Connecting rod and main bearing shells

Check the connecting rod and main bearing shells for local corrosion, wear and other damage. Replace the bearing shells if necessary.
Measuring main and connecting rod bearing clearance
To measure main and connecting rod bearing clearance, measure the crankshaft journal diameters and the corresponding inside diameters of the bearings. The clearance is the difference between the bearing inside diameter and the corresponding crankshaft journal diameter.
Crankshaft main bearing clearance: 0.028–0.045 mm
Crankshaft connecting rod bearing clearance: 0.024–0.042 mm

Measuring main and connecting rod bearing clearance using Plastigage plastic gauge

PROCEDURE

1. Clean the crankshaft main and connecting rod journals to remove oil, and blow out the oil passages with compressed air.

2. Install the main bearing inserts into the cylinder block. Install the crankshaft onto the main bearing inserts in the cylinder block. Install the remaining main bearing inserts into the crankshaft main bearing caps. Place pieces of Plastigage plastic gauge on the crankshaft main bearing journals.

3. Install the main bearing caps according to their markings. Tighten the crankshaft main bearing cap bolts in the specified sequence. Do not rotate the engine crankshaft when measuring main bearing clearance. Remove the bolts and main bearing caps. Using the measuring scale, measure the width of the compressed Plastigage strip and determine the clearance.

If the clearance exceeds the maximum allowable value, regrind the crankshaft journals and use undersize repair bearings.
Oil seals

Check the front and rear oil seals for damage or wear of the sealing lips. If any defects are found, replace the oil seal.