Flywheel: Service and Repair

CRANKSHAFT, FLYWHEEL





COMPONENTS

DISASSEMBLY

1. Remove the timing belt train, front case, flywheel cylinder head assembly and oil pan. For details, refer to respective chapters.
2. Remove the rear plate and the rear oil seal.
3. Remove the connecting rod caps.

NOTE: Mark the main O-ring caps to permit reassembly in the original posittion and direction.

4. Remove the main bearing caps and remove the crankshaft. Keep the bearings in order by cap number.

INSPECTION





Crankshaft
1. Check the crankshaft journals and pins for damage, uneven wear and cracks. Also check oil holes for clogging. Correct or replace any defective pert.
2. Inspect out-of-roundness and taper of crankshaft journal and pin.

Standard value
Crankshaft journal O.D 57 mm (2.24 in.)
Crankshaft pin O.D 45 mm (1.77 in.)

Main Bearing and Connecting Rod Bearings
Visually inspect each bearing for peeling, melt, seizure and improper contact. Replace the defective bearings.





Oil Clearance Measurement
To check the oil dearance, measure the outside diameter of the crankshaft journal and the crank pin and the inside diameter of the bearing. The clearance can be obtained by calculating the difference between the measured outside and inside diameter.

Standard value
Oil clearance
Crankshaft main bearing 0.02-0.05 mm (0.0008-0.0020 in.)
Connecting rod bearing 0.02-0.05 mm (0.0008-0.0020 in.)

Limit 0.1 mm (0.004 in.)





Plastigauge Method
Plastigauge may be used to measure the clearance.
1. Remove oil and grease and any other dirt from bearings and journals.
2. Cut plastigauge to the same length as the width of the bearing and place It in parallel with the journal, off oil holes.
3. Install the crankshaft bearings and caps and tighten them to the specified torques. During this operation, do not turn the crankshaft. Remove the caps. Measure the width of the plastigauge at the widest part by using a scale printed on the gauge package. If the dearance exceeds the repair limit, the bearing should be replaced or an undersize bearing should be used.
When installing a new crankshaft, be sure to use standard size bearings.
Should the standard dearance not be obtained even after bearing replacement, the journal and pin should be ground to undersize and a bearing of the same size should be installed.

Oil seal
Check front and rear oil seals for damage or worn lips. Replace any seat that is defective.





Bearing Caps
After Installing the bearing caps, make sure that the crankshaft turns smoothly and the end play is correct. If the end play exceeds the limit, replace crankshaft bearings.

Standard value 0.05-0.18 mm (0.0020-0.0071 in.)

Limit 0.25 mm (0.0098 in.)

Drive Plate
Replace deformed, damaged, or cracked drive plates.

Flywheel
1. Check the clutch disc contacting surface of the flywheel for damage and wear. Replace the flywheel If excessively damaged or worn.
2. Check the clutch disc contacting surface of the flywheel for run-out.

Limit
Flywheel run-out 0.13 mm (0.0051 in.)

3. Check the ring gear for damage, cracks and wear, and replace if necessary.

INSTALLATION





1. Install grooved main bearing (upper bearing) on cylinder block side.
2. Install grooveless main bearing (lower bearing) on main bearing cap side.
3. Both upper and lower bearings for center are grooveless.





4. Install crankshaft. Apply engine oil to journal and pin.
5. Caps should be installed with arrow mark directed toward front of engine. Cap number must be correct.
6. Tighten cap bolts to specified torque in sequence of center No.2, No.4, front and rear caps.

Tightening torque
Main bearing cap bolts 65-70 Nm (650-700 kg.cm, 47-51 lb.ft)

7. Cap bolts should be tightened evenly in 4 to 5 stages before they are tightened to specified torque.
8. Make certain that crankshaft turns freely and has proper end play.
9. Using special tool (09231-21000), install oil seal in oil seal case.





10. Install the oil separator Into the oil seal so that the oil hole in the separator is directed downward (arrow in illustration).
11. Install the new oil seal case gasket and oil seal case assembly.
12. Install the rear plate to the cylinder block.
13. Install the flywheel assembly and tighten the bolts to the specified torque.

Tightening torque
Flywheel bolt 130-140 Nm (1,300-1,400 kg.cm, 94-101 lb.ft)