So I've got a leaking rear main seal. Spoke to a mechanic who owns his own cherokee and he said you cant completely stop a rear main seal from leaking, that you can only slow it down. I find that hard to believe. Wouldn't they have done a recall on the cherokees if that was the case? Should I trust this guy? I just bought a nice 1992 cherokee and if it's going to continuously leak I'll probably get rid of it. If what he said isn't true then maybe I shouldn't have him work on it? Any info would be great

 

Inspect the contact surface on the crank. If there's damage there might be a problem. Otherwise, select a slightly improved seal like Fel-Pro BS40612.

 

I dont think I would speak to that "mechanic" ever again...

 

That depends on what he meant. He probably meant, "there are no shortcuts that will stop the leak. It has to be replaced." If that's what he meant, it's not time to fire him.

If what he meant is, "it can't be fixed by any method. You must live with it forever", then, yes, fire him.

I'm pretty sure he meant there are no shortcuts.


However, before you dive into replacing the seal, give some AT-205 a shot. It's cheap, and it often works spectacularly. Sometimes it doesn't work at all. It depends on the reason for the leak and the seal material, I think. I used it to stop a gusher of a front main seal leak on a Ford 351. It slowed to a very tolerable trickle. I used it to completely stop a power steering pump leak on my Cherokee. I used to to.... do not much on a Cherokee trans leak. And I used to to noticeably slow down a trans leak on another Cherokee.

But for around ten bucks, it's worth a shot.

 

[QUOTE=Dave51;3589930]Inspect the contact surface on the crank. If there's damage there might be a problem. Otherwise, select a slightly improved seal like Fel-Pro BS40612.[/Quote

Where is the contact surface on the crank? Have to remove the oil pan to view that?

 

All you need to know about RMS replacement:


At 6:40, see the contact surface of the seal on the crank.

 

thanks!

Any write up or video on how to remove the axle and jack the car up like that? I'm thinking I need to fix this myself because I dont have access to a truthful mechanic

 

You don't need to do that (that poster is a suspension guy, so no matter what he does he takes the axles out first).

You only need to remove the starter, exhaust downpipe and jack up the body of the vehicle to allow the front axle to droop.

Consider slapping in a new oil pump while you're in there.

 

Although you only got about 70K on that thing?

BTW did you fix the fuel pump?

 

didn't replace the fuel pump yet. Haven't been driving the jeep because of the leaks. Wanna get those fixed first.

Okay great so I dont need to remove the axle. How do I Jack up front end so I dont kill myself? What kins of jacks/ stands do I need and where do I place them, what safety precautions should I take ?

 

I use 2 garage jacks and 2 jackstands on the unibody (since you need to droop the axle). Since you'll still have the tires on, if the jeep falls off you won't get crushed (fatally)(probably).

 

thanks. Will go pick up jack stands and a floor jack later. What is the best oil pan gasket and rear main seal available on the market?

 

Have you absolutely indentified this as a rms? A leaky valve cover gasket at the back of the motor will do this, the o rings at the oil adapter will cause this effect. I have done this repair in the last 6 months, and I would positively identify this first. This repair is not as easy cut and dry as shown, takes time, dedication, and patience. I did not have to replace my rms until 318,000,...just saying. Also there is a great write up by crusier54 about oil leaks, check that out first before just diving in.

 

YES!!!! THIS!

Can't believe it took this long for someone to point this out! Guys, you're slacking!

 

If you are thinking Harbor Freight, go with the 6 tons. Their 3 tons are pretty flimsy.


It's hard to go wrong with FelPro.


Okay, Dave, I'm picturing oil changes here....