Author Topic: Oil cap/breathers for vortec/centerbolt valve covers:  (Read 4251 times)

Offline Stewart G Griffin

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Re: Oil cap/breathers for vortec/centerbolt valve covers:
« Reply #15 on: September 02, 2018, 08:02:20 PM »
REVISITED:



Can i get some part #'s   for the grommets and oil caps and breathers?

1) Would prefer an oil fill tube with cap, but would settle for just a cap.

2) Would prefer OE, but would consider high-quality aftermarket-----Dorman is probably ok,   K+N, Trans-dapt probably better.......

So, this is for 87 and up vortec valve covers.

Thanks.

Offline Stewart G Griffin

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Re: Oil cap/breathers for vortec/centerbolt valve covers:
« Reply #16 on: January 03, 2019, 06:05:33 PM »
Shameless, self-centered, superbump  ;D


Actually it IS shameful that it's taken this long to try to solve this problem.  Yes, the truck runs but it's apparently leaking oil onto the valve cover.  :-[


(Still using the original grommets and oil fill tube from 86............)

Offline Stewart G Griffin

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Re: Oil cap/breathers for vortec/centerbolt valve covers:
« Reply #17 on: January 09, 2019, 02:11:40 AM »
This stupid problem has really been bugging me and taking WAY too much time and i wanted to get to the bottom of it once and for all.   If it was a few drops leaking, i wouldn't care, but this is too much.   So i took the old grommet out and measured the hole with some calipers.   The grommet itself may not be leaking, but i'll address this as the problem gets solved.


So, for anyone who gives a plop:

To the best of my knowledge so far:

1) The oil fill /oil cap hole for "swirl-port"/"vortec"/ center bolt valve covers up to 93 at least, (so that's 86-93) are the same size for v-8's and v-6's.   i DO NOT know about after 94 at this point.

2) The inside diameter size of this hole is 30.6 mm OR 1 and 3/16" inch.

3) To the best of my knowledge, the correct grommet for this hole is GM part #  10108402  (which replaced old part #3982983)

Some pics:

https://www.ebay.com/p/GM-3982983-10108402-chevy-GMC-350-5-7l-Engine-Oil-Fill-Tube-Valve-Cover-Grommet/655694226

https://www.summitracing.com/parts/nal-10108402