Oil Leak

[Gas Pumper]

Hello all, first post here.

Yesterday, I bought my first FSJ, a 1981 Wagoneer. It has a 3 speed auto, a 360 V8 and is part-time 4x4. I wanted one of these things for so long, and I finally found this one for an awesome deal.

I have tried using the search function, and have had some luck with the problem it has...

This thing has a MASSIVE oil leak. We are talking a quart every 20 miles or so. I did a little looking around and its all coming from the back of the motor. It drips down from an unknown source to the transmission bellhousing, which then leaks on the exhaust crossover pipe, resulting in the Jeep's self activating smoke screen of blue.

I have no idea where it's leaking from, but some research on this forum has shown that the likely culprit is the valve covers. However, I think that's a lot of oil from a valve cover leak. I'm inclined to think its the rear main seal because of the amount thats pouring out, or some comination of valve covers and RMS.

Any insight to what the problem is? I would provide some pictures, but I just can't see behind the engine well enough.

Thanks in advance!

EDIT: I didn't realize I posted this in the wrong forum, I apologize! I don't want to double post, can someone move it to tech?

[Knuck]

A quart every 20mi is a bit much for a valve cover leak imo. If it were me I would go straight for the rear main seal.

[Gas Pumper]

That is what I was thinking too. The RMS is accessible by dropping the oil pan, right?

Any other ideas?

[Knuck]

I've never had to replace mine (furiously knocking wood)....yet, but yes. Do a search on replacing the rear main seal and should should get plenty of hits. It can be kind of tricky as you dont want to nick the seal at all.

[jeepjseries]

i second that it is the rear main seal

[vintagetrks]

I also agree with the rear main seal theory. If your not comfortable with dropping the pan and replacing it (replacing an RMS can be frustrating) as mentioned before you Do Not want to nick it or it will leak. Take it to a reputable shop and have it replaced. No more leak. :)

[Gas Pumper]

I also agree with the rear main seal theory. If your not comfortable with dropping the pan and replacing it (replacing an RMS can be frustrating) as mentioned before you Do Not want to nick it or it will leak. Take it to a reputable shop and have it replaced. No more leak. :)

I see that you are local to the Prescott area. Any reputable shops around here?

[newtojeeps]

check for crushed tail pipe, plugged muffler. Could be blow by.

[Gas Pumper]

check for crushed tail pipe, plugged muffler. Could be blow by.

The exhaust system is in good shape.

[FSJ Guy]

Sure sounds like a rear main seal. An easy job by the 3rd or 4th time you've done it! LOL!

Hit your exhaust Y-pipe bolts with PB Blaster well before you have to remove them (most of the time you have to drop the Y-pipe to have access to the rear main seal).

It'll cost at least $400 or so for a shop to do it because of the labor. If your time is short, it's worth it. Otherwise, plan for a weekend to do it the first time. The seal comes with instructions. Follow them. :D

[brtisch]

Good Possibility it's the RMS, but also check the rear of the intake manifold. I've seen one that had a leak coming from the front and/or rear of the intake at the end seals. Looks like the PO tried to re-seal and used the rubber end seals which resulted in a leak...about a quart every 50 miles or so. It dripped down to the exhaust as well and got the nice smoke coming out he rear on the highway. Easier fix than the RMS and something to check out.