Replace bearings after crush or put them back where they came from?
I have a 454 bbc that was put together buy a friend of mine but never cranked. To be safe I disassempled the short block to clean it since it had been sitting for a period of time uncovered. When I pulled the crank out I noticed scratches in all the bearings, a few deep enough to catch your fingernail on. The crank sat out after being disassembled and got some light surface rust on it so I took it and had the oil holes chamfered and the journals polished. The crank is well within spec for bearing tolerances, however I am unsure about using the unused bearings since the have been installed and tourqued down previously and have some light scratches, plus the crank has been polished. I realize that main bearings aren't that expensive but I don't want to throw them away if they're safe to use.
I'd spend the $50 and replace them, that way you won't be kept up at
night worrying whether or not they'll cause you any trouble.
Reusing the bearings after them being torqued isn't a problem,
but why are the bearings scratched? was the engine cleaned?
was the assembly area clean? was he just careless?
I think I would have everything cleaned, & then use new bearings, just to be safe.
I'm really not sure why they are scratched, but it is obviously from some foreign material that wasn't supposed to be there. All of the scratches resulted from the engine being turned over by hand after assembly. I pulled it apart because I was pretty certain that some sort of contamanent had entered in to the short block, and rather than risk it I figured it was definately worth the time to pull it apart and thoroughly clean it.
Here is my rule. If the bearings were installed and NOT heat cycled (engine started) i will re-use them. If the engine was started, even one dyno pull and i need to take it apart they get replaced.
In your case becasue of the dirt they need replaced. You also need to get a bottle brush and clean the oil holes in that crank. I have seen it many times where the grinder will take the crank out of the grinder, blow it off and bag it. Figuring the builder will clean it, the builder figures that the crank grinder cleaned it..
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