Crankshaft Main Bearing

Main Bearing Cap

Image Symbols:

Follow the steps below to tighten each main bearing cap bolt.
Apply engine oil to threads and seating surfaces of bolts, and tighten all bolts temporarily.
Main bearing cap bolts in order of 1 to 10 39.2 Nm (4.0 kg-m, 29 ft. lbs.)
Main bearing cap sub bolts in order of 11 to 20 29.4 Nm (3.0 kg-m, 22 ft. lbs.)





Measure tightening angle using Tool.
Tool number: KV10112100 (BT-8653-A)

CAUTION: Measure tightening angle using Tool. Do not measure visually.

Main bearing cap bolts in order of 1 to 10 40°
Main bearing cap sub bolts in order of 11 to 20 30°
Side bolts in order of 21 to 30 49 Nm (5.0 kg-m, 36 ft. lbs.)
Rotate crankshaft by hand after bolts are tightened. Check if it rotates smoothly.

MAIN BEARING HOUSING INSIDE DIAMETER





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

NOTE: These components must be replaced as a single unit, because they were processed together.

MAIN BEARING OIL CLEARANCE
Method of Measurement





^ Install the main bearings to the cylinder block and main bearing cap. Measure the main bearing inside diameter with the bearing cap bolts tightened to the specified torque.
(Oil clearance) = (Inside diameter of main bearing) - (Crankshaft journal diameter)
Standard:
No. 1 and 5 journals: 0.001 - 0.011 mm (0.00004 - 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 measured value exceeds the repair limit, select main bearings referring to the main bearing inside diameter and crankshaft journal diameter, so that the oil clearance satisfies the standard.

Method of Using Plastigage





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

CAUTION: Do not rotate crankshaft with plastigage installed.

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

NOTE: The procedure when the measured value exceeds the repair limit is the 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 the bearing must protrude.
Standard: There must be crush height
^ If standard is not met, replace main bearings.

MAIN BEARING CAP BOLT DIAMETER





^ Check for bolts (M9 and M12) installed from lower side using the following procedure.

NOTE:
^ Side bolt (M10) is outside the target.
^ Figure shows M12 bolt.

^ Measure bolt diameter "d1" from tip of the bolt to dimension "a".
^ Measure bolt diameter "d2" from the dimension between tip of the bolt and dimension "b" as base station to dimension "c".

NOTE: If a narrower part in the threads is determined by visual check, measure "d2" at that point.

^ Calculate the difference between "d1" and "d2".
M9 bolt
Dimension "a": 9 mm (0.35 inch)
Dimension "b": 15 mm (0.59 inch)
Dimension "c": 20 mm (0.79 inch)
Limit: 0.10 mm (0.0039 inch)
M12 bolt
Dimension "a": 12 mm (0.47 inch)
Dimension "b": 55 mm (2.17 inch)
Dimension "c": 20 mm (0.79 inch)
Limit: 0.15 mm (0.0059 inch)
^ Replace applicable bolts if outside the limit.

MAIN BEARING:

MAIN BEARING

Undersize:

Undersize

Main Bearing Oil Clearance:

Main Bearing Clearance