Valve Cover grommet part numbers

[Keith M.]

So here is nitty gritty question. Car is a late 1969 L46 4spd with aluminum valve covers. I have seen "NOS" valve cover grommets #3994239 and #3989349. Is either of these original part? Both service replacements? Or....?

GM Parts Wiki continues to be "flaky" for me...lots of timeouts etc.

Thanks in advance.
Keith

[Joe L.]

Re: Valve Cover grommet part numbers

So here is nitty gritty question. Car is a late 1969 L46 4spd with aluminum valve covers. I have seen "NOS" valve cover grommets #3994239 and #3989349. Is either of these original part? Both service replacements? Or....?

GM Parts Wiki continues to be "flaky" for me...lots of timeouts etc.

Thanks in advance.
Keith

Keith------


Well, considering that both GM #3994239 and GM #3989349 didn't even exist during the 1969 model year, it's not very likely that either were original for the 1969 L-46 application. Even the predecessor of the 3994239 was not applicable to the 1969 L-46 application and the 3989349 had no predecessor part. However, a predecessor to the 3994239 was used for 1969 with 300HP and either the 3994239 or its successor, GM #14091870 can be used for replacement for the 300 hp application.

The original grommets used for both sides of the L-46 application were GM #3946862. The latter was discontinued in December, 1971 and replaced by GM #3989348 which continues to be available from GM to this very day. The 3989348 is virtually identical to the 3946862 and I do not think that any difference is discernible when installed on the valve covers.

Below are photos of the 3989348:

GM#3989348(a).jpgGM#3989348(b).jpg