The crank should be ground to the exact dimension given and the
rod bearing shells are supposed to be supplied to give the proper
clearance. I have always supplied the grinder with the rods and
the new shells so they can verify the crank is ground to the
proper clearance. A good shop should have asked for them on a
unique job like this.
You can easily check the clearance yourself by using a product
called "plastigage." This is a plastic spagetti placed between
the bearing shells and the crank, and the rod caps tightened. The
caps are carefully removed and the squished material compared to
a chart which will show the clearance. Main bearings should also
be checked.
By having the rods fixed, I assume you mean the big ends were out
of round and they were reconditioned. That is the caps and rods
mating suffaces ground slightly, the cap attached to the rod and
the whole assembly line bored. This should be a standard
proceedure, or check on all rods during a rebuild. All rods
should also have been checked for twist, and parallel big and
little ends.
Also make sure there is absolutely no lubricant, grease, dirt,
etc, between the shell and the rod itself, and the tangs and ends
are correctly located.
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