For 1990-2009 cars

# INFORMATION ON CAMSHAFT HOUSING ASSEMBLIES

REVISION: 02/15/95

THIS BULLETIN IS BEING REVISED TO ADD A CLARIFICATION PARAGRAPH AT THE END. ----------------------------------------------------------------------

#### SUBJECT: INFORMATION ON CAMSHAFT HOUSING ASSEMBLIES

#### MODELS: 1988-94 BUICK SKYLARK 1990-94 CHEVROLET BERETTA 1992-94 OLDSMOBILE ACHIEVA 1987-91 OLDSMOBILE CUTLASS CALAIS 1990-91 OLDSMOBILE CUTLASS SUPREME 1988-94 PONTIAC GRAND AM 1990-91 PONTIAC GRAND PRIX WITH THE 2.3L ENGINE (VINS A, D, 3 - RPOS LG0, LD2, L40)

ALL 1987 THROUGH 1993 QUAD-4 CAMSHAFT HOUSING ASSEMBLIES ARE SERVICED WITH A 1994 MODEL CAMSHAFT HOUSING ASSEMBLY.

THE 1987 THROUGH 1993 HOUSINGS HAVE A SEAL GROOVE IN THE HOUSING. THE 1994 HOUSINGS HAVE A SEAL GROOVE IN THE COVER. THE SEAL GROOVE IN THE 1994 COVER IS DEEPER THAN THE SEAL GROOVE IN THE 1987-93 HOUSINGS. IF A 1987-93 SEAL IS USED IN THE 1994 HOUSING ASSEMBLY, THE COVER GASKET WILL LEAK. IF A 1994 SEAL IS USED IN A 1987-93 HOUSING ASSEMBLY, CAMSHAFT JOURNAL CLEARANCE AND SEAL LIFE COULD BE AFFECTED.

ORDER A 1994 CAMSHAFT HOUSING ASSEMBLY SEAL IF A 1994 HOUSING IS ON THE ENGINE.

FIGURE 1 SHOWS THE 1987-93 VERSION OF THE CAMSHAFT HOUSING TO COVER SEALS. 81A SEAL, INNER (EXHAUST, RED) 81B SEAL, OUTER (EXHAUST, RED) 81C SEAL, OUTER (INTAKE, BLUE) 81D SEAL, INNER (INTAKE, BLUE) 90 HOUSING, CAMSHAFT - GROOVE IN HOUSING

FIGURE 2 SHOWS THE 1994 VERSION OF THE CAMSHAFT HOUSING TO COVER SEALS. 81A SEAL, INNER (EXHAUST, RED) 81B SEAL, OUTER (EXHAUST, RED) 81C SEAL, OUTER (INTAKE, BLUE) 81D SEAL, INNER (INTAKE, BLUE) 90 COVER, CAMSHAFT HOUSING - GROOVE IN COVER

THE 1994 CAM CARRIER COVER SURFACE THAT SEALS AGAINST THE HOUSING IS NOT A MACHINED SURFACE. THE SURFACE IS DESIGNED TO BE AN "AS CAST" SURFACE AND THE UNMACHINED SURFACE WILL NOT CAUSE A LEAK.

FIGURES: 2 ATTACHMENTS: 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 OCCURRING 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 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.