TedH

I've installed and removed my one-piece Fel-Pro blue oil pan seal probably 5-6 times since installing the first pan 10 years ago. When I was setting up the pan with my recent cam swap, I probably removed and installed the pan 3-4 times.

I'm asking as I have a troubling leak that appears to be coming from the area of my rear main seal. The oil is coming down between the oil pan and the trans converter cover. Some even comes out of the converter pan drip hole. I've swiped the oil and it is definitely fresh engine oil. Before the cam swap, I did not have an engine oil leak. I also had the old oil pan.

With the swap, I also installed a new Transdapt OEM replacement oil pan. I noted that I had to torque the pan down before it would rest on the engine rails. I assumed it was because I was pressing the fat front seal loop into the underside of the timing cover and the rear loop into the groove over the rear main cap.

Also, I am running 5W-30. Too thin for my Gen 1 seals? It drips about once every 30 seconds once I park it. It drips for about 20 minutes. I bet it is dripping the entire time I am driving; perhaps more frequently in the hills. I've never run anything thinner than 10W-40 before this roller cam swap.

Could my 1-piece pan gasket be bad? I am losing about 1/2 quart with every trip and I don't trust the vette for more than a couple hours of driving.

7T1vette

Did you put a dab of black RTV in the joints between pan rail and bearing blocks? Fel-Pro may say it's not necessary, but....

I'd say that gasket will be good for as long as it remains "damage-free".

TedH

I thought that was the reason for 1-piece (no more dab of RTV where the rail gaskets met the rubber strap seal).

May be time to for a new 1-piece oil pan seal.

REELAV8R

Rear main seal?

TedH

I hope not. I don't relish pulling this engine again so soon.

01mikep

I use one piece pan gaskets but still put a dab sealant on the timing cover meeting point as well as the rear. If it is the rear main seal, you can do that in the car pretty easy...joy of a two piece seal.

7t9l82

i know your supposed to be able to re use those gaskets, but pardon me if i never do. and i know people who have had to silicone the crap out of the ends, may be the pans fault too

TedH

Don't you have to drop the crank shaft to remove the two halves of the rear main seal? If so, that would also mean I have to disconn all rods/caps from the crank and then lift it back into place.

I've read that if the engine continues to drip oil AFTER being shut off (as mine does) it is most likely the pan/pan seal. I will try the 1-piece pan seal first to see if that solves it. It drips for about 30 minutes. I've checked the oil pressure sender at rear of intake and it is dry and no oil running down the back of the block (it is dry). Also, no oil coming from rear intake seal.

bpassmore

I too use a dab of silicone at the ends. Aftermarket pans seem to leak.
To replace the rear 2 piece seal, loosen the main caps the shaft will drop slightly, the upper seal then can be pushed out. About a turn and 1/2 on the main bolts should be enough. Use the guide furnished with the seal kit to guide the upper seal.

TedH

I'll go with new 1-piece pan gasket and dab of silicone at the corners to see if that solves it. Hope so.

REELAV8R

I hope that is the problem also for your sake. I would think it drips for a period of time simply because the flywheel guard has oil in it and it takes a while to all run down and drip out the small drain hole.
I just had to replace my rear main twice, long story. You don't have to loosen any of the mains except for the rear one holding in the seal itself. That one you have to remove the lower shell half and then push out the upper half of the seal.

TedH

Good info. Thanks for sharing. Will advise once I install the new pan gasket with dabs of silicone at corners.

dmaxx3500

rear main seals are NOT re-usable,and everything gets silicone seal put on it

7T1vette

In general, silicone is a poor sealant to use with oil/gas. That's why folks stick their outside mirrors in gasoline overnight to break the mirror free from the support posts (silicone adhesive).

The only silicone product that is made to work with petroleum products is RTV black. It is the ONLY one to use for engine gasket sealants. There are other types of sealants that will do fine...but only RTV black, if you want silicone.

TedH

Understood. I have reused the 1-piece Fel-Pro oil pan seal. Rear mains/seals has not been touched since '99 rebuild. I will use the silicone seal at corners of the rear 1-piece pan gasket when I install it.

TedH

Glad to hear that. I have a tube of black rtv from my intake/cylinder head install (used on bolt threads and at corners of intake gaskets). I will use it.