can't stop oil pan leak!

[Jack O.]

I need some help. I've tried several times to fix an oil pan leak without success. I know its leaking between the pan and the rear main bearing cap and that it is not the rear main seal leaking. I have a '69 427/435 with the original oil pan. I've removed the pan and did some minor straightening but it really didn't appear to be terribly out-of-whack, especially in the area that goes around the rear main cap. I used the expensive one-piece Fel-Pro #64018 "PermaDryPlus" gasket and carefully torqued the pan to spec's.

I don't want to do this again so I'm thinking about buying a new oil pan and trying again. Should I replace the oil pan? If so, do I just get the current offering from GM or is their a better choice? Any other suggestions?

Thanks!

[Clem Z.]

Re: can't stop oil pan leak!

make sure the leak is not the joint between the the rear cap and the block because if the proper sealing method was not used on the rear cap the rear crank seal may not be leaking but this interface could.

[Joe L.]

Re: can't stop oil pan leak!

Jack-----

I agree with clem; usually these "REAR oil pan leaks" are actually caused by the rear main seal, whether or not it appears that they are. As clem says, proper installation of the rear main seal is absolutely critical if a leak is to be avoided. A few areas of particular concern:

1) sealer must be applied to the areas on either side of the seal as shown in the chassis service or overhaul manual. Failure to do this or failure to do it properly WILL result in a leak;

2) if the crank's journal surface that the seal rides on is worn or damaged in any way, it WILL result in a leak. If this is present, you MAY be able to salvage things by using a special seal with an off-set lip;

Actually, I really doubt that you need a new oil pan and if you've used the Fel-Pro 1 piece gasket, then you've used the best there is. It should seal unless there is obvious damage or distortion to the pan.

If you do decide that you want to try a new oil pan, the current GM SERVICE replacement, GM #14091356, is the best pan to use. It's virtually identical to the original except for spot welded-on corner reinforcments. These can be obtained in reproduction and added without need to spot weld them.