quote:Originally posted by JFB #05177:
I have assembled bearings that required 0.035" vertical clearance and even greater, but the journel diameters were 24" (and greater). they do make plastic gauge that size, but NAPA thinks you are crazy and don't carry it. for 0.035" clearance checks, I would prefer 6 amp fuse wire or three twist of 1 amp
funny story about plastic guage. checking small drive bearings that should have been 0.003". I noticed the new guy with the wrapper referance was going "its not 0.002, and its not 0.004" over and over. So I asked him why he didn't call it 0.003". he replied the plastic gauge was still red and to be 0.003" it needs to turn white.
Yes, Kerry is correct, the decimal point is off by 10 in my post. .0035" is a lot of clearance on a main bearing but used for a time in competition engines.
I'd have to look at my assembly notes but the last two engines I did were .0015" (347) and .0020 (351c).
That is the thickness of the film of oil that the crankshaft is running on. Viscosity would be determined from those clearances for a specific film strength (not MM film strength Mark
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