Connecting Rod Bearing: Testing and Inspection

NOTE:
^ Before the bearing clearance is measured in conjunction with the fitting of new bearings, the crankpin out-of-round (ovality) and taper must be checked.
^ Bearing clearance should be measured with Plastigage, part No. (45) 30 06 558, or equivalent, available in three thicknesses. Use type PG-1 (green).

CAUTION When measuring bearing clearance by means of Plastigage, to prevent bearing failure due to oil starvation, make sure that none of it gets into the oil holes.

1. Clean the parts to be measured, making sure that they are dry and free from oil and dirt.
- Place a strip of Plastigage in the lengthwise direction of the shaft.
2. Install the bearing cap and tighten nuts to: 55 Nm (41 ft. lbs.).

NOTE: The crankshaft must remain absolutely still during measurement.

3. Remove the bearing cap.
- The strip of Plastigage should now be stuck either into the bearing cap or on the crankpin.
4. Measure the width of the Plastigage strip using the scale printed on the package and read off the clearance.
- One side of the packaging is calibrated in mm and the other in thousandths of an inch.
- Measure the strip at its widest point, taking care not to touch it with your fingers.
- Connecting rod bearing clearance specification: 0.026-0.061 mm (0.0010-0.0024 inch).