different measurement, then the crank was turned to the wrong size or
the bearing is incorrect. (Note: undersize bearings should have a
measurement on the back that matches a measurement on the crankshaft
journals left by the machine shop.)
The Plastigage is placed on top of the crank and the bearing caps
are test fitted in place, which crushes the Plastigage. After the
bearing caps are removed, the Plastigage’s width is compared to a
scale on the packaging, which offers a clearance width. If the width
checks out to factory specifications, the bearing caps can be
reinstalled.Each of this engine’s bearing clearances measured to within the
factory specifications of .002 inches, so the main bearings were
reinstalled and torqued. Then, the crankshaft’s end play was checked. A
dial indicator was installed on the end of the crankshaft to detect
forward and rearward play. A pry bar was used to push the crankshaft
back and forth. The shop manual for this car gives an allowable range
for play, but generally, .003 to .008 inches is the norm. The play of this