Please help - Oil leaking into bell housing

I have a 99 3.8 in an off road car. I just rebuilt it. The first trip out it is leaking oil from the bell housing. I pulled the motor, flywheel and adapter plate. I was expecting to see oil behind the flywheel. But not really. The clutch pressure plate and bell housing are covered in tons of oil. Almost like the oil is coming out of the end of the crank. Can anyone help?
 
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So, is only the [bottom] of the bell housing soaked in oil?

If so, then your rear main seal requires replacement.


If the entire bell housing is soaked in oil then your leak may be coming from the intake.
 
Oil is all over in the bell housing. The clutch pressure plate is covered on the outside.
Where in the intake would the oil be coming from? The intake manifold? Then it would be all over the outside of the motor too right?
 
Rear main, or oil passing through the flywheel bolts if you didn't use a sealant on the threads.

Would also be leaking from rear of intake, but if the bellhousing is flush and tight, it seldom leaks inside from there.

Sometimes the rear main seals need a sleeve on the crank if there is a faint wear mark.
 
You had better look closely at the oil pan gasket too
The rear of it can also leak into the bellhousing area
If you were to take it in for repair at a dealer for instance
They would not guarantee the leak unless you replace both the pan gasket and the rear main oil seal
 
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Thanks, I had the motor out of the car. I paid attention to the intake, heads, oil pan. I replaced the rear main. I put it all back together and got the motor in the car yesterday. I'll start it today. Going to have an opportunity to get it out and run it next weekend.
 
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Thanks, I had the motor out of the car. I paid attention to the intake, heads, oil pan. I replaced the rear main. I put it all back together and got the motor in the car yesterday. I'll start it today. Going to have an opportunity to get it out and run it next weekend.
It likely didn't go on [flat] over the crank. The sleeve that was mentioned above is a really good idea for engines with some miles.
 
I hope I don't have to deal with that as I JUST rebuilt it. Positive side. The engine seemed to be original as the bearings inside were dated 1999. Hoping the crank is in good shape. Themot motor had no leaks before I rebuilt it.
 
Well. The motor leaked again. I used a new oem seal, black permatex on it when I put it in. I guess I'll order a new seal and one of the crankshaft repair sleeves. Anyone recommend one brand over the other? What do you use to seal it?
 
I use no sealer on the rear main
You only need a sleeve on the crank if it is undersize or grooved
As far as manufacturers, you take what you can get
Felpro, Victor, Perfect circle, they all make the sleeve or offer the sleeve
 
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Well I'm at witts end. I pulled the motor, again. I put the sleeve on the crank. New rear main. Fing thing is still leaking. I'm thinking about just replacing the crank. The original one had years of service. I would absolutely love to find a shop that know these motors. Not the on lines ones. Anybody know of one in southern California? Before I go to supersix or something I could spend the same money on a crate Honda for crying out loud.
 
Thanks. Hoping I'm not crazy. I mean, the machine shop who did my heads and all of the machine work "should have" caught a bent crank. Right?
But in "theory, I should be able to just replace the crank, crank bearings, rod bearings and gaskets. Put it back together right? I guess looking for a reputable source for a new crank.
 
Random thought last night. So... I'm a competent vw wrench. This was my for time tearing into a 3.8. The comment about possibly having a bent crank made me think.
So my question is. Can I install my flywheel wrong? On a vw, they only go on 1 way, so if all of the bolt holes line up it good. Could that do it? Make my rear main keep leaking?
Because I'm ready to tear the thing down again and just rebuild it from scratch. Just don't want to throw away the money.