twintracks

What's the prefered method to get cork gaskets to seal on oil & tranny pans?? Every time I do them, they drip. I know about straightening the pan flanges, and I tighten them to specs, and still they leak. Some say use silicone, others say never use silicone.
Thoughts?? Better sealants?? Tricks?

Thanks, Jerry

Tedd Thompson

Just a thought but are you using synthetic oil? When I did I developed oil leaks. When I went back to non synthetic and lost most of the leaks.

Make sure its the pan that is leaking, I fought the pan gasket and rear main for quite awhile till I found out it was the fuel pump gasket that was leaking. It was very hard to find leaks when the whole bottom of the engine is weeping oil. It helps if you steam clean the bottom so you can isolate exactly where the leak is...Tedd

twintracks

Hi Ted, I was using non detergent oil, straight 30 wt.
Then an old timer suggested I use Penzoil 20-50 racing oil, since it is the only oil still putting in zinc additive for flat, non-hydraulic tappets. ('37 Olds flat eight) I think it is a blend, so you might be right. He also said synthetics leak worse out of seals.
I'll see if it's a blend, and do some more testing & checking.
I'll check the fuel pump gasket as well.

Thanks, Jerry

Fun71

I typically put gasket sealer on one side of the gasket, lay it on the pan, then set the pan on a flat surface (gasket side down) and let the sealer cure and "glue" the gasket to the pan. After it's set, I apply sealer to the other side of the gasket, install the pan, and tighten the bolts, starting with the middle bolts and going outward, alternating from one side to the other as I go around the pan. My sealer of choice is typically blue RTV.

Tedd Thompson

Here is a link on what I feel is the straight skinny on oil. I use Rotella T but there are others out there that are zinc rich and test higher on their stress test and aren't diesel or racing oil plus don't over do it with zinc. Its a long read but I found it informational and disproves many myths....Tedd...http://540ratblog.wordpress.com/

Fun71

Interesting info. Thanks for posting that link as I am always interested in learning about things I previously knew nothing about.

Don R.

I'm sure many will disagree but I never use RTV or silicone as gasket sealer except for the junctions of intake manifold side and end gaskets where they are separate pieces. RTV was designed to replace gaskets not glue them in place. For pan gaskets that are not coming off anytime soon I use Permatex High-Tack on one side and Permatex No. 2 on the other, let the high-tack set up a little then bolt it up. On things like valve covers that might need to come off use high-tack on the cover side and coat the other side with a thin layer of wheel bearing grease. The big trick with pans and sheetmetal valve covers is getting the gasket flange straight. Most of the time the bolts have been overtightened and the flange is wavy which creates leaks. Use a hammer and a flat surface to flatten the bolt hole areas and check with a straightedge, then follow the torque specs and retorque from time to time.

TripDeuces

http://lubelocker.com/collections/transmissions/gm

Best gasket I ever used.

twintracks

Don,
Thanks for your input. I'll give that a try on my next project.
Thanks, Jerry