Service Limits & General Specifications

INNER DIAMETER OF MAIN BEARING HOUSING





^ Install the main bearing caps with the main bearings removed, and tighten the mounting bolts to the specified torque.
^ Using a bore gauge, measure the inner diameter of the main bearing housing.
Standard: 68.944 - 68.968 mm (2.7143 - 2.7153 inch)
^ If out of the standard, replace the cylinder block and main bearing caps as an assembly

NOTE: These components cannot be replaced as a single unit, because they were processed together.

OIL CLEARANCE OF MAIN BEARING
Method of Measurement
^ Install the main bearings to the cylinder block and bearing cap. Measure the main bearing inner diameter with the bearing cap bolt tightened to the specified torque.
(Oil clearance) = (Inner diameter of main bearing) - (Outer diameter of crankshaft journal)
Standard:
No. 1 and 5 journals: 0.001 - 0.011 mm (0.0004 - 0.0004 inch)
No. 2, 3, and 4 journals: 0.007 - 0.017 mm (0.0003 - 0.0007 inch)
Limit:
No.1 and 5 journals: 0.021 mm (0.0008 inch)
No. 2, 3, and 4 journals: 0.027 mm (0.0011 inch)

^ If the measured value exceeds the repair limit, select main bearings referring to the main bearing inner diameter and crankshaft journal outer diameter, so that the oil clearance satisfies the standard. Refer to "HOW TO SELECT MAIN BEARING".

Method of Using Plastigage





^ Remove oil and dust on the crankshaft journal and the surfaces of each bearing completely
^ Cut a plastigage slightly shorter than the bearing width, and place it in crankshaft axial direction, avoiding oil holes
^ Tighten the main bearing bolts to the specified torque.

CAUTION: Never rotate the crankshaft.

^ Remove the bearing cap and bearings, and using the scale on the plastigage bag, measure the plastigage width.

NOTE: The procedure when the measured value exceeds the repair limit is same as that described in "Method of Measurement".

CRUSH HEIGHT OF MAIN BEARING





^ When the bearing cap is removed after being tightened to the specified torque with main bearings installed, the tip end of bearing must protrude.
Standard: There must be crush height
^ If the standard is not met, replace main bearings.

Part 1:

Part 2:

MAIN BEARING





Undersize





Main Bearing Clearance