Phantom oil leak question
07-20-2017, 07:46 AM
#1
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Thread Starter
Phantom oil leak question
1995 XJ SE 4x4, auto, 165k miles.
Oil leaks. At least XJ's aren't like 1970's Harley's and Chevy's that were known to leak oil on the showroom floor....
I have an oil leak that has me a little befuddled. I've changed out the valve cover gasket, and also replaced the o-rings on / in the oil filter adaptor. I thought I had things under control, but a trip under the Jeep shows a wet oil pan and transmission pan. I also have wetness under the oil filter adaptor on the block, which is scary after the o-ring change. That was a chore.
It looks exactly like a rear main seal leak and I suspect that's what it is, however, this leak does not drip on the carport. I don't really see how it's not dripping, the pans are both shiny wet, but it's not dripping.
Here's the question; does a rear main leak usually begin leaking while the engine is running & there is oil pressure? That is about the only thing I can think is going on here; oil leaks when the oil is under pressure, but does not leak after the pressure drops. Is that possibly what is going on here?
Oil leaks. At least XJ's aren't like 1970's Harley's and Chevy's that were known to leak oil on the showroom floor....
I have an oil leak that has me a little befuddled. I've changed out the valve cover gasket, and also replaced the o-rings on / in the oil filter adaptor. I thought I had things under control, but a trip under the Jeep shows a wet oil pan and transmission pan. I also have wetness under the oil filter adaptor on the block, which is scary after the o-ring change. That was a chore.
It looks exactly like a rear main seal leak and I suspect that's what it is, however, this leak does not drip on the carport. I don't really see how it's not dripping, the pans are both shiny wet, but it's not dripping.
Here's the question; does a rear main leak usually begin leaking while the engine is running & there is oil pressure? That is about the only thing I can think is going on here; oil leaks when the oil is under pressure, but does not leak after the pressure drops. Is that possibly what is going on here?
07-20-2017, 08:39 AM
#2
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Year: 1999
Model: Cherokee (XJ)
Engine: 4.0 L
That's definitely possible. Also consider that when the oil heats up it becomes thinner and will be more prone to leaking.
A few years ago I actually found my oil pan was rusted and oil would seep through it when it was hot (how the hell does an oil pan rust?).
I suggest cleaning everything very well then paying close attention to what starts to get dirty. Remember that gravity only works one way.
A few years ago I actually found my oil pan was rusted and oil would seep through it when it was hot (how the hell does an oil pan rust?).
I suggest cleaning everything very well then paying close attention to what starts to get dirty. Remember that gravity only works one way.
07-20-2017, 08:41 AM
#3
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
07-20-2017, 12:12 PM
#4
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Well, for the time being, it's apparently very slow. I'll keep an eye on it and hope I don't have to do a rear main for a while....