The engine must be removed from the machine to perform this test.
Remove the flywheel from the crankshaft. (See Remove and Install Flywheel in this Group.)
 – Remove bolts from the flywheel housing. Remove the flywheel housing from the engine.
 – Before removing the main bearing, measure the crankshaft end play.
 – Install a dial indicator on the engine block. Move the crankshaft in and out to measure end play. Record the measurement.
 – Remove the 16 cap screws (A) and ladder frame (B). Do not remove the bearing inserts at this time.
 – Wipe oil from bearing insert and crankshaft journal.
 – Put a piece of Plastigage TM (C), or an equivalent, on each of the four crankshaft main bearing journals as shown.
 – Reinstall the ladder frame. Tighten cap screws to specification in the sequence shown.
 – Remove the ladder frame.
The flattened Plastigage® may be found on either the bearing insert or crankshaft journal.
Use the graduation marks on the envelope (B) to compare the width of the flattened Plastigage® (C) at its widest point.
 – Determine bearing clearance on each main bearing. The number within the graduation marks indicates the bearing clearance in inches or millimeters depending on which side of the envelope is used.
 – Remove Plastigage®.