Rear main seal leaking

Kevin 007

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Ive developed a bad engine oil leak from the bellhousing area on my 99 7.3. No major leaks up in the valley or under the turbo, the rail plugs area on the back of the heads are dry. Just some "sweating" around the HPOP and that's about it....unless I'm missing something?. I switched to synthetic 5w-40 Mobil Delvac aprox 14000 miles ago and would like to keep running it for injector longevity and better cold starts. It just started leaking less then 500 miles ago now. Is there anything else to look for other then the rear main seal? Its leaking a drip every 5 seconds or so.

I might switch back to 15w-40 to see if that helps. Not looking forward to doing a rear main seal in winter out in the snow.
 

79jasper

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Imo, a rear main shouldn't leak that fast. Try parking downhill.
You may be able to see something by removing the dust cover.
If it's actually coming from inside the bell housing, I would still look up top more.
Can you see the drain hole in the valley? Is it actually dry?

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Garbage_Mechan

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Rear mains on 7.3 PSD seldom leak. My test procedure on this is to pressurize the crank case to 2 or 3 psi and use soapy water to find it. My last pesky one was poor silicone seal at the top of the rear main seal plate (not the seal) but it only leaked after a long hard run.
 

Kevin 007

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I cant see the drain hole, there is some minor oil in the valley and has been for some time, seems to accumulate for HPOP area over time. I will have a better look. Might remove the intercooler piping to actually see better in there to possibly see something dripping.
 

Kevin 007

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There was nothing coming from the valley, pretty much all dry in there, including under the turbo. really seemed to come from inside the bellhousing. Never did find out where it was coming from. THEN.....almost overnight, it stopped leaking. driven about 300 miles so far on no leaks. The occasional drip but no more steady drip every few seconds.
Not sure what to tell ya all.
 

Thewespaul

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There was nothing coming from the valley, pretty much all dry in there, including under the turbo. really seemed to come from inside the bellhousing. Never did find out where it was coming from. THEN.....almost overnight, it stopped leaking. driven about 300 miles so far on no leaks. The occasional drip but no more steady drip every few seconds.
Not sure what to tell ya all.
Did you check to see if it still had oil to leak? LOL
Glad it fixed itself, rear mains aren’t fun to change out
 
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