEL ENGINE For electric generator P Rated output kW rpm 50 bh E 1 500 28 8 3 000 60 Rated output DE 22 5 1 500 45 3 000 Rated output HP rpm 36 a 2 200 46 a 3 000 For Locomotive Hr rated output Um 54 5 a 3 600 For water craft pleasure boats Max output HP rpm 62 3 800 For outomobiles A Max output HP rpm 66 a 3 800 The above performances exclude automobile and water craft use are under standard conditions atmospheric pressure 760 mmHg Temperature 20 C Humidity 65 max output is under condition with 760 mmHg pres 15 C temp Performance tests in relation to the above are being carried out in compliance will JIS specifications I
37. ecomes larger than the spring force the flyweight will spread outside When the r p m decreases the centrifugal foece will decrease and consequently the controlling power of the governor spring will become stronger so that if folds itself inside again The action of the flyweight is transmitted to the control rack through the guide bush shifter and link And the control rack when the r p m of engine increases will be moved in the stop direction Then the r p m is limited because the injection pumpsupplies smaller amount of fuel When the r p m of engine decreases the process will be reversed This RSV as an all spread governor controls the rotations of all kinds covering from the idling r p m to the maximum r p m outomatically If the driver or the operator of the machine will adjust once the control lever at the necessary engine r p m by operating pedals or handles then the governor will adjust the r p m automatically Now let us explain the special operating conditions by taking up several cases for example Fig 3 is the performance curve of these operations Stort Control lever FIG 4 position full Control lever posi tion idle Ideling FIG 5 FIG9 Stop FIG 11 amp 12 r p m Speed Fig 3 1 Starting of Engine When the control lever of the governor is removed to the starting position maximum speed stopper by means of the hand lever or pedals through the link the bosses of the swivel lev
38. eeze The service life of new engine much depends upon how it is handled in the initial runs So lubricate and check it with particular care Refer to Lubrication and Service Tables and before it covers 60Hr follow the instructions given below taking care not to overstrain it 1 After starting never apply load immediately without warming it up well by idling 2 Don t run it at high speed 3 Run under some 70 of load at the maximum CHECKUP AND PREPARATIONS PRIOR TO STARTING Prior to starting the day s operations check as 1 Engine oil level Pull out oil level gauge and wipe then put it in and out again to check oil level Oil level must be above mid point between upper FULL line refill up to upper line FULL Oil level difference between these two lines corresponds to approx 1 litre Fig 1 1 Checking oil level After refilling wait for all added oil to run down into oil pan and for oil level to settle before checking it again 2 Cooling water level Optimum water level is 20 30mm below the bottom of water inlet for pressure type radiator and up to overflow pipe for non pressure type one Remarkable decrease of cooling water means leak somewhere hence the necessity to repair immediately 2 In the case of pressure type radiator don t screw off its cap just after the engine stopped lest you should get burnt by outblow of high temperature steam 3 Fuel Check fuel level If fuel tank is equi
39. egular intervals to see if they are working tight enough and if loose screw again accofdingly Apart from this always give attention to those bolts that can be seen from outside Re screwing of main bolts must be done according to the given below clamping Torque List with fit torque wrenches so should be entrusted to your dealer or a service shop Clamping Torque List for Mode 4DQ50 Engine Ciamping Torque Bolted Parts Cylinder head 12P 1 75 Remarks See Par 7 1 below Main Main bearing cass caps 12P 175 amp s ECCE gt Nozzle tip retaining nuts 22P 1 5 Delivery valve holders 18P 1 5 ERICH 7 1 Cylinder head clamp bolts Every 500Hr of run re screw head clamp bolts For this unfasten rocker case cover rocker ass y and intake manifold and screw them to specified clamping torques following the order indicated in Fig 3 43 Remember that it must be placed with apron shaped parts up In clamping screw boits first a little but uni formly then tight according to the illustration Notes 1 Numbers show bolt screwing order 2 Clamping torque 12 0 kg m 86 Ib ft Fig 3 43 Order to screw bolt on cylinder head 7 2 Main Bearing caps and connecting rod caps ach time to wash oil pan and strainer check bolts on main bearing caps and connecting rod caps and if loose screw them tight again 7 3 Others Keep the following bolts and nuts tight Oil pan clamp bolts Engine mounting bra
40. en left idie for a long time fuel pipes replaced or nozzled checked Fig 3 16 Joint on fuel inlet in fuel feed pump Fig 3 17 Bleeding fuel injection pump 4 3 Checkup of nozzles When something unusual notices with exhaust gas or firing check nozzles and service accordingly Regular checking and servicing of them at intervals of 500Hr of run will keep them always in perfect conditions For new engine check them when it has been run for 250Hr Their checkup and servicing should preferably be entrusted to your dealer or a xervice shop 1 Nozzles are checked by means of a nozzle tester Set nozzle on the tester and slowly pressing its hand lever see how it will eject fuel It must make 24 Fig 3 18 Testing nozzle Fig 3 19 Main injection from nozzle 2 3 intermittent injection in fine spray with sharp hisses Spray must not split at the end nor go astray nor dribble See also at what pressure it will start injection It must be within a range of 120t5kg cm Any discrepancy is corrected by changing the total thickness of shims on nozzle spring with nozzle nut off For the calculation of how much shims must be added or removed remember that 0 1mm of thickness corresponds to approx 10kg cm of injection pressure Main injection that takes place when hand lever is pressed hard must form a straight cone of about 40 in spray angle that Injection pressure adjusting shim contains no large f
41. en the engine is very cold pull stop lever at the same in opposite direction to position stop and an increase of injection will make starting easier In this case pull it I back to neutral as soon as first firing Keep starter running until the engine has completely caught to run with a steady rise of speed but never any longer than 30 seconds at a time If starting has failed don t switch on starter again before both starter and engine come to a dead stop and starter cools down While the engine is running don t try to increase injection nor switch on starter Note According to specifications Model 4DQ Engine is equipped with a governor that has a built in automatic device to increase injection In pneumatic governor use prior to starting place stop lever once in position stop and pull I back to neutral to assure a quick increase of injection Particularly attempt 4 the same when the engine has stopped by chance 4 When the engine has perfectly caught bring back Venturi lever or control lever immediately to idling For starting in winter Refer to Cold starting 4 AFTER THE ENGINE S START Keep it idling at medium speed for some 5 minutes for warm up then start driving or operations This will prove very effective in protecting moving parts from wear and in other aspects With the engine idling check as follows 1 Anything unusual with oil pressure Refer to Par 3 4 Oil pr
42. engine speed oil pressure is kept between 3 and 4kg cm by relief valve on oil filter cover The lowest permissible pressure is 2kg cm Model 4DQ50 engine is provided at option with either an oil pressure gauge or an oil pressure alarm switch which puts alarm lamp alight at a drop below 0 5kg cm 1 Under the following conditions oil pressure often goes out of the given range but will usually become normal as the engine is run a When the engine has not yet warmed up i e soon after its starting In this case oil pressure goes above the standard range claiming for its good warm up through low speed idling b When after a warm up the engine is let to idle oil pressure drops low But this means nothing wrong so far as it remains above 0 5kg em 2 Any other drop of oil pressure than incidental to the above case will lead some serious trouble hence the necessity to check as follows and take necessary measures a is oil level high enough It must be above lower mark line on oil level gauge b Anything is wrong with oil pressure gauge and its piping Check also alarm switch and lamp measuring oil pressure with an oil pressure gauge c Any leak in oil line Other probable causes are d Oil pump suction side piping is inhaling air e Bearings worn down f Oil pump worn down g Relief valve covered with dirt 4 FUEL SYSTEM As can be seen in the above diagram fuel is from fuel tank pumped up by fuel feed pum
43. ep skin diaphragm placed in pneumatic governor of fuel injection pump and to keep governor action smooth and sensitive Use always those brands indicated on Lubrication Table and never substitute by engine oil mineral oil 4 COOLING WATER 4 1 Required quality Cooling water must be clean and soft Never use any water that contains salt or is near a mine or a spa because it will scale hard water jacket and corrode cylinder liners along their outer circumference 4 2 Handling of cooling system 1 in leaving the engine idle for many hours especially in cold weather open all drain cocks to thoroughly drain off cooling water 2 When the engine has overheated and has been empty of water never pour cold water in radiator 3 For the use of an antifreeze refer to Sect 8 Handling in Cold Weather Chap 1 CHAPTER 3 REGULAR SERVICING To service your engine regularly is the key to enjoy its ever trouble free and efficient operation and long service To say nothing of usual services before and after the work appropriate measures must be taken if during operation any unusual symptons in sound exhaust colour smell etc should be noticed In this chapter are given in detail the necessary instructions for regular checkup and servicing starting with lubrication along with the constructional descriptions of engine parts Standard intervals are based on the reading of service meter For any checkup and servicing place the eng
44. er which move together with the control lever will be separated from the guide lever and the governor spring which is connected with the tension lever is stretched This governor spring pulls the tension lever to the place of full load stopper Then the shifter and the guide bush act on the left side and the weak start spring will move the floating lever so as to transfer the control rack of the injection pump to the starting point beyond the position of the full load Thus the start of engine will be easily yielded Shifter amp Guide bush Fll lood stopper Fig 4 Start 2 Controlling process at the lowest governing scope of engine Fig 5 Once the engine has started the engine is kept at idling condition by maintaining the control lever at idling position 2 In this case the idling position of the control lever 2 is slightly before the original position 0 Under this condition the governor begins its self governing automatically When the control lever drawn back from the starting position the governor spring is eased so that it reaches barely the vertical position coming about under the revolving center of the tension lever Accordingly the force of the governor spring which acts on the shifter guide bush and flyweight through the tension lever becomes very weak and the flyweight may spread outside even at a low speed r p m Control lever 2052 v A stop fx co 4 PHO m di BEA non NN x
45. erse direction that its camshaft revolves or toward crankcase Note that graduations on pump flange corresponds each to 6 of crank angle 4 6 Governor pneumatic DIARHRAGM AIR PIPE RACK INLET MANIFOLD VENTURI INCREASE OF AIR INLET BUTTERFLY VALVE FULL LOAD STOPPER INLET VALVE NEGATIVE PRESSURE CHAMBER Fig 3 24 Scheme of pneumatic governor 1 A pneumatic governor for governing of its speed consist of diaphragm block in fuel injection pump and of Venturi unit in inlet manifold which are connected together with an air pipe 2 Now following the scheme and diagram of operation principle we will briefly explain how this governor operates When intake air passes through Venturi that closes inlet manifold to some extent its flow velocity rises but at the same time static pressure at that part to be taken through pipe that opens to its flow direction at a right angle falls considerably below the pressure on the area free from the inflow of air generally atmospheric pressure or in short turns into negative This negative pressure rises as can be seen in Fig 3 25 with the rise of engine speed and consequently of flow velocity of intake air Through an air pipe it is conducted into negative pressure chamber in diaphragm block to work on diaphragm The governing force it produces is calculated Venturi negative pressure x Diaphragm area Governing force Differential pressure between both sides of dia
46. ess them out and r BINNEN 25 ET d Equal both inlet and exhaust Put in seat inserts valves Can be measured as How to fit in inserts is described separately If over limit of repair widen valve bore se tapered cutter of 30 33 Setting Hap apf ae Ceci Jb Free length Lf 48 85 DER d 47 6 4 Parallelness of both ends f B eue E BI qr Remennrs Er Paraieeee o a 08 in cold ex ker shaft Inner and outer diams mie ho les Valve springs Valve mechanism Tappets shaf Inner diam 41 546 Denm Hoz ane rs Use Plates as 5 pe 0 05 0 1 12 0 3 Cam shaft Cam profile a 4 Runout of of center with dier b Eum EET deem ao dier frost RL me e Fittin diam diam shirt oute e 8 jeuen Inner diam rot t TE COLLE HEN Case Gear train IR uu IU EM and standard 0 0 15 8 dec beali outer diane 0 100 0 1 gt d standard clearance Gears 55 Clearance to case top 84 Limit of Use 1 5mm in overall length 1 0mm in coil diam 1 5mm in overall length 1 0mm in coil diam 0 10 Di D2 6 84 0 15 1 0 Remedies Remarks If over limit of repair and shims If over limit of repair add o Equ
47. essure Chap 3 Regular Servicing 2 Does the engine make unusual noise 3 15 exhaust colour abnormal 4 Any leak of water fuel or oil 5 ENGINE OPERATION Mode 4DQ50 engine is equipped with a pneumatic governor or a mechanical governor for each use This governor being of the all speed governing type variation of engine speed depends upon how far Venturi unit is opened for in which position control lever is This design is such that at a certain degree of Venturi unit opening or control lever position engine output is automatically governed with changes of load so as to keep engine speed almost constant During operation leave stop lever in neutral pneumatic governer use For details refer to Par 4 6 Governor 6 DURING OPERATION After warm up run apply load on the engine During operation judge how the engine is going from the indications of meters sound exhaust colour and etc 1 Oil pressure Refer to Par 3 4 pressure Oil pressure gauge if the engine is equipped with one must read 3 4kg cm 2kg cm at minimum at usual engine speed and above O 5kg cm in idling If oil pressure alarm lamp attached watch it every now and then If it should get alight check oil system 2 Water temperature Optimum range is 75 85 C Overheating arises from lack of cooling water loose 5 fan belts and poor functioning of thermostat In case the engine gets overcooled put a suitable cover on r
48. every 500Hr of run take off brush cover and check its surface If roughened polish it with sand paper 400 or so and wipe clean with dry cloth Mica pieces in commutator segments should be undercut 0 5 0 8mm below the sliding surfaces of brushes 5 A heavy current runs through starter circuit Check it and if any loose connections detected fasten tight again 6 4 Battery Battery requires good maintenance as it is the Power Source for engine starting and lamps Every 60Hr of run check and service it as follows Even when the engine is out of operation it should be checked once in two weeks or in summer once a week because it its self discharge 1 Screw off plug and check electrolyte level Standard level is about 10mm above pole plate If specific gravity has increased from evaporation of electrolyte and distilled water If electrolyte spilled out of cells which does not involve an increase of its specific gravity add dilute sulphuric acid of 1 280 in specific gravity at 20 C 2 To see how much battery is discharged measure the specific gravity of its electrolyte The following table shows the relation between the degrees of discharge and hydrometer readings at 20 C Degree of Totally 1 2 Completely Discharge discharged oe discharged Hydrometer vm ome 1 1280 1300 300 Reading Specific gravity varies with temperature For the correction of hydrometer reading apply the formula g
49. ff dust Remember that valve holder must be screwed exactly to 3 5kgm of clamping torque with a torque wrench 3 When injection pump needs to be removed for adjustment or servicing try to learn how to set it right again memorizing especially in what relation the match mark on injection pump flange part is to the mark on the flange plate Refer to Fig 3 22 Before it is fixed again never run the engine lest the injection timing should go wrong For removing take the foliwoing steps Loosen clamp bolts that fasten pump flange to engine crankcase with a socket wrench fitted on the end of universal joint Then unfasten cover from timing gear case and separate injection pump gear from pump camshaft To leave the gear in mesh with idler in gear case will make the pump setting much easier don t disjoin autotimer from the gear for easier operation in installment Having removed injection pump put caps on delivery valve holders to keep off dust 4 5 Fuel injection timing In this engine injection pump starts injection at a fixed time whatever the injection rate may be Model 4DQ50 is attached a mechanical autotimer in option which is coupled with injection pump gear varies the injection starting time according as the engine speed changes and thus provides always the fittest injection timing This injection pump is fastened by means of flange so that injection starting time can be varied by changing its setting angle The pump having been adjuste
50. gs gaskets and liquid packings to be used are listed below Materials of Packings we Gaskets eee Cylinder head Copper asbestos Three Bonds No 201 Front plates Rubber asbestos No 2 Timing gear case d No 2 Timing cover d No 2 Oil pan sides Rubber cork No 2 Oil pan ends Rubber Atomosit Oil filters Rubber asbestos Three Bonds No 2 79 Model 4DG 50 Engine Sectiar Units Parts Checkup Items inal Setting Limit of Beer Standard Clearance 5710 higher than Not below rated Max speed rated speed speed 15 nor above it Min speed 700 750r pm Prieuma tic m above 800 650 700rpm Wechan ica OV gt Above 20kg cm Compression pressure 150 2007 n Ake 3 2 Not below General Valve timing crank angle Illustrated on right 7 Injection starti 1 9 crank e high angle a 8 849 0 035 0 0 20 out of round ess than d 015 amp g Taper ess than 0 015 zz T e 5 P sur face 9 Strain E than 0 05 0 2 of pistons H0 55 0 75 110 above cyl inder crank case top surface psi a E 8 0 2 3 M tere 38 0 15 5 re I 2 oil 0 15 0 Inner and outer diams 2 and standard 0 011T 0 0 05 arans Tod difference 4 pi Stans 80 Weight 14 Service Standards Limit of Use Remedies Remarks Check Venturi or gove
51. h standard radiator In winter use engine oil of lower viscosity Refer to Chap 2 Engine Oil Existence of water in fuel will cause some trouble with fuel system from 7 freezing of pipes So bleed or prime fuel tank fuel filter etc 4 At low temperature battery capacity goes down hence batteries should be covered with a tarpaulin sheet or be stored in a warm place when not needed Keep the specific gravity of battery electrolyte above 1 25 so as to prevent it from freezing Refer to Par 6 4 Batteries Chap 3 5 Warm up the engine well and never overstrain it During operation watch thermogauge and if it gives any sign of overcooling put a cover on radiator 9 HANDLING IN THE HOT SEASON 1 2 3 4 Use engine oil intended for summer Refer to Chap 2 Engine Oi Keep the tension of fan belts properly adjusted so as to allow them a slack of 12mm Refer to Par 5 3 Tension of fan belt Chap 3 Watch thermogauge too When cooling water has started boiling from overheat Don t stop the engine at once but let it idling for a time Waiting for water temperature to fall Check battery electrolyte level every day and if lower than specified add distilled water f When the engine is to be left idle under high temperature for several days or longer store batteries in a cool dark place to prevent their self discharge 1 FUEL CHAPTER 2 FUEL OIL AND COOLING WATER 1 Fo
52. he engine makes it run at a lower speed than equivent to the Venturi opening for example lower than A even at 10096 of Venturi opening in the diagram control rack is pressed over its whole travel to full load stopper making it to develop max torque If tough torque is required of the engine governor is equipped with a buitin torque spring angleich spring This type of governor requires especially perfect air tightness of air pipe and intake system for lack of their air tightness will much affect its performance and cause particularly overrunning Into air chamber for atmospheric pressure in diaphragm block negative pressure is lead from inside paper element of air cleaner through vinyl tube so as to compensate the change of resistance the might arise from its clogging Being of sheep skin diaphragm in diaphragm block requires regular lubrication Refer to Lubrication When a sudden unusual change noticed in idling have it checked by your dealer or at a service shop as it is suspected to be broken from aging Each time to apply oil to diaphragm loosen red plug on the side of diaphragm block to draw off the excess of diaphragm oil or fuel collected there from pump If too much fuel found there make necessary repairs In any case whatever don t tamper with the seals on Fig 3 26 3 27 Injection pump full load stopper Sea 1 Diaphragm block cover Seal 2 Idling sub spring Seal 3 Venturi lever stopper full open s
53. ide Seal 4 30 Fig 3 26 Diaphragm block of governor Fig 3 27 Venturi unit 4 7 Governor mechanical 1 2 Model 4DQ50 Engine is equipped for governing of its speed with mechanical governor centrifugal type which connected directly with fuel injection pump camshaft This governor is RUV and ali speed type so it controls not only max min engine speed but also can control every engine speed by control lever position As mechanism illustrated Fig 3 28 two flyweight combined with governor shaft and rotates through the gear which equipped with camshaft and centrifugal force of weight conducts to the governor sleeve in the governor sleeve angleich spring is equipped Centrifugal force of fiyweight and control spring force act to this spring so it works as angleich Control spring is installed to the adjusting lever s shaft and one end of spring put to the spring seat Control spring force changes by this lever s motion The lower parts of floating lever is combined to supporting lever and this position is determined by full load stopper Sliding peace which is equipped in the middle of the floating lever inserts governor sleeve groove and works with movement of sleeve and move the control rack which connected with upper parts of the floating lever The arm which connects floating lever and control rack is equipped with start spring and one end of spring is connected with governor housing This spring always p
54. ine as level as possible 1 LUBRICATION This section covers the points of lubrication which is a basic factor of maintenance It is most desirable to use the classes of oils recommended in the preceeding chapter i Engine oil pan Checkup of oil level 1 Drain plug Fig 3 1 Checking oil level Fig 3 2 Drain plug on oil pan Check it every morning or prior to starting Checking procedure is described in Sect 2 Checkup and Preparations prior to Starting Chap 1 Change of engine oil Every 250Hr of run or when bypass alarm has got alight change oil In new engine change it after initial 60 Hr of run For complete change of used oil drain it off screwing off drain plug on oil pan while it is still hot i e a little after the engine stopped At the same time empty oil filter and oil cooler if attached too and replace oil filter elements When used oil has all drained off pour in the specified quantity of new oil through oil filler on the side of crankcase or rocker case cover let the engine run at idling for several minutes and stop it and check oil level with level gauge Note Standard quantities of oil for 4DQ50W is 4 7 litres 4DQ50 is 6 0 litres 4DQ50P without oil cooler is 6 7 litres 2 Fuel injection pump cam case Chockup of Oil level Every 120Hr of run pull oil level gauge 1 out of injection pump cam case and check oil level If it tells a decrease of oil Check and repair the leak Standard
55. injection 1i tigh E CISCO of PITS Secs aot Teak ER 2r j UCET 229 pooo O peomhsms damp 5 707 igen 209 pomem 07 praade 79 osmon we Te _ DIET Priming purp 76 Suction capacity No air leak in a Leak Bu h rod and s than between not more than 30 Strokes Shorter than 45 sec mo ee li Bearings eus Axial EET E 0 030 05 LH and Standard ime ere hole inner diam 0 osmoso Pin outer di stan o i wis li a Pump body 77 Suction capacity Injection pump Tappets Floating 5 bushes andjd ram rol lers i A i Varies 1 m per 0 1 Adjust with shims shim uite em p mm of Check wi th hand tester at Must inject in a straight cone approx of gas oi igmee of fine spray without dribble rature Wash in gas oil If and under gradual apol ication Cleaning not effective replace of pressure make throttle nozzle tips injection Wash or replace nozzle tips If needle bearing scratched D D dge from discharge pressure test 0 2 Overall play less than ee 0 075 With discharge port plugged up apply 2kg Ccm of air pressure then put whole pump in gas oil Moving priming pump handle at about 0 strokes per min see how many strokes required to digcharging Su
56. instructions 63 2 Cylinder head and valves 70 2 1 Reface of valve seats ee ee eee eee 70 2 2 How replace valve guides 70 2 3 Combustion chamber jet and director 70 2 4 Rocker shaft brackets 71 3 Pistons and connecting rods 71 3 1 How to remove and install piston and connecting rod 71 3 2 How to couple piston with connecting rod 72 3 3 How to remove and install piston pins 72 4 Cylinders an ete eee tree nsec eens s 73 i Acie ts e oai i vasa ee 73 42 QCylinderliners i i samo Re Ry ene bine o REIR Sa 73 5 Bearing metals o Rr cee Sk Ba Rue daca ole e een ica he ass E 73 5 1 Generalcautions c eee hee eee tia e e eae Me Reis 73 5 2 How to assemble main bearing metals mg Piu Red eua aera Se 74 56 3 Underszes o n re e ce yai IR RR YU 74 6 Timing eR e rie aha eats Hs 74 6 1 Timinggeartrain eese hA 74 6 2 Walvetiming o Slew m aries ne e dire e s go ngon 75 Fe LOW oae sees pA eS qua erste sorte QURE Crema 76 8 Mountings c s o ew ee set eh A ahs Os He ELS VY 76 9 installing o
57. iven blow S29 S 0 007 1 20 S Hydrometer reading S30 Specific gravity at 20 C t Electrolyte temperature C Long use of battery in insufficient charge will do damage to its pole plates resulting in a remarkable drop of its efficiency Make it a rule to recharge it before it gets discharged any more than 1 2 in winter a fall of temperature involves a sharp drop of its capacity Remember especially that a decrease of specific gravity in inadequate charge might make electrolyte ready to freeze in a cold area Refer to Sect 8 Handling in Cold Weather Chap 1 3 Good battery maintenance requires moreover such cares as mentioned below a Keep battery always clean and dry b Connect terminals always firmly Corroded parts of terminals can be easily cleaned by washing with solution of sodium bicarbonate But be careful not to splash it into cells After polishing terminals weli connect them firmly and give a thin coating of grease Never try to hammer or hit them off or on IL c Don t put any metal articles such as pliers and spanners on battery Such careless doing will short circuit it with a spark and might cause a serious accident to say nothing of early break down of battery nor bring naked fire near it 7 RE SCREWING OF MAIN BOLTS With initial fatigue of gaskets and packings in newly assembled engine and with its long use bolts will get loose To prevent accidents arising therefrom check main bolts at r
58. manifold Defective valve seats Sticking valve stems Failure of rocker arms to lift valves Wom cylinder pistons or piston rings Sticking piston rings Exhaust gas leak in cylinder head gasket Worn or broken valve springs Insufficient torque of starting motor at starting 66 Repair Flush Repair and replace if necessary Change element and oil Repair Drain oil to lower oil level Repair and replace parts if neces sary Repair and replace damaged rings if necessary Replace valve guides Overhaul engine if oil laden gases are exhausted Clean and replace element if necessary Wash interior Check and clean Repair Repair and replace valve stems if necessary Adjust valve clearance to 0 3mm 0 012 mm Repair and replace parts if neces sary Replace damaged rings Retighten and replace gasket if necessary Replace parts Failure of radiator to dissipate heat properly Radiator dissipates heat excessively Jammed moving parts Insufficient coolant Overheating Water leak in unit seal of water pump Crack in crankcase water jacket Water leak in other parts Air in cooling system Rust and scale deposited in radiator Dust and dirt around radiator Slippage of fan belt Inoperative thermostat kept closed Extremely low atmospheric temperature Uncovered radiator Inoperative thermo
59. n Finally screw bolts 4 pieces each in front and rear uniformly in order not to strain packings Fig 5 13 Arrangement of oil pan ckin 10 OIL PUMP nm In fastening down pump case cover align its setting mark with that on pump body Pump case Grease Water pum pulley Impeller Unit seal Cover Fig 5 14 Water pump 11 WATER PUMP If any play developed on water pump shaft or water leaking disassemble pump in the following procedure and service as required First remove fan coupling flange with puller and take off snap ring Then open rear cover and take out inner components Impeller can be pulled cut with puller Check unit seals and if badly worn or affected in floating seat surface or carbon worn off renew them Of new bearings grease may come out a little but this means nothing particularly wrong 12 BOLT SCREWING 1 For screwing of main bolts the necessary instructions were already given in Sect 7 Re screwing of Main Bolts Chap 3 The other bolts should be screwed with reference to the following table maes 3 St m m E 4 Clamping k gm 0 7 feib 50 2 Prior to screwing the following bolts coat their threads with oil proof liquid packing atmosit for prevention of leakage 4 lower clamp boits on crank shaft rear end oil seal lower clamp bolts on timing gear case 2 clamp bolts on flange plate to couple injection pump 2 fixing bolts on breather 3 Packin
60. n relation to applying to generators and general power plants continuous day and night running operation should be performed within about 90 of the rated output Concerning overload 1096 of the rated output is available for one hour Detail of specifications of marine engine is showed an another seat catalogue of Mitsubishi Marine Diesel 104 Output PS Performance Curves of Model 4DQ50A Engine for Motor Vehicles Equipped with fan air cleaner and generator not loaded Air temperature 15 C atmospheric pressure 760mmHg relative humidity 0 4DQ50A REN gd EL uc ques 1000 1500 2000 2500 3000 3500 3800 Engine Speed r p m 105 r ps h Fue Consumption Output PS Performance Curves of Model 4DQ50C Engine for Construction Machine Equipped with fan air cleaner and generator not loaded Air temperature 20C atmospheric pressure 760mmHg relative humidity 6596 ae p BS ONERE ES E 1000 1500 2000 2500 3000 Engine Speed 106 230 210 190 Fuel consumption gr ps h Output PS Performance Curves of Model 4DQ50P Engine for General Power Equipped with fan air cleaner and generator not loaded Air temperature 20 atmospheric pressure 760mmHg relative humidity 6596 4DQ50P sis 1000 1500 200 2590 3000 Engine Speed 107 Fuel consumption gr p
61. ne proper Electrical system Cosi orton auto BEP RIPE P LEES PHI ji Uii d d A BR PL 4 Bland engi Pe cde i g d crank engine Engine can be cranked manually o Engine cannot be cranked manually Heater plugs do not glow red Heater plugs glow red too early Atte exhaust smoke Too much white oxhaust smoke Too much black exhaust smoke merits exous neq spa cuiu White exhaust smoke Black exhaust smoke A Engine knocks excessively Engine is noisy Engine runs irregularly When operating For detailed information refer to the separate table silo lw 2 3 38 2 121218 18 sie 51 15122 2 58 2 p x 5 E 28 23 8 Possible remedy gi 2 2 s E sizis 8s 53 o win A amp S813 6 Ss O jela e 9 2 of 8 2 902 3 8186815 1318 ay 512515 jas jag slel lFSlesie Sle 2 ofc E gels 3 8 SSE B5E3 s g e Re o gt o EDE Leg gt S sels j i amp Es ESI s se 82 95 571551552155 95 95 Sale ok x ats jaje 55 2514 515 Riese ERREEN HAE Adjust full load setting of governor ttom side at warm up Heats oil pan Bs from bo engine 5
62. ner and oil bath type cleaner 1 Quantities of oil and change of oil refer to Lubrication 2 3 4 5 6 Pre cleaner gathers comparative parge dirt Oil bath gathers comparative small dirt If the oil is not fluidity by very small dirt change the oil in spite of the existence of sediment and servicing interval For washing the oil At the same time wash the lower element Be care not to tamper the air cleaner during engine opera tion Be care not to leak from connecting pipe If the dirty air enter the cylinder it injur the valves and cylinder sleeves and Pre cleaner _ Fig 3 8 Air cleaner Oil bath type in the case of pneumatic governor use it gives bad influence to the governor action 2 2 Air cleaner Filter paper type In filter paper type air cleaner paper element performs an important part handling be very careful not to rub or scratch its surface If scratched or damaged even a bit replace with a new element A thin pipe from the case is connected with a vinyl tuve to diaphragm air chamber in pneumatic governor Refer to Par 4 6 Governor Keep this tube firmly connected If off it will let in dust 1 2 Every 250Hr of run take out element to clean by blowing air from inside At the same time clean the interior of case If compressor not be available tap element clean of dust Never wet it with water When the engine used in a very du
63. njection rate S8mmYtrev cyl loose Error intermediate angles between 2 5 at 750 npm and 8 5 at 2 000r p m must be less than 0 75 C 50668 50100 DP200 122 R Relay for joint use 30668 26200 RH200 12D 85g 5 thick and 20 wide Crank pulley pitch diam 1202 Generator pulley pitch diam n Revolution ratio 1 69 Charge alarm lamp gets alight below 880r p m of engine speed Switched on e T Starter 12V regulator Shaft and brackets Setting Limit of Standards Repair Clear ance Terminal Generator voltage lon load 14V below 1 050 characteristics r p m Per formance Load 26 below 2 500 characteristics r p m Point gap 0 3 0 4 Air gap 0 8 1 2 Back gap 0 87 1 1 Non load voltage 4 0 15 5V regulation at 4 000r p m Commu tator side braciet outer diam inner diam and standard clearance Opposite bracket outer diam inner diam and standard clearance Pinion outer diam pinion metal inner diam and Standard clearance Limit of Use Remedies Remarks 50666 23108 1 5B 10072 95 em Setting o Shaft and Middle bracket outer diam inner diam and 40 840 942 standard clearaace Canmutator 127 Eccentricity Runout RI less than 0 05 EE miei eS Brushes mmus nee rom ww Gap between pinion 151 stopper and pinion when pushed ahead by lever Switch on voltage wi
64. ntrol lever of the governor is attached to either side left or right of the shaft of the swivel lever according to the order Along with the rotation of the control lever the swivel lever will begin to revolve and 35 Fig 2 the length of the arm of moment against the revolving axis will change together with the tension of the governor spring This is because as aforesaid that the revolving center of the swivel lever and the spring eye of the tension lever are eccentric each other The set load of the governor spring may adjust the adjsuting screw of the knackel The stopper bolt attached to the back of governor cover may be adjusted so that it will contact with the knuckle when the control lever barely reaches its STOP position In the governor equipped with a stop device this stopper bolt may be used as a idling stopper The ungleich equipment may be screwed in the tension lever if necessary This is a bush with a pin having the spring load and may be controlled from outside by taking off the closing cover of the governor cover as it is designed The ungleich device will amend the full load jet volume of the injection pump within a specified scope according to the set load of the spring which is adjusted by the constant of equipped spring stroke and shim so as to be fit successively for the necessary volume of fuel for engine between the r p m of idling and that of fuli load The adjustable screw bush is inserted in abo
65. of our conventional type hand timer but has inside two legs that project in the same phase with flange teeth and keep contact with the curves surfaces of the flyweights In these legs are machined the other seats for timer springs Each timer spring is held in the said pair of seats that is in the bearing pin by one end and in the leg by the other These major components are housed in timer case which is screwed to the flyweight holder Fig 3 33 A shows the time at a standstill Being free from centrifugal force the flyweights do not lift at all and timer springs are now longest in their setting length Fig 3 33 B illustrates how the timer works at the max engine speed Centrifugal force is now making the flyweights lift In the picture the letter B indicates flange leg whose phase with the pump driving shaft of the engine is designed to remain constant So the lift pulls bearing pin A over the distance E which results in turning the pump camshaft on the driving shaft so as to put ahead the injection timing CURVED SURFACE A ATA STANDSTILL B AT MAX SPEED Fig 3 33 Timer flyweight The timer for Model 4DQ50 Engine is intended for clockwise revolution and provides a max angle of lead of 6 as measured on the pump camshaft At a standstill it keeps the injection slowest The automatic timer was assembled with 150gr of grease inside and unless leaked by chance needs not be refilled When the timer disassembled change grea
66. or affected assemblies In taking apart the main parts such as pistons connecting rod vaives and metals arrange then or put numbers on them in an appropriate way to place them later where they were Remember particularly that caps on connecting rod and main bearings being machined in pairs with respective bodies cannot be replaced separately When the engine overhauled make every service specified in Retular Checkup and Service Table After a thorough overhauling practice an adequate running in and performance test on bench coupling it with a dynamometer so as to adjust it perfectly for actual operation for example on the vehicle For fuel injection pump and governor they must also be tested when overhauled individually on a fuel injection pump tester in order to make necessary adjustments New units supplied an integral assembly injection pump general ass y can be readily put in service as already adjust thoroughly For informations about the engine bench test and individual adjustment of injection pump and governor ask your dealer or service shop Reference to Parts Catalogue will greatly help you in knocking down and reassembling the engine Remember that special tools are available for those operations Refer to Chap 6 CYLINDER HEAD AND VALVES 2 1 Reface of valve seats Valve seat angle is 45 After a rough machining with a 45 degree cut ter give perfect fitting Standard
67. p through piping by which it is discharged into fuel filter where it is filtered clean thence is runs into fuel injection pump to be ejected under control of injection rate according to the load and under high pressure into combustion chambers via injection pipes and nozzles For stopping and cold starting control of injection rate can be done with stop lever but in other cases should be left to pneumatic governor that works by Venturi negative pressure INCREASE Fuel injection pipe NEUTRAL 2 Fuel injection nozzle X FUEL RETURN Bleeding pug Fuel filter E Fuel injection S DECREASE Stop iever Overflow pipe Drain piug Fig 3 14 Fuel system diagram 4 1 Fuel filter 1 Every 120Hr of run screw off bleeding and drain plugs to drain off dirt and water settled at its bottom then screw in drain plug and make a bleeding or priming 2 Fuel filter element is of paper When it gets clogged with dirt fuel feed makes a drop Replace it with a new element every 1 000Hr of run To wash it in 22 3 4 cleansing oil will remove dirt on the surface but surely affect the texture of paper involving a drop of its filtering efficiency When filter disassmebled for that wash the interior of filter case clean of dirt After assembling it with a new element in make a bleeding or priming without fail Bleeding plug Joint on the side of filter case is inlet and that on
68. phragm by Vertui negative Pressure idling sud spring action range Main spring action range Torque angieich Spring action range Injection pump rack position Increase of injection Fig 3 25 Diagramatized principle of pneumatic governor operation Now suppose that max engine speed needs to be governed at A rip m While with Venturi butterfly valve opened 10096 main spring with setting load equivalent to governing force Fc that is produced by negative pressure C at point B on Venturi negative curve Fig 3 25 is placed on diaphragm When the 3 4 5 engine tries to run at a higher speed than A r p m a consequential rise of negative pressure provides greater governing force which compresses main spring against its setting load thereby pulling back injection pump control rack to reduce injection and as the result engine speed is slowed down to A r p m When on the other hand engine speed is made to fall below A r p m a decrease of negative pressure lets main spring press control rack ahead to rise injection rate whereby it is vised back to A r p m Meanwhile the more Venturi butterfly valve throttles the quicker rise of negative pressure to engine speed can make engine keep low constant speed by producing governing force Fc Governing the engine speed thus in one to one proportion to the percentage of Venturi opening this governor is called an all speed type In case heavy load on t
69. ping down timing gear case and rear end oil seal The part to install front end oil seal has concentrically machined periphery Center the seal so as to fit to it Meanwhile for rear end oil seal center it on basis of its periphery In either case a special centering tool is available Remember that rear end oil seal must be set with oil leak off knotch in slinger down Prior to installing oil seals coat their lips with pure engine oil 8 MOUNTINGS On motor vehicle rubber cushions on front mountings form a paralle logram in free condition as shown in Fig 5 12 and a rectangle under load Remember this in setting them On construction machine three point support mounting is used Timing gear side has cushion rubber P N 4A lt f Fig 5 12 Mounting on motor vehicle in free condition 9 OIL PAN INSTALLING Oil pan of Model 4DQ50 Engine is designed so as to be installed with its center in alignment with those of crankcase and crank shaft At either end fasten it tight enough not to leak Main bearing caps on both front and rear ends have grooves Fit retainers in those grooves as illustrated in Fig 5 13 Then to their corners put the ends of side packings cork plates and fit semi circular rubber packings in the grooves To apply liquid packing to corner intersections will prove very effective in preventing leakage Coat semi circular rubber packings with oil on the surface so that oil pan edges will slide easily o
70. pped with fuel feed cock make sure that it is open At starting after long leaving idle or when air seems to be in fuel system practise bleeding or priming Refer to Bleeding Pneumatic governor Fig 1 2 Around Venturi lever Fig 13 Around Stop lever 4 Power source Make sure that battery switch and battery terminals are on Now check as follows and proceed to starting 1 That the engine is clutched off or free from load 2 That stop lever is not in stop position 3 That venturi lever is in full open position for pneumatic governor use 3 ENGINE STARTING Model 4DQ50 engine is equipped with either of push button or key type starting switches In push button type switch a press on button keeps it on until another press on button S makes it pop out automatically 1 Putkey into starting switch 2 Press button H or turn key counterclockwise to make glow plugs red hot Pre heating time depends upon air and engine temperatures In any case pre heat until glow plug indicator becomes red hot Usually some 25 seconds pre heating will make it red hot If it gets red hot too early or too late check glow plugs for that is an evidence of one or more of them breaking Fig 1 4 Push button type 1 Starter switch starting switch 2 Glow plug indicator 3 Engine stop button Fig 1 5 Key type starting switch 3 Then press button S or turn key clockwise to switch on starter Wh
71. r fuel use gas oil with greater cetane number than 45 of a well known and reliable brand and destined for high speed Diesel engines 2 Use of clean fuel is of greatest importance for the fuel system of a Diesel Dust and water in fuel do damage to precisionmachined injection pump nozzles etc In filling fuel tank take care not to let in any bit of dust and water The refilling of fuel tank should be done after the operations are over At regular intervals open drain cock on fuel tank to draw off settled water and dirt prior to starting and wash its interior 2 ENGINE OIL 2 1 Quality required of engine oil A high speed Diesel requires for its lubrication better quality mineral oil than that intended for ordinary gasoline engines It means that such oil satisfies the following requirements 1 2 To be stable against heat and oxidation By high heat of cylinders oil is subject to oxidate and carbonize and consequential collection of carbon and residues leads to wear and seizure Therefore oil needs to contain at least two kinds of additives to improve its stability an anticorrosive and a detergent that dissolves carbon and sludge in oil and thus washers them away From these view points use always H D type that contains both so is very favourable for the service life of pistons liners rings and metals etc To have high viscosity stability against changes of temperature For easy starting at low temperatu
72. re oil is required to be low in viscosity but after starting be high enough to assure perfect oil film on high temperature parts Practically however a single oil cannot opportunity satisfy these requirements so it follows that an oil whose viscosity is less subject to change should be used 2 2 Recommendable classes of engine oil In view of the foregoing requirements DM class in A P l s service classification should be chosen As for viscosity selection consult the following table zx ox Climates Above 40 40 5 C 5 15 Below 15 C SAE 40 SAE 30 SAE 20 SAE 10W Except in an frigid region SAE 30 can be applied throughout the year 2 3 Time to change engine oil Time to change engine oil is indicated as a general standard in Lubrication Table it may however get dirty and deteriorate very soon and need to be changed much ahead of the given time under some conditions of use and be very show to do so under others Practically speaking the user himself should judge whether it can stand further use or must be changed For this we recommend a simple test called spot test where some drops of used engine oil are put on filter paper to see how far it has deteriorated and got dirty For details about this test ask the manufacturer of the oil 3 DIAPHRAGM OIL Pneumatic Governor Diaphragm oil is a kind of leather oil intended to prevent the aging or deterioration of she
73. right side of crankcase They will serve as important data to know the engine s career and make up of components Fig 0 1 Stamped engine No Fig 0 2 Service meter As for fuel engine s power source and lubricating oil to smooth engine operation please use those are above DM class as shown in caution plate Their choice has a considerable influence on the engine s service life Lubrication and other servicing in accordance with the instructions given herein will promise its most satisfactory operation For regular service intervals are based on the reading of service meter don t forget to read it every day At the same time check the day s fuel and oil consumptions The data collected thus every day will prove very usefui to know later how the engine has been running and is at the time We hope that along with this manual you will make use of the parts catalogue to deepen your knowledge about the handling of your engine 1 follows with the engine placed as level as possible and lower one If near or below the mid point CHAPTER 1 OPERATION AND HANDLING NEW ENGINE Prior to putting it in use check as follows 1 Seeif there are any loose bolts or nuts 2 Lubricate according to Lubrication Table given later 3 Fill fuel tank with clean fuel and bleed or prime fuel system 4 Fill radiator with clean soft water as a ccolant When air temperature is expected to fall below the freezing point use an antifr
74. rminals inspect brushes at times re move carbon particles from around them and make sure that they move smoothly in their holders If badly affected in contact surface or worn Field coil Armature Fr bracket Re bracket Pole piece Yoke Pulley with fan more than 11mm in height Fig 3 40 Generator Section D C generator replace with new brushes High Mica Standard Mica 0 50 8 mm Standard intervals to replace Segment setting new brushes polish ONS A M um them with 250 sand paper so Fig 3 41 Wear of commutator them are 500Hr of run In that they make uniform contact with commutator over the whole surface 3 Inspect commutator every SOOHr of run If affected polish clean with 400 sand paper and wipe with clean cloth wetted with gasoline Mica pieces must be 0 6 0 8mm below commutator surface If out undercut them accordingly 6 2 A C Generator Fr bracket r4 Fig 3 42 Generator Section A C generator This A C generator is differently from a conventional D C unit built so that the armature is installed outside and the field is turned inside as a rotor It features among others an extremely long service life of the brushes and ability to operate at a very high r p m because the arrangement dispenses with commutators and subjects the brushes only to a small current while its field has very simple make up as compared with the armature of a D C generator and it is free from the nee
75. rnor Ditto above Specified separately Refer to Trouble Shoot ing At 20 00 of oil and water Ditto above At 70 of oil temperature INLET VALVE EXHAUST VALVE CLOSES NLET VALVE EXHAUST VALVE OPENS CLOSES Hone tot0 25 40 50 or 40 75 on EU a rsize S worn beyond limit of use e Re grind to minimum required Use oversize pistons accordi to Qol 8 Oversize 0 22 Te 0 50 and 0 75 Hone 4 cylinder to equal over size Change of liners is desecribed separately t 0 95 0 15 Till worn up to limit of use 0 10 pistons replacing rings once 0 10 limit over replace pistons Till worn up to limit of epair replace piston pins Piston pins 5 0 6 r S once limit over replace pistons 81 Main moving parts Engine body 2 Piston rings rods Oonnecting S in Sample84440 011 7 Inner and outer diams Te 0 020 0 051 0 08 Bs gar cleara n g 6555798 E TEE ENT wee aser 0 20 Pi rod Inner and outer diams dra 58 0 055 0 100 large erd and standard clearance 0050 Inner and outer diams Journals and 25 65 4 0 030 0 089 generat and standard clearances main bearings nd T Henane e erem 0 05 fimgiicend gak piston p Mis 15 Cut end clearances 2nd in free Out erd clearances 2m 161 When fitted with si Oylinder head EE
76. s case The tension of the governor spring and the moment arm concerning the revolving center of the tension lever are increased the governor spring pulls back the tension lever until it comes in touch with the full load stopper and the tension lever pushes the shifter and guide bush to the side of the injection pump by pushing them Shifter amp Guid bush Ungleich Str oke Fig 6 The starting of the Ungleich at the low r p m full load The guide lever the floating lever and the link will push the control rack to the full load position by transferring the action to the lever To transfer the control rack to the full load position it is enough to move the control lever slightly from the idling position Then the ungleich spring in the tension lever if the spring is involved in it becomes effective The injection pump supplies much fuel to the cylinder of engine and the r p m rises As soon as the centrifugal force exceeds the tension of the governor spring the flyweight will spread itself outside and pulls back the guide bush shifter floating lever and the control rack in the direction of decrease The r p m of the engine will not rise from this point and it is maintained by the governor under a fixed condition When the control lever is transferred to the position of the highest r p m Fig 7 the governor works as shown in the Fig 6 as aforesaid Full lood di Control i Storfing of Ungleich stop
77. s h 99609 50000
78. se for new one 4 9 Measurement of engine speed 1 A drop of engine speed below the specified level will disturb the engine working up to the given efficiency while a rise above it will cause the overrunning of the engine itself or of the vehicle it drives Therefore both max and rated speeds must be always as specified 2 As mentioned before pneumatic governor governs engine speed in one to one proportion to the percentage of Venturi opening hence permits the engine to 3 4 run at max speed when Venturi opening is 10096 It should be noted that the governing efficiency depends much upon how the air system is especially whether or not it is perfectly air tight Engine speed should be measured under no load in Model 4DQ50 engines intended for motor vehicles and construction machines non load max speed is 57 1096 over the rated speed How to measure engine speed In case of hourmeter equipment with engine pick up the hourmeter and equip a special parts Fig 3 34 and measured by tachometer in this case tachometer indicates 1 2 engine r p m 30498 01100 30498 01000 Oil pump drive shaft Fig 3 34 0520 07100 L JOINT 20625 23500 SERVICE METER 5 COOLING SYSTEM Thermostat Bypass hose jacket Radiator e lt a pou Io Ny fost n i Fig 3 35 Cooling system diagram As illustrated in the diagram Fig 3 35 cooling water is kept
79. seat width is 1 4mm Excess in width affects airtightness If valve seat has become wider cut the face accordingly with a Margin cutter with an end angle of 120 Usea Seat angie Valve depression cutter of 426 in outer diam for inlet valve seats and of 339 for exhaust ones ping Vaive depression must be within a range Fig 5 1 Valve seat of 0 8 0 2mm fn case valve has sunk more than 1mm which requires a valve seat insert be fitted in ask your dealer or a service shop for the service If valve face scratched or worn replace with a new seat so far as available It can however be ground until margin becomes 1 2mm 2 2 How to replace valve guides To remove valve guide press it down with remover while to fit in a new guide use _ installer so as to set it with the top end 18mm above the surface of cylinder head See Fig 5 2 2 3 Combustion chamber jet and director To remove combustion chamber jet lightly press it out with a long bolt of 100 as illustrated on the right For new jet tap them in uniformly until their surfaces get level with that of cylinder head Setting directions are indicated in Fig 5 4 Having set them right calk each at a spot with a punch To replace directors hammer new ones so as to place jets midway between inlet and exhaust valves as indicated arrows Fig 5 2 Replacement of valve guide Fig 5 3 Pressing out combustion chamber 2 4 Rocker shaft brackets To remove rocker
80. sh the interior of filter case in gas oil or cleaning oil In assembiing again don t forget to place spring and spring seat where they were 3 Carefully examine used element and oil and if many metallic particularly copper color settlings found which is an evidence of bearing metals being abnormally worm take appropriate measures at once Center bolt Differential Ines vale Fig 3 12 filter 3 3 Differential bypass valve This valve is set in oil filter cover The design is such that an oil pressure difference above 1 5kg cm between inlet and outlet sides of filter element arisen from its being choked with dirt makes it open to bypass unfiltered oil directly into main oil gallery in order to prevent any serious Differential bypass valve With switch trouble seizure for ex ample that might be caused TO MAIN OIL GALLERY s FROM OIL PUMP 4 by lack of oil Whenever the Oil filter element valve set to perform so of NS Relief valve which the operator will be signalled by alarm lamp in TO OIL PAN front of his seat element Fig 3 13 Oil flow diagram must be replaced at the earliest possible opportunity for lubrication with unfiltered oil will affect moving parts The above alarm lamp is set alight as soon as the valve opens to perform such an emergency bypassing by contactor that is attached to it for that purpose 3 4 Oil pressure Under ordinary weather conditions and at usual
81. shaft bracket prior to loosing center bolt 1 loose short ones 2 lest bracket should be strained to break In bolting it down screw those bolts in reverse order that is first long bolt 1 and then short ones 2 In setting brackets allot enough clearances to permit both left and right rockers to move smoothly Fig 5 4 Setting direction of combustion chamber jet and director Fig 5 5 Bolts on rocker shaft bracket 3 PISTONS AND CONNECTING RODS 3 1 How to remove and install piston and connecting rod assy In Mode 4DQ50 Engine connecting rod large end has a larger diameter than 7 7 cylinder bore hence piston as coupled with connecting rod cannot be pulled out upward that is toward cylinder head but through the bottom of cylinder with crank shaft off To install piston coupled with con necting rod press it into cylinder from below then install crank shaft To install piston use the special tools But don t forget to coat it with oil in Fig 5 6 To install piston advance 3 2 How to couple piston with connecting rod Pistons and connecting rods are marked with serial numbers No 1 No 2 No 3 and No 4 according to their arrangement as seen from timing tear case How to couple together each pair and to set in cylinder crank case is illustrated on the right 3 3 How to remove and install piston pins Fitting of piston pin is such that does not permit it to be pressed in by hand at normal tempera
82. stat kept open Sticking cylinders pistons or piston rings Sticking main bearings and crankpin bearings Sticking cam bushing and idler bushing Possible remedy Add water to prescribed level Replace part s Replace crankcase Check and repair Bleed air by loosening air bleed plug drain plug or hose clamp Flush Flush Adjust belt tension Replace Cover radiator Replace part s Repair and replace part s if necessary Repair and replace part s if necessary 1 CHAPTER 5 OVERHAULING INSTRUCTIONS GENERAL INSTRUCTIONS 1 2 3 4 5 At present we cannot say when your Model 4DQ50 Engine should be put to a thorough overhauling for it presupposes under what conditions the engine will be sued but can mention as general hints the following cases where an overhauling is required a When engine parts having been uniformly fatigued or worn down from long use involving a drop of output it is judged better to overhaul it b When an increase of blow by out of crankcase has caused a notable drop of engine output c When oil consumption has increased d When with nothing wrong with oil system a remarkable drop of oil pressure is noticed which is judged ascribable to the wear of metals etc e When water leaks into oil f When such a serious trouble has happened inside the engine that cannot be remedied by usual services or permits the replacement of broken
83. sty place do the cleaning at shorter intervals Every 500Hr of run replace element with new one Cleaner case ass y Cleaner cover Wing nut Fig 3 9 Air cleaner filter paper type negative pressure take off port 2 3 Vaive clearances Both lack and excess of valve clearances affect engine performance Especially excessive valve clearances will induce much strain on valve mechanism making the engine subject to serious trouble Apart from regular checking required every 250Hr of run check and adjust them whenever low speed running of the engine makes any unusual sounds For new Engine adjust them when it has run for 6OHr Proper clearances are exhaust and inlet valves alike 0 25mm as measured in cold or uniformly warm engine Firing order is 1 3 4 2 2 4 Compression pressure 1 To see whether or not intake air into cylinders undergoes there sufficient compression with no blow by to help the firing measure compression pressure 2 The results will tell if a Valve seats are in tight enough contact b Cylinder liners and piston rings are not worn or sticking hard C There is any leak of gas ascribable to other cuases Regular measurement at intervals of about 500 of run will provide reliable data to decide when to overhaul the engine 3 Prior to measuring it check and adjust valve clearances so that rockers do not press down valves in compression stroke and make sure that Venturi butterfly v
84. t the engine as free from load as possible If clutch attached disengage it besides shifting transmission gear into neutral Pre heat well by electrifying glow plugs for 307 40 seconds so as to permit ready ignition 1f starting has failed don t switch on starter again without pre heating The moment first firing takes place bring back lever to neutral Further increase of fuei feed will cool combustion chamber hence a lag in perfect firing Even when initial ignition has taken place and been followed by imperfect combustion keep starter running until the engine perfectly catches to gather speed so that glow plugs will remain red hot to help perfect firing Starter has a free wheel which protects it against any damage even when its pinion is kept in mesh with ring gear in that way In any case don t run it any longer than 30 seconds at a time 8 2 General instructions 1 2 3 Unless an antifreeze is mixed in cooling water drain it off entirely after the operations over lest it should freeze up to damages cylinder block cylinder heads radiator etc Use of an antifreeze dispenses with the trouble of draining Choose a reliable brand of antifreeze that contains a suitable proportion of anticorrosive and mix it according to the manufacturer s instructions given on the can for its proportion usually depends upon the lowest temperature expected Quantity of cooling water for 4DQ50W is 10 litres and 4DQ50C is 16 litres wit
85. th 12V Starter 135 Axial gap to riag gear gap to ring gear Terminal 25 Per formance Non load running speed Load diratoristic Binding torque 500A Front metal inner diam shaft diam and standard clearance Rear metal inner Shaft and diam sbaft diam Brackets and standard clearance Center metal inner diam shaft diam and standard clearance Diameter Height Strength of spring 15 Pinion Gap between pinion stopper and pinion Axial gap to ring gear 96 Limit of Use 418 10 Starter Speed above 3 000 r p m 1900 rpm 0 a ot H 159 kg Remedies 6 5 thick and 19 wide od ITeminal Starter Voltage Current speed Torque above 4000 rpm below more 700 A than 5 1 kgm 98 Limit of Use Remedies Rem arks 99 CHAPTER 6 TOOLS 1 COMMON TOOLS The following tools are supplied for routine servicing Socket wrench 27 31391 02300 To screw nozzle holders Socket Wrench 12 31391 12500 To screw glow plugs Handle 126 x 250 30091 01900 For above tools 1 amp 2 Thickness gauge 03714 63000 To check and adjust valve clearance Cranking handle 30691 11800 To turn crank shaft Other ordinary tools such as mentioned below will be necessary too Double end wrenches spanners 8 26 Adiustable wrench monkey spanner 10 Iri Fig 6 1 Common Tools Pliers Screw driver 150 100 2 SP
86. ting lever contacts with the control rack of the injection pump on the upper end of the revolving axis through the link which involves the leaf spring the link pin and the split pin The start spring is attached to the other end of the floating lever This spring is operated at the r p m lower than that of the idling One of the ends of this spring is Adjusting chim Fig 1 connected with the eye of the pin which is inserted in the governor housing The pin to which the guide lever is attached like a bob holds also the tension lever likewise When the strong governor spring contacted with the eye of the short rim of tension lever is strained the tension lever is pushed to the shifter and the governor spring is streched until the centrifugal force yielded by the rotation of engine balances with the spring force In case when the spring force is stronger than the centrifuga force of the flyweight the tension lever will move until its lower end contacts with the adjustable full load stopper The revolving axis of the swivel lever is inserted in the governor bush and the center of the lever is slightly eccentric against the spring eye of the tension lever The other end of the governor spring is connected with the knuckle which is attached to the upper end of the boat shaped swivel lever There are two bosses on the side of the boat shape which will touch with the side of guide lever when the engine is stopped so as to complete their work The co
87. topper Seal 1 Torque spring Seal 2 Fig 3 31 RUV Governor GOVERNGR Model RSV bosch type 1 STRUCTURE AND OPERATION Fig 1 is the open up view of the sectioned governor and its parts and Fig 2 shows the disposition of such patts _In the RSV type Mechanical All speed Governor the flyweight hoider and flyweight of the revolving part of the governor are attached to the comshaft of the injection pump The two flyweights revolve around the flyweight pin which is inserted in the flyweight holder and when the flyweights opens themseives outside the shoulder of the guide bush is pushed by the roller toward the oxis The guide bush sliding on the cylinderical surface of flyweight holder may move freely with the flyweight holder and the guide bush is contacted to the shifter by means of bearing The shifter may be moved only longitudinally toward the axis The trunnion of the shifter is inserted in the guide lever which hung by the pin of the governor cover like a bob and prevents the rotation of the shifter A pin is attached to the position slightly above the coupling point of guide lever and shifter with wax The floating lever is attached to either left point or right point of the pin so that the floating lever may revolve the left or right point of the pin may be fixed the side of the governor to which the governor pump is attached The pin attached to the lower end of the floating lever with wax is inserted in the fork The floa
88. ture So warrn up piston in boiling water to expand the inner diam of piston pin hole then remove it or install by hand Never hammer it in cold piston No 1 ca No 2 X Arrangement of piston rings on piston is an shwon in Fig 5 8 Combustion chamber side Cam shaft Stamped match mark side Fig 5 7 How to couple piston 1 Compression ring 2 Gil ring and connecting rod Fig 5 8 Arrangement of piston rings Top and oil rings are chromium plated in sliding surfaces while the other namely 2nd are tapered install these taper rings with marks UP on cut ends up To oil ring is attached a spring type expander to provide high and uniform contact pressure The ends of spring are butted to each other with a short steel wire between them Arrangement of piston ring cut ends is indicated in Fig 5 9 Fig 5 9 Arrangement of piston ring cut ends CYLINDERS 4 1 Oversize In Model 40050 Engine cylinders being cast in one body with crankcase have dry liners When they have got worn more than 0 2mm in bore or cut deeply in lines machine them to a suitable oversize Oversize pistons and piston rings are available in three sizes 0 25 0 50 and 0 75 4 2 Cylinder liners If oversize parts are not available or when they have got worn over the limit of use 1 20mm change cylinder sleeve For details ask your dealer or a service shop BEARING METALS 5 1 General cautions Handle metals on main bearings an
89. uel particles and must break clean off without leaving any drop of fuel around Fig 3 20 Nozzle spring shim injection orifice In handling nozzles follow the instructions given below 1 Each time to remove nozzles clean off dust from around them in advance lest it should on packings on their tips 2 In leaving nozzles off put caps on their inlets to keep off dust 3 Never change the combination of needle valve and valve seat This must be remembered particularly in removing nozzle tip from nozzle holder for replacement 4 If nozzles stained with carbon and sludge scrape them off with a piece of wood or such like soft material Never pick injection orifices with a wire etc 5 To service nozzle tips wash them well in clean cleensing oil carefully fit valves onto their respective seats in oil and after washing them clean once more put together in clean gas oil Never wipe them with waste cloth etc 6 Nozzles usually let a little fuel go back Excessive increase of return fuel is an evidence that they must to replaced with new ones 7 To install nozzles clean off carbon from nozzle seat packings but be careful not to scratch or otherwise damage seats Any seat notably sunken in the surface must be replaced for it will spoil air tightness of cylinder even if clamped down tight To install screw nozzles by about Skgm of clamping torque To strain them 4 4 Fuel injection pump 1 2 For checkup of oil level
90. ull the contro rack to the fuel feed increase and increase of fuel feed at starting In the case of torque spring equipped torque control lever is installed and upper parts of lever touch to the torque spring adapter and lower parts touch to the spring seat and act to reduce the control spring force by torque spring force Stop lever which is installed to the upper parts of governor housing pull back the control rack to the position stop Torque control lever Floating lever Praeger Stop lever shaft Oil inlet Floating lever imal gs Timing hole plu Governor shaft g plug Bearing bushing Oil seal Stop Adiusti C E justing lever trol pack Max speed Idling Full loa Stop Torque spring Control spring Supporting point B Spring seat Angleich spring Governor sleeve Flyweight Full load stopper Supporting lever Stopper Supporting point A Governor gear jf 4 Stopper bolt Fig 3 29 RUV governor movement of idling 3 Fig 3 29 shows the situation of idling Flyweight though it is lower speed expand to the outside by centrifugal force overcome weak spring force and push the governor sleeve to the right hand with spring lever Therefore floating lever s supporting point B which touch to governor sleeve 4 move to the right hand as lower part A is supporting point and pullback the control rack to the idling position
91. ut the middle of the governor cover and the idling sub spring which is involved in the bush may be adjusted so that it will affect the control of non load high speed rotation as little as possible However in case when the ungleich is unnecessary at the full load jetting volume but the firm control is needed at a large stroke of control rock at a lower r p m of idling a comparatively weak spring shall be involved in the bush of the ungleich device This spring in case when the engine is an idling condition will push back the shifter from the tension lever which is contacted with the idling sub spring Accordingly the stroke of the controi rack will become larger automati cally Whether the pin attached to the lower end of the floating lever with wax will be inserted in the slot of the supporting lever on the shaft of the stop lever or it will be supported so that it will act at the fork part which is pushed into the governor cover will be fixed as to whether or not the governor has the stop device A governor of standard size has no stop device But the device will be necessitated when you want to pull back the control rack of the injection pump with a slight power without regarding the position of control lever of governor or to use the stopper bolt as the stopper of the limit of the idling r p m 2 PRINCIPLE OF OPERATION The principle of the governor operation is as follows When the r p m of engine increases and its centrifugal foece b
92. volume of the injection pump is adjusted to themaximum r p m of the engine so as to meet the requirement at full load condition the r p m of the engine is lowered and sufficient output cannot be obtained In an ordinary case therefore the maximum jetting volume of the injection pump is adjusted as the dotted line shown in the above figure so as to obtain large torque as much as possible at NI within the low r p m limit As aforesaid without the control given by the ungleich device if the engine is driven at high speed r p m N2 full load surplus fuel will be outlet with smoke The ungleich spring and the stroke thereof shall be adjusted so that the jet volume will meet the fuel consumption at the full load condition in other words the fuel demanding curve and the outlet curve shall be adjusted so that they may be in conformity with each other at the time of full load 5 Stoppage of engine An engine having a governor without a stop device will be stopped by transferring control lever of the governor to STOP regardless of the position of the flyweight Slightly before the control lever reaches STOP or before the knuckle come in touch with the topper boit the boss of the swivel lever will push the guide lever and transfer the control rack of the injection pump to STOP through the guide lever the floating lever and the link Fig 11 Idle Knuckle Stop Stopper bolt Flocting lever Guide lever Control rock 59

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