Seeking out a slight oil drip

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Seeking out a slight oil drip

Postby Zebruken » Wed May 17, 2017 3:15 pm

I'm seeking out the knowledge of the crowd so I can bring more knowledge to the new(er) USA

I have a very slight oil drip that I'd like to find the source of. I know there are a lot of smart people on this forum who may have some insights on where to look.

Here is what I noticed:

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This is the bottom of the bell housing (front of the van on the right, rear on the left). Notice the drip of oil.

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Same drip photographed from the front of the van looking back.

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Passengers side with the inspection panel removed. Note the bit of oil on the edge closest to the transmission.

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Drivers side, same oil on the edge near the transmission.

My theory is that the oil is coming from the rear main seal hitting the flywheel, then running down the inside of the bell housing and escaping through the little hole at the bottom and slightly around the edge of the inspection panel...but I want to hear what you all think. This engine is a recent complete rebuild...but I didn't do it. I just bought it under a month ago and assume that they replaced the rear main when they did the overhaul. But I don't want to assume...

Thanks for any help you can give!


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Seeking out a slight oil drip

Postby north54 » Wed May 17, 2017 3:32 pm

I would assume valve cover gasket:


Or it is the rear main seal.

I'm chasing an oil leak myself of the similar nature and just did the valve cover gasket. Which helped a bit but now have the "drip or two a week" coming from the exact same spot you mentioned.

I think I'm gonna live with it for now before I split my transmission and engine and replace the rear seal :o $$$$$ and time.

Good luck

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Seeking out a slight oil drip

Postby Growlerbearnz » Wed May 17, 2017 5:08 pm

As North54 says, it's usually the rocker cover gasket. If it's a rear main leak the flexplate/flywheel will be oily. A leak from higher up on the engine won't have leaked onto the flywheel.

The rear main seal gets a bit leaky when the engine gets old- it wears a groove into the crank and then it won't seal, even with a new seal. A decent engine rebuilder would have re-faced a grooved crank sealing surface, though. If your engine is making too much internal pressure it'll leak past even a good rear main seal, but I wouldn't expect that from a rebuilt engine.
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Seeking out a slight oil drip

Postby gledhillpete » Thu May 18, 2017 11:18 am

Turbo, feed or return?

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Seeking out a slight oil drip

Postby sealica » Thu May 18, 2017 6:04 pm

Yeah I have this exact same drip. I replaced my valve cover and the leak persisted - suspected Rear Main which I actually went ahead and bought when I was getting other parts for about $40.

Now my valve cover is leaking again so I'll be replacing that again, but kind of regret buying the Rear Main as it's probably better to just create some kind of catch can under that drip since it's really, really minor once the valve cover is fixed ...

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