i spun a main, due to a bad oil leak (o-ring behind oil cooler). opened it up, with the motor in the car. when i took down the main bearing bridge, the spun bearing was obvious, i was burned and broken. also had a lot of metal flakes in the oil.

i DO NOT want to take the motor out of the car, so this is my question. can i replace the main with the crank still in? i was able to get the top half of the bearing out with a thin feeler gauge. the crank has a very small "scratch" on it, maybe 1/64" long and even less in depth. its microscopic but i was under there for about an hour looking for ANY deep gouges/scoring. thats the only thing i found. all the other bearing, mains and rod, are good.

so is it ok to slide another bearing in there the way i got the top one out, put one on bottom and slap it together?

 

Are you sure the block wasn't damaged in the process? Take the crank to a machine shop and make sure it's still within spec. If the block and crank are fine, replace the bearing and chug along.

 

taking the crank out means taking out the motor, at least it does to me. thats what i didnt want to do. i can plastigage it with everything still in motor and car. i dont want a long repair process, its my daily.

i found no other damage, other than the micro scratch on crank journal that i mentioned above.

assuming there is NO block or crank damage, can i just put a new bearing in there and be ok?

 

obviously you need to inspect the motor, flush the oil system find out how much metal was lost off of the bearing. You should just get the crank inspected like everyone will say. but since you dont want to pull the motor then just flush the oil system change out the bearings (yes all of them) and try it. If it doesnt work then you will find out that you did the wrong thing.