picked up a really cheap m50

[mazie30]

so i was in the market to buy a engine, searched around for a while and was thinking, s50, 2jz, random engines, then stumbled upon a m50 in the area, talked the guy down to $150 and went and picked it up that night
comes with harness, and ecu. The only con is that he over revved it... once

shifted from 3rd to 2nd gear instead of 4th, but only once. then said the engine was running rough.
got it up on the stand the other night finally and am starting to take it apart. i am pretty excited because this is my first engine and i am excited to learn.
it is a m50b25 from a 1992 525i
what exactly could go wrong with an overrevved engine?

thanks in advance.
mazi

[R1dd1ck913]

It could have spun a bearing.

[golde30]

most likely the exhaust side valves are bent. head will most likely need to be send out to be checked and rebuilt. may or may not be worth it.

[surebimmer]

Only takes once to money shift. My bet is bent valves for sure. Going to have to do a leak down test or pull the head. golde30 knows too well about this. :p