Rear Main Seal Going?

[Dave Z]

In December 04, I had the rear main seal redone. Yesterday I noticed oil on top of the rear of the motor below the distributor. Next, I found what appears to be oil blowback underneth the car and a very small drip (it doesn't even leak to the ground...yet) between the trans and oil pan. I have put about 700 miles on the car since the work was done, and the oil is almost 1 qt. low already. All gaskets at the valve covers are tight, no leaks. No leak at the oil filter, and no leak at the oil pan itself. Oil pressure reads the right at the first notch after 0 (but it's always read low and always at that mark, at start up and after warmed up). Is the first notch on the gauge 20 or 30? Does this sound like a rear main seal leak?

 

[GerryLP]

If there is a groove on the crankshaft part of the seal, then it could be that the seal part won't last as it should; however, I would be concerned with the low oil pressure and the oil consumption. When the engine oil is cold, the pressure should be higher than normal. Check the clerance of the oil pick up and the oil pan bottom as well as a leak down test to see if your piston rings are going bad. There should be blue smoke between moderate and hard acceleration.


GerryLP:cool

 

[Dave Z]

Thanks Gerry, I've had the car since June 04 and have never had an oil consumption probelm. I believe the reason it's low is due to the leak. As for the pressure, you're right, I am concerned but the car has and still does run great. I've chalked it up to the gauge (sending unit is new) being old and going (gone) bad mainly due to the fact the pressure is always at the same mark, cold or hot.

 

[Jack]

Ditto the groove on crank journal. Also, the intake manifold can leak oil at rear just below distributor ... then it runs down & can mimic RMS leak. Clean off the back of block & rear intake ... monitor that area before you pounce on your mechanic. Also, timing cover-harmonic balancer seal can leak & blowback. Some have op sending unit adjacent to dist ... check new sending unit for leaks too.
JACK:gap

 

[Bob Chadwick]

We have another thread going on the same issue.

 

[Bill75]

Oil below the distributer on top of the motor?? How could that be the rear main? Maybe a pressurized crankcase due to a bad PCV valve blowing oil vapors up around the dist shaft, might be worth a check.

 

[Bolisk]

Oil on the back of the engine below the distributor could be a leak from the Oil pressure gague line fitting. I have this exact problem. After I turn the engine off, the oil backflows thought the pressures line (the one to the gague), and leaks all over the back of the engine about where the distributor is.

 

[Evolution1980]

Psst...Bolisk... prior to your post, the last entry in this thread was back on 02-22-05, 12:34 PM. The person that originally created the thread isn't even a member here anymore.

How did you come across this old thread? :L

 

[Bob Chadwick]

How did you come across this old thread? :L

We tell them to do a....Search!!!:W

 

[Evolution1980]

We tell them to do a....Search!!!:W

That was the only thing I could think of. :L