Can a rear main seal fix itself?

[headdamage]

I know this is not possible but oddly I had oil poring out of the flywheel housing drain hole a few weeks ago when I started and moved the 200tdi 90 after being parked all winter. I just had a better look under the truck today and ran the engine for about 15min and there is no more oil coming out. Yes I did check the dipstick and there is oil in the engine.

I'm trying to figure out if it might not be the rear main seal before taking the engine out just incase I'm getting ready to waste a load of time and effort.

[binch]

How about the input seal of the gearbox? ???

[Red90]

How about the input seal of the gearbox? ???

It was engine oil.

[Matt H]

Can a seal fix itself?  Well yes, absolutely. 

It will leak/weep again and never seal as well as new OEM seal but they do soften back up and do a decent enough job of keeping thicker oils in place..

I'd leave it and just keep an eye on things

My 2c

[Red90]

One thing I would suggest before making a final decision is to go for a long drive with the goal of getting the oil hot.  It takes about half an hour on the highway to get the oil up to full temperature.  It would be good to know that it is still sealing once the oil is as thin as possible.

[ugly_90]

It sounds like it would be a bad time to change to synthetic engine oil then.
Hopefully that wasn't a factor in your last few changes, even new semisynthetic would have been a bad choice if it played a role in that leak.

The flywheel housing has that hole for this purpose, so if it seals at running temperature, or has a very small leak, then it may not be worth the effort to disassemble further. I assume you have something like an R380 manual gearbox, and that your clutch system has been recently renewed? Perhaps the rear main seal could go with that job, as I've done both too many times on the 2.5D.

It sounds like you're confident the leak is really through that flywheel hole. In the past, it had been difficult for me to find the source of an oil leak coming from the top rear oil line from the head of the 2.5D. it's located next to the bulkhead, and is really hard to inspect there. I don't think the 200tdi has a similar oil line there.

[headdamage]

So today I took the 90 out for a drive, did about 50km including hwy up to 100kph. Drove it in and out of the garage like when I first noticed the leak and... no leak now, wtf?

[binch]

Hands on healing by Andrew!!!! ;)