OIL LEAK FROM ENGINE TIMING COVER

SUBJECT: OIL LEAK FROM ENGINE TIMING COVER (FRONT ENGINE AREA) (SERVICE PROCEDURE)

MODELS: 1997 CADILLAC CATERA

CONDITION:

SOME OWNERS MAY EXPERIENCE AN ENGINE OIL LEAK FROM THE TIMING BELT COVER AREA (FRONT OF ENGINE).

CAUSE:

THE OIL MAY BE LEAKING FROM THE OIL PUMP GASKET AREA OR FROM ONE OF THE GALLEY PLUGS IN THE OIL PUMP HOUSING OR CYLINDER HEADS.

CORRECTION:

THIS BULLETIN ADDRESSES LEAKS IN THE FRONT ENGINE AREA FROM THE OIL PUMP GASKET AND THE GALLEY PLUGS IN OIL PUMP HOUSING AND CYLINDER HEADS. USE ULTRAVIOLET DYE AND REMOVE COMPONENTS AS NECESSARY TO DETERMINE THE LEAKAGE SOURCE. TO DIAGNOSE OIL PUMP GASKET LEAKS YOU MAY HAVE TO REMOVE THE FRONT AND REAR TIMING BELT COVERS AS WELL AS THE TIMING BELT. HOWEVER, FOR GALLEY PLUG LEAKAGE, DEPENDING ON WHICH PLUG IS LEAKING, YOU MAY ONLY HAVE TO REMOVE THE FRONT TIMING BELT COVER WITHOUT THE NEED TO REMOVE THE REAR COVER OR BELT. REMOVE ONLY THOSE PARTS NECESSARY TO DIAGNOSE AND REPAIR THE LEAKAGE.

AFTER DETERMINING THE SOURCE OF THE LEAKAGE, GASKET OR GALLEY PLUGS, FOLLOW THE SPECIFIC REPAIR PROCEDURE LISTED BELOW FOR THE TYPE OF LEAKAGE YOU ARE ADDRESSING. FAILURE TO FOLLOW THESE PROCEDURES MAY RESULT IN CONTINUED LEAKAGE AND/OR ENGINE DAMAGE.

OIL PUMP GASKET LEAKAGE CORRECTION

THESE LEAKS CAN BE CORRECTED BY INSTALLING A NEW OIL PUMP GASKET ALONG WITH USING A REVISED PROCEDURE EMPLOYING SEALANTS, INCREASED BOLT TORQUE SPECIFICATIONS AND SPECIFIC BOLT TIGHTENING PROCEDURES. SINCE THERE ARE TWO DIFFERENT OIL PUMP AND REAR TIMING BELT COVER DESIGNS UTILIZED ON 1997 MODEL CATERA'S, THERE ARE TWO DIFFERENT INSTALLATION PROCEDURES (SEE "1ST/2ND DESIGN OIL PUMP INFORMATION" AT END OF BULLETIN). CHECK THE ENGINE UNIT NUMBER AND USE THE PROCEDURE WHICH CORRESPONDS TO THAT NUMBER. THE ENGINE UNIT NUMBER IS STAMPED ON THE ENGINE BLOCK JUST REARWARD OF THE OIL FILTER (REFER TO SERVICE MANUAL SECTION "GENERAL INFORMATION" FOR MORE DETAILS). YOU WILL HAVE TO RAISE THE VEHICLE AND MAY HAVE TO CLEAN THE AREA TO SEE THE NUMBER. THE PROCEDURES FOR GASKET REPLACEMENT ARE LISTED BELOW FOR THE TWO PUMP AND REAR TIMING COVER DESIGNS.

FIRST DESIGN OIL PUMP AND REAR COVER - ENGINE UNIT NUMBERS BEFORE 08191279

1. REMOVE THE OIL PUMP AND GASKET PER THE PROCEDURES IN THE ENGINE MECHANICAL SECTION OF THE SERVICE MANUAL.

2. INSTALL A NEW OIL PUMP GASKET, P/N 90572461. BEFORE INSTALLING THE NEW GASKET, COAT THE COMPLETE PUMP SIDE OF THE GASKET WITH A THIN, EVEN COATING OF SEALANT P/N 1052942 (6 MIL TUBE) OR P/N 1052943 (50 MIL TUBE). REFER TO FIGURE 1. DO NOT COVER OR RESTRICT THE GASKET OPENINGS WITH EXCESS SEALANT. MAKE SURE OIL PUMP AND ENGINE BLOCK SURFACES ARE CLEAN AND FREE FROM OIL AND GREASE. 3. INSTALL THE OIL PUMP, AND TIGHTEN BOLTS TO 8 NM (71 LB IN). REFER TO FIGURE 2. 4. INSTALL THE TIMING BELT IDLER PULLEY FOR CAMSHAFTS 3 + 4 AND TORQUE TO 40 NM (30 LB FT). IMPORTANT: THE REAR TIMING BELT COVER AND TIMING BELT ARE NOT INSTALLED AT THIS POINT!

5. INSTALL THE GENERATOR AND TORQUE ITS UPPER AND LOWER MOUNTING BOLTS TO 40 NM (30 LB FT).

6. RE-TORQUE THE SIX (6) OIL PUMP RETAINING BOLTS TO 9 NM (80 LB IN).

7. REMOVE THE TIMING BELT IDLER PULLEY INSTALLED IN STEP 4.

8. PICKING UP AT THE INSTALLATION STEP FOR THE FRONT MAIN OIL SEAL, CONTINUE INSTALLING COMPONENTS PER THE OIL PUMP INSTALLATION PROCEDURE IN ENGINE MECHANICAL SECTION OF THE SERVICE MANUAL. FOLLOW THE PROCEDURE CAREFULLY. BE SURE TO APPLY SILICONE SEALER, P/N 12346286, IN THE TWO PLACES WHERE THE OIL PUMP, ENGINE BLOCK AND OIL PAN HOUSING JOIN TOGETHER (REFER TO FIGURE 3).

IMPORTANT: SEE "TIMING BELT ADJUSTMENT INFORMATION" AT THE END OF BULLETIN.

SECOND DESIGN OIL PUMP AND REAR COVER - ENGINE UNIT NUMBERS 08191279 AND AFTER

1. REMOVE THE OIL PUMP AND GASKET PER THE PROCEDURES IN THE ENGINE MECHANICAL OF THE SERVICE MANUAL.

2. INSTALL THE NEW OIL PUMP GASKET, P/N 90572461. BEFORE INSTALLING THE NEW GASKET, COAT THE PUMP SIDE OF THE GASKET COMPLETELY WITH A THIN, EVEN COATING OF SEALANT, P/N 1052942 (6 MIL TUBE) OR P/N 1052943 (50 MIL TUBE). REFER TO FIGURE 1. DO NOT COVER OR RESTRICT GASKET OPENINGS WITH EXCESS SEALANT. MAKE SURE OIL PUMP AND ENGINE BLOCK SURFACES ARE CLEAN AND FREE FROM OIL AND GREASE.

3. INSTALL THE OIL PUMP, AND TIGHTEN BOLTS TO 8 NM (71 LB IN). REFER TO FIGURE 2.

4. PICKING UP AT THE INSTALLATION STEP FOR THE FRONT MAIN OIL SEAL, CONTINUE INSTALLING COMPONENTS PER THE OIL PUMP INSTALLATION PROCEDURE IN ENGINE MECHANICAL SECTION OF THE SERVICE MANUAL. FOLLOW THE PROCEDURE CAREFULLY. AFTER INSTALLING THE IDLER PULLEY FOR FOR 3 AND 4 CAMSHAFTS, RE-TORQUE THE SIX (6) OIL PUMP RETAINING BOLTS TO 9 NM (80 LB IN). THERE IS A HOLE IN THE REAR TIMING BELT COVER (SECOND DESIGN) WHICH ALLOWS ACCESS TO THE OIL PUMP BOLT BEHIND THE COVER. ALSO, AS SHOWN IN THE MANUAL, BE SURE TO APPLY SILICONE SEALER, P/N 12346286, IN THE TWO PLACES WHERE THE OIL PUMP ENGINE BLOCK AND OIL PAN HOUSING JOIN TOGETHER (REFER TO FIGURE 3).

IMPORTANT: SEE "TIMING BELT ADJUSTMENT INFORMATION" AT THE END OF THIS BULLETIN.

OIL PUMP AND CYLINDER HEAD GALLEY PLUG LEAKAGE CORRECTION

SIMILIAR TO OTHER ENGINES, THE CATERA ENGINE HAS THREADED PLUGS (GALLEY PLUGS) IN THE OIL PUMP HOUSING (REFER TO FIGURE 4) AND IN THE FRONT AREA OF THE CYLINDER HEADS WHICH SEAL VARIOUS INTERNAL MACHINED OIL PASSAGES. IN A FEW INSTANCES ONE OF THESE PLUGS MAY LEAK OIL. TO REPAIR THIS CONDITION, REMOVE THE AFFECTED PLUG USING A 5MM ALLEN WRENCH, APPLY THREAD SEALER, P/N 12346004, AND INSTALL THE PLUG.

IMPORTANT: SEE "TIMING BELT ADJUSTMENT INFORMATION" AT THE END OF THIS BULLETIN.

1ST + 2ND DESIGN OIL PUMP INFORMATION

STARTING WITH ENGINE UNIT NUMBER 08191279, A SECOND DESIGN OIL PUMP HOUSING AND REAR TIMING BELT COVER WAS INTRODUCED INTO 1997 MODEL CATERA PRODUCTION. THE 2ND DESIGN REAR TIMING BELT COVER FEATURES AN ADDITIONAL HOLE WHICH ALLOWS ACCESS TO ONE OF THE OIL PUMP HOUSING BOLTS LOCATED BEHIND THE COVER. SINCE IT IS NECESSARY TO BE ABLE TO RE-TORQUE ALL OIL PUMP HOUSING BOLTS AFTER TIMING BELT IDLER PULLEY INSTALLATION, AN ACCESS HOLE WAS ADDED TO THE COVER TO MAKE THE RE-TORQUE PROCEDURE EASIER. OIL PUMP BOLT RE-TORQUE IS POSSIBLE ON 1ST DESIGN PUMPS AND REAR TIMING BELT COVERS BUT IT REQUIRES THAT THE TIMING BELT IDLER PULLEY BE REMOVED AND INSTALLED TWICE. IT IS IMPORTANT TO RE-TORQUE THE OIL PUMP BOLTS AFTER TIMING BELT IDLER PULLEY INSTALLATION BECAUSE THIS LARGER BOLT TENDS TO PULL THE OIL PUMP TIGHTER TO THE BLOCK AND CAN LOOSEN THE OIL PUMP BOLTS. THE SECOND DESIGN OIL PUMP HAS AN EXTENDED BOSS TO SHIELD THE ACCESS HOLE IN THE REAR TIMING BELT COVER FROM EXPOSURE TO ROAD GRAVEL AND OTHER DEBRIS. IF DEBRIS WAS TO ENTER THE TIMING BELT SYSTEM, MAJOR ENGINE DAMAGE COULD RESULT. BOTH FIRST AND SECOND DESIGN OIL PUMPS UTILIZE THE SAME GASKET. SECOND DESIGN OIL PUMPS CAN BE INSTALLED ON FIRST DESIGN ENGINES, HOWEVER, IT REQUIRES THE USE OF THE 2ND DESIGN REAR TIMING BELT COVER AND THE USE OF A LONGER BOLT (M6 X 25MM) IN THE OIL PUMP HOUSING NUMBER 6 POSITION (POSITION OPENED BY THE ACCESS HOLE IN THE 2ND DESIGN REAR TIMING BELT COVER). OIL PUMP REPLACEMENT IS NOT NECESSARY FOR THE GASKET OR GALLEY PLUG LEAKS DESCRIBED IN THIS BULLETIN.

TIMING BELT ADJUSTMENT INFORMATION

BE SURE TO FOLLOW THE CAM TIMING BELT INSTALLATION AND ADJUSTMENT PROCEDURES IN THE SERVICE MANUAL VERY CAREFULLY. TIMING BELT PROCEDURES AND BOLT TORQUE'S ARE CRITICAL TO PREVENT MAJOR ENGINE DAMAGE. THE FOLLOWING IS EXTREMELY IMPORTANT:

* ALWAYS USE TOOL KIT J-42069 TO LOCK THE CRANKSHAFT AND CAMSHAFTS IN POSITION.

* NEVER USE POWER TOOLS ON TIMING BELT COMPONENTS.

* FOLLOW ALL STEPS IN THEIR PROPER SEQUENCE.

* TORQUE ALL BOLTS TO SPECIFICATIONS.

* USE NEW BOLTS WHEN INSTALLING THE CAMSHAFT SPROCKETS AND THE CRANKSHAFT DRIVE GEAR.

* USE A NEW TIMING BELT IF THE WHITE TIMING MARKS ARE WORN OFF THE ORIGINAL BELT.

FIGURES: 4 ATTACHMENTS: 0

FIGURE 1 - OIL PUMP GASKET (PUMP SIDE) FIGURE 2 - OIL PUMP HOUSING BOLTS FIGURE 3 - OIL PUMP SEALANT APPLICATION POINTS FIGURE 4 - OIL PUMP GULLEY PLUGS

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.

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