TAIL PIPE SMOKE ON START-UP (INSTALL NEW VALVE SEAL KIT)

SUBJECT: TAILPIPE SMOKE ON STARTUP (INSTALL NEW VALVE STEM SEAL KIT)

VEHICLES AFFECTED: 1987-1991 B, F, G, Y, D CARS AND C/K, R/V, G AND P TRUCKS W/5.0,5.7L -----------------------------------------------------------------------------

THIS BULLETIN CANCELS AND SUPERSEDES PRODUCT SERVICE BULLETIN #'S 89-650-106 AND 89-657-110,90-650-105, 90-657-107. ALL COPIES OF THE ABOVE BULLETINS SHOULD BE DISCARDED.

CONDITION:

---------- Some owners of the above vehicles may comment on a puff of blue or bluish white tailpipe smoke on startup.

CAUSE:

------ Oil leaking past valve stem seals and being deposited on exhaust valve(s).

CORRECTION:

----------- A new valve stem seal kit (P/N 12511890) has been released to address this concern. The kit incorporates a new umbrella seal with a "viton" insert for the exhaust valve stem.

Parts are currently available from CANSPO.

Use applicable labour operations and times.

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.