Am I being to pickey?

R

rsicard

Member
Assembling a SBC crankshaft, main bearings and block. Assembled number 1 and 5 bearing saddles with bearing inserts. 2,3 and 4 saddles had NO bearing inserts. Installed crankshaft into the block with 1 and 5 bearing saddles and new bearing inserts. Put a dial indicator on 2,3 and 4 crankshaft journals and checked run-out. Those three came out ZERO run-out. Assembled and torqued all bearing saddles with inserts. Attached an inch pound torque wrench to the snout of the crank, turned and measured friction. At the low end it was 15 inch pounds and at 180 degrees opposite it peaked out at 35 inch pounds. That is double+ the low end reading. Am I just being TOO pickey?

It seems there may be a slight egg shaped number 1 or 5 crank journal or possibly a bend in the crankshaft? Your thoughts please! Thanks ahead of time.
 
15 inch pounds = only 1.25 ft lbs at that level of rotational drag, any inconsistency in the assembly lube thickness, or journal surface finish could and probably will cause a difference in rotational resistance or drag, if it spins fairly easily with a couple fingers on the crank snout with all the mains torqued down and your plastic-gauge checks and micrometers say the bearing clearances are correct your going to be fine, I generally look to have less than 5 ft lbs resistance , on rotating a crank and less than 10 lbs to get it to start rotating as the surface tension of most assembly lubes will resist rotation untill it starts to rotate, then the resistance to rotation drops off rapidly


THERES A THREAD ON THIS SUBJECT
viewtopic.php?f=53&t=852&p=1311#p1311
 
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