• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Oil Pan Blues

Tony_SS

NAXJA Supporting Vendor
Location
Washington MO
My oil pan loves to leak right after I park and turn off the engine for some reason... a 3-4" puddle and then it seems to stop?

I don't get it.

I'm going to drop the pan.... what would you do to seal it up? I have a rubber Fel-Pro gasket installed dry right now.
 
Are you sure it's the pan?

There are several other suspects that can produce what LOOKS like an oil pan leak or an RMS leak. Notoriously, a valve cover gasket, an oil filter adapter leak...and an RMS leak.

The drip stops after awhile because there's no oil "reservoir" except the pan and usually all the oil drips down to the bottom of the pan...so no more oil available to leak.

Unless your CERTAIN that the oil pan gasket is leaking, you'd do well to clean the engine off, drive it around the block and see where the leak actually is coming from. Then do what is needed to fix it.
 
Unless it's leaking from the very back of the valve cover, the rest is bone dry. As is the oil filter adapter/area...what is RMS?

Odd thing is a I have oil that will drip from a few mounting studs..but I dont see any signs of it coming to the stud..it looks like it comes from behind it.
 
RMS = Rear Main Seal.

Exactly where "under" the pan does the puddle form? Front, back, drivers side, passenger side, at a specific corner, under the drain plug?
 
Hope this provides some clarification:

 
I'd be looking up ABOVE first, and VERIFYING the source of the oil leak YOURSELF.
Everybody, who doesn't own or have to pay for or perform your vehicle repairs, loves to poke their noggin UNDER the Jeep and come out bearing the false bad news that your RMS is leaking.
Many mechanics, friends, people on Jeep forums who can’t see your Jeep from where they’re at, and good old Uncle Bob seem to enjoy telling you it’s the rear main seal. Has a catastrophic ring to it, doesn’t it?
A simple leak at the back of the valve cover or other source could produce the same symptoms. You don’t need to be a mechanic to figure this out. If you have good eyesight and a dim flashlight, you’re good to go on your own. Don't jump on the RMS/oil pan gasket bandwagon right off the bat.

Almost any oil leak on your 4.0 is gonna drip from the RMS area for two simple reasons.
First off, the engine sits nose-up and any oil will run back to the RMS area. Secondly, the RMS area is also the lowest point on the engine. Simple physics and the old plumber's adage apply here. "$hit flows downhill".

Valve cover gasket, oil pressure sending unit, oil filter adapter seals and distributor gasket, in that order, have to be eliminated as possibilities first.
Revised 02-26-2013
 
Unless it's leaking from the very back of the valve cover, the rest is bone dry. As is the oil filter adapter/area...what is RMS?

Odd thing is a I have oil that will drip from a few mounting studs..but I dont see any signs of it coming to the stud..it looks like it comes from behind it.

My experience with the valve cover is that the last bolt at the rear of the head is difficult to reach...and to tighten. It doesn't need to be super tight, but it does need to be snug. Also when installing the VC that's exactly where it'll leaks from as it is in a tight spot and hard to get perfectly lined up...especially if you have a cork gasket.
 
My experience with the valve cover is that the last bolt at the rear of the head is difficult to reach...and to tighten. It doesn't need to be super tight, but it does need to be snug. Also when installing the VC that's exactly where it'll leaks from as it is in a tight spot and hard to get perfectly lined up...especially if you have a cork gasket.

Gotta have that felpro blue, baby!!!!!!
 
Are you sure it's the pan?

There are several other suspects that can produce what LOOKS like an oil pan leak or an RMS leak. Notoriously, a valve cover gasket, an oil filter adapter leak...and an RMS leak.

The drip stops after awhile because there's no oil "reservoir" except the pan and usually all the oil drips down to the bottom of the pan...so no more oil available to leak.

Unless your CERTAIN that the oil pan gasket is leaking, you'd do well to clean the engine off, drive it around the block and see where the leak actually is coming from. Then do what is needed to fix it.

You left off the DISTRIBUTOR gasket. Oops--Cruiser54 got it.

Also, the head can seep oil along the right (passenger) side of the engine.
 
Absolutely clean the engine first! The pan and valve cover gaskets are easy. Make sure everything is clean and dry and I use Blue RTV for everything in contact with engine oil. The pan install is easy if you use studs for alignment. Cut the head off some 1/4" bolts and taper the non threaded end. Screw them into the block, put the gasket up there and then the pan. The rear main is easy too but the upper seal can be stuck. I worked some WD-40 around it using a pick to move the seal a bit. Be careful not to scratch the crank. My seal broke loose after a few minutes. Once again clean and dry and put a 1/4'' daub of RTV where the RMS meets the pan gasket. This is also a good time to inspect rod bearings. After doing all the above, I can now park in my Dad's drive way and not leave a drop. Good luck and take your time. Oh yeah, I had to support the frame and take my tires off to drop the axle enough to drop the pan.
 
Once again, thanks to the excellent advice here, I reached behind the VC and felt a bunch of oil on the back of head. Yes! So I'm hoping that is the main source of the oil leak. I'll snug it down a bit more back there and hope that does the trick. Yes I used a blue Fel Pro too...but its an Dorman valve cover to it probably needs a bit more torque to fit correctly. THANKS all. Once I get the leaks fixed it's build thread time.

I installed the VC gasket dry and only used Motobond on the corners of the RMS.
 
Dorman.. their parts are hit and miss at best.

On the RTV and oil pan gasket, just in case you still have a leak, the new gaskets don't have the little ears that fit into the recesses on each side of the main cap. You need to fill those recesses with RTV. Also you should put some at where the gasket meets the timing cover. Usually not necessary though ad the fit of the timing chain cover is pretty good.
 
Yep I have a 2001 block so I filled the ears with MotoSeal and I think I'm good on the RMS.

I pulled the VC and put MotoSeal around the back..under and above the Fel Pro gasket...I snugged the rear 4 bolts down under I couldn't anymore by hand. I did the rest about 12lbs... I'm pretty sure its good... I'm not crawling under but I don't see any drips.

Thanks all. Build thread time.
:cheers:
 
Back
Top