Re: "Acceptable" bearing clearance

Posted by Owen_Dyneto On 2015/4/27 8:25:37

Even the service bearings in 0.002 undersize would still leave quite a bit more clearance than one would want, though it may be the best "quickie" fix I wouldn't count on it for a long service life and surely won't do the crankshaft any good. Best solution as Ross notes is to have the crankshaft turned to a standard undersize. But another thought if the journals are evenly worn (without flatspots or uneven wear) is to find a set of main bearings in "semi", meaning unfinished to final size, and have them sized to fit your current crankpin dimensions. I did crankpins on a 356 Packard years ago and all I could find at that time were "semi" mains which I had finished to the dimensions I wanted. I don't believe "semi-finished" bearing shells were a listed Packard service part, I got mine from a Federal Mogul facility.

PS - if the main bearing journals show that much wear I'd expect the rod journals to show much more.