Connecting Rod: Service and Repair
STANDARD PROCEDURES - CONNECTING RODS AND BEARINGSCONNECTING ROD BEARINGS
The bearing caps are not interchangeable and should be marked at removal to insure correct assembly.
The bearing shells must be installed with the tangs inserted into the machined grooves in the rods and caps. Install cap with the tangs on the same side as the rod.
Fit all rods on one bank until complete.
Limits of taper or out-of-round on any crankshaft journals should be held to 0.015 mm (0.0006 inch). Bearings are available in standard, 0.025 mm (0.001 inch), and 0.254 mm (0.010 inch) undersizes. Install the bearings in pairs. Do not use a new bearing half with an old bearing half. Do not file the rods or bearing caps.
1. For measuring main bearing clearance and connecting rod bearing clearance use plastigage (Fig. 57). Refer to Engine Specifications for bearing clearance specifications.
NOTE: The rod bearing bolts should be examined before reuse. If the threads are necked down the bolts must be replaced (Fig. 58).
CONNECTING ROD BOLTS
1. Examine connecting rod bolts for stretching. Stretching can be checked by holding a scale or straight edge against the threads. If all the threads do not contact the scale the bolt must be replaced.
2. Before installing the nuts the threads should be oiled with engine oil.
3. Install nuts on each bolt finger tight. Then alternately torque each nut to assemble the cap properly.
4. Tighten the connecting rod cap nuts to specifications.
CONNECTING ROD SIDE CLEARANCE
1. Mount a dial indicator to a stationary point on engine. Locate probe perpendicular to and resting against the connecting rod cap being checked. Move connecting rod all the way to rear of its travel. Zero the dial indicator. Move connecting rod forward to limit of travel and read the dial indicator (Fig. 59). Compare measurement to specification listed in engine specifications. Repeat procedure for each connecting rod. Turn crankshaft for connecting rod accessibility.