rear main still leaking

[89eliminator]

i replaced my rear main seal 3 times in the past month and it still leaks a little bit. i know i am putting it in right. the engine has 135000 miles on it. our cherokee does the same thing and it has 150000 miles. is it just the mileage or am i over looking something.

[speed_racer]

Have you spent the best $9 you ever could on an oil-leaking 4.0? Go to the dealer (specific item) and get an oil filter adapter o-ring kit, lots of times this is the source of this problem, considering you did visual inspection of your pan, and seals before installing, and torqued everything to spec, including a retorque every 2-5 heat cycles for at least 3 times...?!

[jeepthing07]

Could be the back of the valve cover too

[500 MJ]

If you take the old rings in to carquest, they can match them up and it will only run you $1.37... ;) There is one bolt that holds that filter adapter on. Usually the orings are TOASTED...

[Oizarod115]

Could be the back of the valve cover too

yeah, alot of times a valve cover leak can run down that area and look like a rear main.

[Pete M]

I changed my rear main 4 times or so in 2 days. I found that I had to use copious amounts of sealant and then let it sit overnight to cure. Another option I've heard of is the double lip seals (for use when the metal surface is scored). But if you haven't replaced the o-rings or valve cover gasket yet, I'd start there. Dropping the pan sucks.

[Duner]

You definitely are paitent most of us would have gone crazy after changing the seal once.

 

Jus a run down on my 90MJ, first leak fixed was the oil filter and adapter becuase the filter was stuck to the adapter. My dad ended up unbolting the adapter from the block (new o-rings from jeep) and new filter solved that leak.

Next was the valve cover the 4.0 is notorius for this but my dad says all inline 6's have similar problem.

Finally rear main seal as it was begining to look like an alaskan oil spill in the driveway as well as smoking from the oil on the exhaust pipe.

No more oil leaks for a while but it appears the valve cover is starting again.

 

I'm not sure why your leak is still coming from the main - could it be the rear seal on the pan gasket? I remember having to pull the pan down a couple of times because th gasket kept sliding while trying to put the pan back in place. We did opt for Fel-Pro's one piece pan gasket and have had no problems.

[Pete M]

I never said I didn't go crazy.... :D

[Oizarod115]

I never said I didn't go crazy.... :D

 

i thought rear main seal jobs were supposed to be a fairly easy/straightforward project? yall're making me not wanna do mine.

[JeepcoMJ]

the rear main is a PITA because it goes AROUND the crankshaft. to do the one in the 4.0, you have to pull the pan, then you have to pull the seal (I believe it's a 2 piece seal?) the top part of the seal is the worst part as you can't move the crank downwards unless you unbolt the mains, and all the accessories and timing chain. so to get the seal out you have to push up on it then pull it around the top of the crank and downards. then you have to slide the new one in but keep it from getting folded or screwed up in any way. one f*up will screw ya. then you have to put it back together...keep in mind there will still be oil dripping down from the block so you have to wipe down the surface for the pan gasket...and wipe...and wipe...and wipe again, until it's either all out or you just want the damn thing back together.

 

then there's the other type of rear main...the type in my camaro engine. to do THAT type you have to remove the tranny, bellhousing, clutch, and flywheel, and pull it out with a tool, then press in the new one. I neglected to do that one when i built my engine, as i didn't tear down the heads or block, just the intake and oil pan and valve covers. end result; i have 7 to 12 hours worth of work to replace the seal, and do it correctly.

 

not fun.

[rejeep]

if its not leaking from anywhere else but your RMS... you prob scored your crank..

nothing you can do there.

 

your shouldnt need RTV for the RMS.. I have done many w/o a drop and in some cases it leaked after doing it with RTV.

a good tight seal will work with nothing else on it.

 

if you check with the dealer there is no option for a single or double lip seal anymore.. its just one part. Same at autozone, they say they have both in the computer, but only one style in stock..

 

Some RMS will just leak... something you might have to deal with.

My current 4.2L block in my YJ has a prepetual small drip from the RMS.. I have had it done twice by a Jeep expert, once by the dealer and myself.. it still leaks a bit..

park on the street, park on grass, cardboard is your friend..

 

only thing not mentioned is the one peice oil pan gasket.. its a must!

[Duner]

if you have the AX-15 you will probably have to pull your tranny back from the block in order to get the crank to drop down where you can get the upper rear seal into place. Definitely go with the one piece pan gasket.