Shells main crank

[Saward1]

Hi my first post please help
I need new main shaft bearings
The shells have numbers 1203486
Also. A2783

Can anyone tell me the size I need it’s a 948 1961
Regards Ian

[philthehill]

If the bearings are for a re-ground crankshaft then the under size will be stamped on the underside of the shell i.e. - 0.020".
If the bearings are for a non reground crankshaft then there will be no i.e. - 0.020" stamped on the shell and they will be standard shells.