GROUP 6A - ENGINE MECHANICAL MISCELLANEOUS ITEMS

GROUP 6A - ENGINE MECHANICAL - MISCELLANEOUS ITEMS

1. OIL FILTER LEAKS AT SUB-ZERO TEMPERATURES - 1980-1982 4.1L V-6 EQUIPPED CADILLACS

UNDER EXTREME COLD START CONDITIONS, A HIGH PRESSURE SURGE OF ENGINE OIL ON START UP CAN CAUSE BULGING OF THE FILTER WHICH COULD CAUSE AN OIL LEAK AT THE OIL FILTER SEAL ON SOME 4.1L V-6 EQUIPPED VEHICLES.

THIS CONDITION CAN BE CORRECTED BY INSTALLING A NEW OIL PUMP COVER ASSEM- BLY (P/N 966093). THE NEW COVER ASSEMBLY CONTAINS REVISED DESIGN OIL FILTER BYPASS AND PRESSURE REGULATOR VALVES.

2. CYLINDER HEAD GASKETS - 1980-1982 VEHICLES EQUIPPED WITH 4.1L V-6 (CODE 4) ENGINES

A NEW HEAD GASKET (P/N 25515792), WITH IMPROVED SEALING CAPABILITIES, IS AVAILABLE FROM GMWDD. IT MUST BE INSTALLED WITHOUT THE USE OF ADDITIONAL SEALER OR ADHESIVES. THIS GASKET, BLUE IN COLOR, WILL ALSO BE INCLUDED IN RELATED ENGINE AND CYLINDER HEAD OVEHAUL GASKET SETS ORDERED IN THE FUTURE (P/N'S 25515887 AND 25515889 RESPECTIVELY).

AT GASKET INSTALLATION, THE CYLINDER HEAD BOLTS ARE TO BE TORQUED TO 108 N.M. (80 FT. LBS.) IN THE SEQUENCE SHOWN ON PAGE 6A1-5 OF THE 1982 CADILLAC SERVICE INFORMATION MANUAL.

3. LEAKING OR CRACKED OIL FILTER BASE - 1982 DIESEL ENGINE

A LEAKING OR CRACKED OIL FILTER BASE ON A 1982 DIESEL ENGINE MAY BE CAUSED BY AN INTERFERENCE BETWEEN THE CYLINDER BLOCK CASTING AND THE FILTER BASE. THE INTERFERENCE WILL OCCUR JUST BELOW THE MACHINED BASE MOUNTIMG SURFACE. IF INTERFERENCE IS FOUND, IT WILL BE NECESSARY TO GRIND EXCESS METAL FROM THE CYLINDER BLOCK TO PROVIDE NECESSARY CLEARANCE FOR THE OIL FILTER BASE.

4. 5.7L DIESEL ENGINE - FITTED BLOCK

FITTED DIESEL ENGINE BLOCKS (P/N 22515527 FOR 1982 MODELS AND P/N 2515526 FOR 1981 MODELS) CONSISTING OF A BLOCK ASSEMBLY, PISTONS, PISTON PINS, AND PISTON RINGS ARE CURRENTLY AVAILABLE THROUGH GMWDD.

LABOR TIME GUIDE OPERATION J1800 SHOULD BE USED WHEN REPLACING THE FITTED BLOCK. REFER TO LABOR TIME GUIDE FOR APPLICABLE TIMES.

5. DIESEL ENGINE WITH STUCK PISTON RINGS - ALL DIESEL EQUIPPED CADILLACS

IF A STUCK PISTON RINGS ARE SUSPECTED TO BE THE CAUSE OF EXCESSIVE OIL CONSUMPTION, LOW COMPRESSION, AND EXCESSIVE BLOWBY ON A DIESEL ENGINE, THE FOLLOWING PROCEDURE MAY BE AN EFFECTIVE CORRECTION.

1. REMOVE GLOW PLUGS FROM ALL CYLINDERS.

2. EQUALLY DIVIDE CONTENTS OF ONE CAN OF TOP ENGINE CLEANER (P/N 1050002) INTO EACH CYLINDER. ALLOW ENGINE TO SOAK FOR 24 HOURS.

3. CRANK ENGINE WITH GLOW PLUGS REMOVED TO EXPEL TOP ENGINE CLEANER.

4. REINSTALL GLOW PLUGS AND START ENGINE.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.