Measurement method
Install the main bearings in the cylinder block and covers. Measure the inner diameters of the main bearings by tightening the bearing cap bolts to the correct torque.
(Oil clearance) = (Main bearing inner diameter) - (Outer diameter of the crankshaft journal)
- Standard clearance: 0.039-0.066mm
If the measured values are greater than the specified values, select the main bearings according to the inner diameter of the main bearing housings and the outer diameter of the crankshaft main journals so that the oil clearance is correct (see further section «The procedure for selecting main bearings»).
Measuring method with calibrated plastic wire
Wipe off dirt and oil from the crankshaft journals and bearing surfaces.
Cut the wire into pieces slightly shorter than the width of the bearings, lay them in the direction of the axis of the crankshaft, but not on the oil holes.
Tighten the main bearing bolts to the correct torque.
Attention: Do not rotate the crankshaft.
Remove covers and bearings and measure the width of the pieces of wire with a scale on its packaging.
Note: If the measured value exceeds the norm, take the same measures as indicated in par. «Measurement method».