Don 68

I'm having problems sealing a leaking oil pan on a 1968 327 engine. This is a new rebuild and the leak is at the back of the oil pan where the pan has the rubber gasket. I used the four piece gasket set and sealed it in the four corners as recommended. It looked like it leaked between the pan and the gasket at the bottom of the dip in the pan. I drained the oil, cleaned the pan and block, checked the pan for straightness and tapped the holes with a ball peen hammer to flatten them. I was told the oil isn't coming from the rear main seal as it is not getting on the flex plate and slinging oil. It drips about 10 drops per minute and only when the engine is running and warmed up. I decided to use a one piece Fel Pro gasket and it still has the same leak in the same place. I removed this gasket and put sealant between the gasket and pan where it leaked to seal it up. I know directions says to only use sealant in the four corners and install dry but I had to try. It still leaks the same. What should I do? Right now the engine is on a test stand andI need to get this done and engine dropped into frame so I can start on the body.
Thanks, Don

DUB

You are aware that there are more than one design of oil pan gasket for an oil pan. when the pan is off...and you set it on a flat surface....and measure the highest point in the rear seal area...the distances can be different. I ran into this issue and needed a different gasket. They are not that much different...but enough to cause it to leak a lot when running..

Also....you can apply some soft modeling clay on the rear main seal cap area...then install the pan with some oil on the surface so it will not stick to the clay..or use a small piece of Saran Wrap......and then pull it and see how much gap you actually have.....then contact Fel-Pro.

DUB

DUB

Here... check this out.

https://www.corvetteforum.com/forums...-question.html


DUB

forvicjr

To properly seal the pan you also must apply sealer between rear main and the block. This is the most common mistake people make. Also you can gently tap the lips of the pan towards the block after installation to further tighten this area also. The best pan gasket for people that dont install a lot is the one piece felpro part. The rear main will seep oil between the block and main and run down to the lip of pan and make the pan gasket look like the culprit. I also offset my rear main seal. Some dont and just apply sealer to the ends during install. $0.02 deposted. Hope thos helps..

19LEW71

http://www.summitracing.com/parts/fe...make/chevrolet
NO MORE OIL PAN LEAKS (make sure this is the correct one)

Don 68

Thanks guys,

Dub, the distance is 2-1/4" so I think I bought the right Fel-Pro one piece gasket. I will do the clay test and see how much clearance i really have. I'll have to do this when I get back from the Charlotte Auto Fair.

Forvicjr, when I removed the Fel Pro gasket I saw traces of oil between the gasket and oil pan. I did not see any oil between the gasket and block. I will try to tap the lip to see if that stops it. (good tip) I didn't offset the main seal but I did put sealant in the corners. I could offset the seal just to make sure.

19lew71- I did use the Fel Pro gasket after I first used the 4 piece gasket set. Still leaked. I believe it was the correct one as it is the old style with the thin gasket. I think it was the mid 70's when they used the thicker seal.

Scottd

Without wasting a bunch of time on what everyone else has said.....you need to go to the Felpro 1 piece.

Hey, is Tapco still in your neck of the woods?

Don 68

Scottd,
I used the four piece gasket the first time I tried to seal it then I used the 1 piece Fel Pro and it still leaked. Who is Tapco?
Don

Don 68

The problem wasn't in the gaskets at all. When I installed the rear main seal during the rebuild I had inadvertently turned the bottom half of the seal around 180 degrees. Half of the seal was facing correctly and the other half wasn't. All fixed now and no leaks anywhere. (I reused the one piece seal). I can now install it in the completed frame, push it to the side and start on restoring the body. I'll add some pictures in a few days as I know a thread is worthless without them.
Don