V 10 P/U 4WD V8-350 5.7L (1987)
Valve Guide Seal: All Technical Service Bulletins
Exhaust - Smoke on Engine Start Up
Number:
91-449-6A
Section:
6A
Date:
NOV. 1991
Corporate Bulletin No.: 136007
ASE No.: A1, A8
Subject:
TAILPIPE SMOKE ON STARTUP
Model and Year:
1987-91 CAPRICE, CAMARO AND CORVETTE WITH 5.0L AND 5.7L ENGINES
1987-91 C/K, R/V, G AND P TRUCKS WITH 5.0L AND 5.7L ENGINES
THIS BULLETIN CANCELS AND SUPERSEDES DEALER SERVICE BULLETIN NO. 89-314-6, DATED JULY 1990 AND 90-300-6A, DATED
JULY 1990. THE CAUSE AND CORRECTION HAVE BEEN REVISED. ALL COPIES OF 89-314-6 AND 90-300-6A 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 GMSPO.
Use applicable labor operations and times.