Oil leak??!!!
08-02-2019, 04:40 AM
#1
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Location: Zebulon nc
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Year: 1997
Model: Cherokee (XJ)
Engine: 4.0
Oil leak??!!!
I know this is been beaten to death over and over but I am truly stumped and I'm losing my patience. Have a 97 XJ with this straight 6 and an automatic transmission. I have an oil leak that is driving me nuts it leaks all over my exhaust and my tranny pan. All over my bell housing.
With that being said I'll tell you what I've replaced already I have replaced the oil pan gasket the rear main seal the oil filter adapter Seals and the transmission pan gasket.
It doesn't look like the oil is coming from my oil pressure sensor unit I guess it could possibly be coming from the back of my valve cover gasket but there are no signs of it if y'all could enlighten me to your past experience and help a brother out before I sell this thing and I don't want to do that because I do love it but I'm sick of dealing with it
With that being said I'll tell you what I've replaced already I have replaced the oil pan gasket the rear main seal the oil filter adapter Seals and the transmission pan gasket.
It doesn't look like the oil is coming from my oil pressure sensor unit I guess it could possibly be coming from the back of my valve cover gasket but there are no signs of it if y'all could enlighten me to your past experience and help a brother out before I sell this thing and I don't want to do that because I do love it but I'm sick of dealing with it
08-02-2019, 08:06 AM
#2
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
REAR MAIN SEAL DIAGNOSIS
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, 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: “Crap 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. A little tip here. Rather than use a dizzy gasket, use an o ring instead. NAPA #727-2024. Tips 12 and 13 will help you get your distributor back in place correctly.
08-02-2019, 10:27 AM
#3
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Year: 1995
Model: Cherokee(XJ)
Engine: I6 4.0L
I know this is been beaten to death over and over but I am truly stumped and I'm losing my patience. Have a 97 XJ with this straight 6 and an automatic transmission. I have an oil leak that is driving me nuts it leaks all over my exhaust and my tranny pan. All over my bell housing.
With that being said I'll tell you what I've replaced already I have replaced the oil pan gasket the rear main seal the oil filter adapter Seals and the transmission pan gasket.
It doesn't look like the oil is coming from my oil pressure sensor unit I guess it could possibly be coming from the back of my valve cover gasket but there are no signs of it if y'all could enlighten me to your past experience and help a brother out before I sell this thing and I don't want to do that because I do love it but I'm sick of dealing with it
With that being said I'll tell you what I've replaced already I have replaced the oil pan gasket the rear main seal the oil filter adapter Seals and the transmission pan gasket.
It doesn't look like the oil is coming from my oil pressure sensor unit I guess it could possibly be coming from the back of my valve cover gasket but there are no signs of it if y'all could enlighten me to your past experience and help a brother out before I sell this thing and I don't want to do that because I do love it but I'm sick of dealing with it
You're going to get rid of your Jeep over a (presumably minor) oil leak?
Have you cleaned the entire back of the engine thoroughly with de-greaser and then run the engine (idling, not moving the Jeep) until the oil is HOT?? In other words, starting with a clean slate, and eliminating as many externalities as possible, see if you can identify where the leak is coming from.
08-02-2019, 10:48 AM
#4
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
How about using a 1/4" drive 7/16 socket on an extension and checking the valve cover bolts?
I'll bet there are 2 or 3 loose all the way at the rear.
There's 5 minutes well spent.
I'll bet there are 2 or 3 loose all the way at the rear.
There's 5 minutes well spent.
08-02-2019, 11:55 AM
#5
Newbie
Mine was leaking from the o-ring on the oil filter adapter ($3). Also from the distributor where it goes into the block. There is a gasket or O ring I don't remember. Start by degreasing the engine. Get all that oil out of the way. Then it will help you identify the source easier.
08-02-2019, 12:15 PM
#6
Senior Member
Best thing you can do is degrease the engine and let it run until you see where the oil is coming from. As for rear mains, yes some of them are good and some of them are bad. I wont argue with replacing the rear main regardless while the oil pan is dropped because having to do it twice sucks. That being said... It seems a lot of people botch oil pan/rear mains jobs. Rear mains put in backwards, neglecting the RTV in the corners of the oil pan, bearing caps, timing cover... etc.
08-02-2019, 01:46 PM
#7
Member
I agree with cruiser54, check from the top down. The valve cover gasket is an easy fix and is usually leaky on the 4.0. A known issue is the stock valve covers tend to warp over time, as well, so when I swapped my gasket I also went with an aluminum cover
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08-02-2019, 02:30 PM
#8
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Year: 1990
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Geez, I've gotten by just snugging the bolts down numerous times.
08-02-2019, 02:30 PM
#9
Old fart with a wrench
I used a Victor-Reinz VS50266 neoprene sandwich gasket on both my jeeps and neither one has leaked in over 50K on the WJ or 15K on the XJ. The best part is it is reusable if you don't use sealer.
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08-05-2019, 01:51 PM
#14
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Year: 1990
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