Cleaning

Cleaning

CAUTION: Do not use a caustic cleaning solution or damage to connecting rods may occur.

Remove the connecting rod bearings from the connecting rod and cap. Identify the connecting rod bearings if they are to be reused. Clean the connecting rod in solvent, including the rod bore and the back of the connecting rod bearings. Blow out all passages with compressed air.

Inspection

CAUTION: Do not ream or hone the pin bore in the connecting rod. Replace damaged connecting rod nuts and bolts or engine damage may occur.

Inspect the connecting rods for signs of fractures and the bearing bores for out-of-round and taper. If the connecting rod bore exceeds the recommended limits and/or if the connecting rod is fractured, replace the connecting rod. Check the inner diameter of the connecting rod piston pin bore. If the pin bore in the connecting rod is larger than specification, install a 0.03 mm (0.0012-inch) oversize piston pin. On 3.0L (2V) engines, prefit the oversize piston pin to the piston pin bore by reaming or honing the piston to provide 0.005-0.012 mm (0.0002-0.00048 inch) clearance (light slip fit). Assemble the piston, piston pin and connecting rod following the procedures for the specific engine being serviced.
The connecting rods and related parts should be carefully inspected and checked so they conform to specifications. Various forms of engine wear caused by these parts can be readily identified.
A shiny surface on either pin boss side of the piston or a sideways wear pattern on the entire piston skirt usually indicates that a connecting rod is bent.
Abnormal connecting rod bearing wear can be caused by a bent connecting rod, worn or damaged crankpin or a tapered connecting rod bore.
Twisted connecting rods will not create an identifiable wear pattern, but badly twisted connecting rods will disturb the action of the entire piston, rings and connecting rod assembly. Twisted rods may also cause excessive oil consumption.