1. Technical Bulletin Bulletin No PRO 01 18 Effective Date 6 15 80 Cancels NA Page 1 of 1 Subject 284160 TUFLO 500 COMPRESSOR 286551 TUFLO 501 COMPRESSOR CATERPILLAR 1693 ENGINE The installation of 284260 TuFlo 500 and 286551 TuFlo 501 Compressors on the Caterpillar 1693 Engine require the installation of a pilot ring adapter in the compressor flange This adapter Caterpillar part No 9L5412 is initially installed by Caterpillar to align drive components and prevent the movement of the compressor after installation It is important that the pilot adapter be removed and reinstalled on the new compressor when a changeover is made Please note on Catalog Page 01 D 31 TuFlo 500 and Page 01 E 13 TuFlo 501