Is my rear main seal bad?

rascal · May 22, 2014

I posted pics in the other thread I started; "Pulling a ZF6". Post #58

http://powerstrokearmy.com/forums/showthread.php?t=50559&page=6

If anyone else has ever seen the elusive "bad rear main" please take a look at the pics and let me know what you think.

The seal appears to be in good shape along with the RTV used to seal the rear main to the block. I am starting to think it is the oil pan seal just below the rear main.

Is it common for the pan to leak in the back?

Thanks for any input anyone can offer.

Arisley · May 22, 2014

It is more common for the pan to leak than it is for the rear main to leak.

To replace the pan gasket, the motor has to come out of the engine. The gasket is Ford gray death silicone.

rascal · May 22, 2014

Well, I am not taking the engine out...yet.

I was thinking about trying to put a good bead of RTV between the current bead and rear lip of the oil pan.

I know there are no gaurantees if I do this but hoping it will hold until I can take the engine out.

Tom S · May 23, 2014

THANK YOU FOR TAKING CLEAR IN FOCUS PHOTOS! Way too many user flunk that step.

http://powerstrokearmy.com/forums/showpost.php?p=998544&postcount=58

To me it looks like the pan is leaking not the seal. Interesting how that seal says do not prelube on it.

rascal · May 23, 2014

Thanks! Yeah just wanted someone who might have seen an actual failed rear main to look at these pics to see something I might not. THis is my first time doing this.

I think I am going to goop up the rear seal of the pan until I have the opportunity to redo the entire oil pan seal when I pull the engine.

Edit: I also started thinking it was the oil pan when the flywheel, clutch, & pressure plate had no oil them and were clean. Figured if it was th rear main the clutch assembly would have been throwing oil. Sound right?

Thanks for the input!

Arisley · May 23, 2014

How big of a spot does it leave on the ground?

rascal · May 24, 2014

Arisley said:
How big of a spot does it leave on the ground?

It has been a few drips everytime it is parked but the bell housing was full of oil. It was coming out of all the holes in the bell housing and going all over stuff under the truck while driving.

I was adding .5qt to 1qt every week or two it seemed like.

Arisley · May 25, 2014

Is there any oil in the valley? If so, that is where it is coming from. There is a drain hole in the valley that drains into the bell housing.

rascal · May 27, 2014

Arisley said:
Is there any oil in the valley? If so, that is where it is coming from. There is a drain hole in the valley that drains into the bell housing.

No oil in the valley. Cleaned up all the issues in the valley last year.

However, I do still get a small amout of oil from the turbo pedistal. For some reason I can't get the oil to stop leaking from there