oil leaking out of motor mount area on 94 yz80!

ok gents. i bought this bike for my little brother as a suprise. so, i got this bike for a very good deal and was told all it needs is a new piston. i get the cylinder bored and a new piston. before i knew it, i had the bike stripped down to the frame and figured i'd re-do the whole bike and make it really pretty for him(hey, hes 12, looks are everything!). well, i go to remove the front motor mount bolt right under the exhaust and oil started leaking out. i about s### a brick when this happened. i wondering if this is normal or do i have a SERIOUS problem on my hands? im going to be ticked if this motor is junk. or maybe thats normal for these??? im not sure as i never had a yz 80 when i was coming up. so i have no experience with these particular bikes. anyone that knows, please tell me im not in for a nightmare!!!

Edited by fmxfourstroke

so no one has any idea? anyone???

A picture would help IMO

to be honest, ive tried looking down in the hole through where the motor mount bolt goes, and i cant see much. i can see the area in the hole thats closer to the piston has a sort of recess, but i really cant see much. ive tried from all angles with a flashlight and cant see anything.

If you have a broken case you need to pull your engine anyway. That way you'll get more light too :)

If you have a broken case you need to pull your engine anyway. That way you'll get more light too :)

yea no crap. but the motors already out of the frame and i still cant see anything. its not cracked on the outside. that would be obvious and i wouldnt have posted on here looking for help.

yea no crap. but the motors already out of the frame and i still cant see anything. its not cracked on the outside. that would be obvious and i wouldnt have posted on here looking for help.

Wow!! Thought you wanted help? Good luck.

Did you completely clean/degrease the bike before you took anything apart?

No engine oil is 'held in' by the cases at the front of the engine where the bolt mounts it to the frame. If in fact, that is where oil came from, it was probably accumulated splooge from the exhaust that was captured in a recess, upon removal of the bolt, you freed.

thank you william1. thats the kind of help i was looking for. yes, the bike was pretty darn clean when i started taking everything apart. there was no cylinder on the motor when i removed it. there was a bit of exhaust gunk on the front of the bottom end right under where the cylinder bolts on, but nothing substantial. i cycled the crank a million times and watched for any defects, which there were none. im hoping nothing detonated inside and poked a hole right behind that motor mount. i think im just going to go ahead and write it off as exhaust splooge and maybe water. i'll just throw the new piston in and run with it.

scottp111, thanks for your help too. :blah:

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