Crankshaft Main Bearing Journal Clearance

Check

NOTE: Refer to the appropriate Engine article for the specification.

NOTE: Crankshaft main bearing journals must be within specifications before checking journal clearance.

Remove the crankshaft main bearing cap and crankshaft main bearing.
Position a piece of Plastigage across the crankshaft main bearing surface.

Courtesy of FORD MOTOR COMPANY
NOTE: Do not turn the crankshaft while carrying out this procedure.

Install and tighten to specifications, then remove the crankshaft main bearing cap.
Measure the Plastigage to get the crankshaft main bearing clearance. The Plastigage should be smooth and flat. A changing width indicates a tapered or damaged crankshaft or crankshaft bearing.

Courtesy of FORD MOTOR COMPANY