Marty Snip I have lost two of the push in type oil filler caps from my daughters aluminum valve cover in the last couple of weeks. Snip This is a GM part. It was used by Jeep on the Buick V6 based engine Jeep used for a while, common on all other GM cars and should be easily available from an auto parts store. When bought from a specialty company it would have a chrome hat on it to look good. I use them to mount smog parts on Chrome (cheap or inexpensive) valve covers by coring a hole in them to mount the smog fittings when I used them on AMC I-6 engines. Snip I assume it's some sort of pressure build up but what can I do to relieve it? It has the pcv filter at the front of the cover that goes into the carb and the hose that runs from the reor of the valve cover into the air cleaner. Snip It would seem to me you would have to have some serious blow by to generate pressure under the valve cover. The fitting in back is a 3/8 or so hole and sucks clean air into the engine for PCV functioning through a little square filter inside the air cleaner. Usually if you have a pressure problem you have serious blow by and you start blowing oil up into the air cleaner through that fitting and the engine smokes a lot. In addition, if the PCV valve will rattle it is probably open too, as that fitting goes up into the snorkel of the air cleaner there is no real vacuum there, but if there is enough blow by to overcome the size of the hole in the pcv valve and the fresh air vent, there should be some serious blow by visible plus the car smokes a lot. Or That rubber plug thing has soaked enough oil into it that the rubber has deteriorated and it will just skootch itself out of the mounting hole in the top of the valve cover and you are replacing it with equally deteriorated used pieces and they aren't any better than the one you were or are using. Anyway that is what I have found I have to do every now and then. Just replace the equally oil soaked rubber oil cap with a new one that ain't oil soaked. John -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.amc-list.com/pipermail/amc-list/attachments/20070304/408fd660/attachment.htm _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://www.amc-list.com/mailman/listinfo/amc-list