For 1990-2009 cars

# INFORMATION ON SUPERCHARGE ASSEMBLY OIL WEEPAGE

#### SUBJECT: INFORMATION ON SUPERCHARGER ASSEMBLY OIL WEEPAGE

#### MODELS: 1992-94 BUICK PARK AVENUE 1995 BUICK RIVIERA 1992-94 OLDSMOBILE NINETY EIGHT 1992-94 PONTIAC BONNEVILLE EQUIPPED WITH 3.8L ENGINE (VIN 1 - RPO L67)

A SMALL AMOUNT OF OIL WEEPAGE THROUGH THE FRONT SEAL (BEHIND THE PULLEY) OF THE SUPERCHARGER ASSEMBLY IS A NORMAL CONDITION. THIS OIL WEEPAGE IS CAUSED BY MINUTE TRACES OF OIL ESCAPING AROUND THE SEAL DUE TO NORMAL PRESSURE BUILD UP IN THE OIL CAVITY WITHIN THE SUPERCHARGER ASSEMBLY. THE SUPERCHARGER IS FACTORY FILLED WITH 145 CC'S OF OIL. TESTING HAS INDICATED THAT LESS THAN 1 CC OF OIL CAN CAUSE A THIN FILM OF OIL TO BE SPREAD ACROSS THE FULL LENGTH AND WIDTH OF THE SUPERCHARGER CASE. A BUILD UP OF BELT DUST AND/OR AIRBORNE DUST CAN THEN ADHERE TO THE THIN OIL FILM, CAUSING THE OIL WEEPAGE TO APPEAR WORSE THAN IT REALLY IS. FACTORY TESTING HAS PROVEN THAT THIS SLIGHT AMOUNT OF OIL WEEPAGE HAS NO NEGATIVE SHORT-TERM OR LONG-TERM EFFECT ON SUPERCHARGER DURABILITY AND, THEREFORE, THE SUPERCHARGER ASSEMBLY SHOULD NOT BE REPLACED DUE TO THE WEEPAGE DESCRIBED. IF SUPERCHARGER OIL IS VISUALLY DRIPPING OR PUDDLING FROM THE SUPERCHARGER FRONT SEAL, HOWEVER, THE SUPERCHARGER ASSEMBLY WILL NEED TO BE REPLACED USING PROCEDURES OUTLINED IN THE APPROPRIATE REPAIR MANUAL.

FIGURES: 0

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.

COPYRIGHT 1994. GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.