Re: housing bore for main bearings on 7th series 8

Posted by Owen_Dyneto On 2010/8/11 13:11:34

Tom, I'm not 100% sure about this, but I think that bearing shell "crush" only applies to the modern type thin steel-backed shells and not to those very thick babbitted sections. Typically those heavy (1/4" or so?) halves are babbitted without final finishing, installed (they're located by pins, are they not?), caps tightened, and then the babbitt is line-bored to finished dimension. They should not be cut to finished dimensions other than in the installed position with a line-boring jig. Perhaps I'm wrong on this but that's the way several of the major engine shops do that specialize in the early classic-era engines.