crank machining

[turboadict]

How far under can you grind a stock crank?

I have one that let go of a rod and put some scores into the journal. Not too deep but not sure if the journal will go down enough to take them out.

Has anyone ever had a crank repaired in the way of welding deep scratches and re-grinding?

The rest of the crank is original spec and in good shape except for the one rod journal.
would seem a shame to scrap it if it can still be made servicable.

 

[bison]

Its not worth repairing. You can buy a good .010 under crank for around $250. If you were going to use it want it checked for cracks and straightness first. Ive never seen many cracks successfully welded on cranks. I know of one that failed in a stage 1 a few years back. It cracked right next to where it was welded. The only welding id do woul dbe the thrust if it needed it.

 

[thadeal4real]

just mag it if no cracks then just grind it and run it the nicks/dents will just be extra pockets of oil

 

[turboadict]

There are no visible cracks (wouldn't know for sure without testing tho), just scratches in the journal bearing surface.

I wouldn't normally consider it but for the fact that cranks here in the UK are a bit thin on the ground, there's probably less than ten turbo Buicks over here.

Would be nice to have a spare , but......... if I wasn't sure its do-able it probably wouldn't be worth the risk of potential mechanical disaster.

 

[turboadict]

How far under will these cranks go, 0.030, 0.040 ?

 

[thadeal4real]

30 under is safe