Exhaust - Smoke on Engine Start Up

91chevy27

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.