• 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.

rear main seal?

F

f1tbiker6

NAXJA Forum User
Location
Bridgeport PA
so at highway speeds when i let off the gas and just coast i am getting a bit of smoke. but when im on the accelerator the smoke goes away. i pulled over and checked it out and i have a slight drip where the rear main seal would be, dripping on to the downpipe. but under normal city driving i have no smoke issues. is it my rear mail seal?

would i be okay not fixing it for a 120 mile trip to rousch creak, and just bringing extra oil with me and dealing with the slight smoke on the highway?
 
How much does it leak? My rear main seal used to leak on a different motor...it never leaked a lot, maybe half a quart every 3 weeks or so. It used to smoke though when it would hit the exhaust. It was bad enough that people would point at my jeep in traffic and tell me they thought it was on fire. I drove it like that for several months with no problems, other than topping off the oil every once in a while.
 
js_customs said:
How much does it leak? My rear main seal used to leak on a different motor...it never leaked a lot, maybe half a quart every 3 weeks or so. It used to smoke though when it would hit the exhaust. It was bad enough that people would point at my jeep in traffic and tell me they thought it was on fire. I drove it like that for several months with no problems, other than topping off the oil every once in a while.
Click to expand...

i doesnt leak much at all. under normal driving i dont notice any smoke at all or drips in my driveway. its just on the highway i notice a bit of smoke behind me when i let off the gas.
 
mine leaks to its got 200,000 miles on her ! but does not smoke like that ! i would say you have bigger problems ?? rings ,seals ,valves, tired old engine , etc.........
 
My XJ has had a leaky rear main for 4 or 5 years now, there is probably no seal left, and I have no smoke issures. Probably not your problem.
Id guess w/ john, or even a over heating tranny. I know when my tranny has over heated it boils up out the bottom of the dipstick and flows onto the exhaust and smokes like crazy, but that doesnt explain why its on deceleration...
 
jeeperjohn is right on. Smoke on deceleration is indicative of bad valve guides and/or seals. The rear main has nothing to do with it, and before you label it rear main, make sure it isn't a leaky valve cover. They tend to leak at the back and run down and present just like a rear main.
 
i had a leak comming out the rear of my engine at the bell houseing and when i pulled out the engine it eneded up being the tranny that was leaking.make sure its not tranny or clutch fluid if you have a clutch. If your getting a cloud of smoke out of ur engine maybe you got a bad bearing thats heating up and making it smoke? ive seen a guy with a leaking rear tranny seal catch fire, the drip was landing on the exaust, burnt his truck to the ground.
 
You would need to have one hell of a leak if the oil dripping on your exhaust is causing noticeable smoke. I personally have never seen/heard of a leaky valve cover or rear main that would create such an occurrence.

Furthermore, you stated the smoke only appeared during periods of coasting or deceleration. You have received an answer as to why this happens.

We can only help those who are willing to be helped. Listen to the information provided, or search elsewhere. Arguing won't help, especially if your name is 'jasonsxj' - you are not helping.

Best of luck.
 
You must log in or register to reply here.

Similar threads

S
Scratched bearing while replacing rear main seal
Replies
3
Views
1K
waxer
waxer
M
Oil pressure question
2
Replies
26
Views
3K
Money_Pit_Incoming
M
E
Ok so ive been putting this off for 20 years
Replies
7
Views
1K
denverd1
denverd1
paulhead
Temperamental rear main seal leak?
Replies
7
Views
821
RCP Phx
R
M
New to my XJ & wrenching - How to choose parts and what to prioritize?!
2
Replies
28
Views
4K
flyin_ryan
F
Back
Top