Crankshaft: Service and Repair

REMOVAL
1. Remove the rear crankshaft oil seal.
2. Remove the engine oil pan. Refer to Oil Pan Removal.
3. Mark the connecting rod caps in order to correctly reassemble the connecting rods.
4. Turn the crankshaft to bottom dead center.





5. Remove the connecting rod nuts and caps.





6. Remove the connecting rod bearings.
7. Install a 3/8 inch piece of fuel or vacuum hose over the connecting rod bolts in order to avoid damage to the crankshaft journals.
8. Remove the main bearing caps and remove the main bearings. Mark the main bearing caps in order to insure that they are installed in the same place from which they were removed.





9. Remove the crankshaft.
10. Clean the crankshaft.
^ Clean any obstructions from the oil passages on the crankshaft.
11. Inspect the keyway and the threads in the front of the crankshaft and the threads in the flywheel bolt holes.
12. Inspect the bearing journals and inspect the thrust surfaces for the following items:
- Wear
- Cracks
- Chips (Replace the crankshaft if the crankshaft is chipped)
- Gouges (Replace the crankshaft if the crankshaft is gouged)
- Roughness
- Grooves
- Discoloration due to overheating (Replace the crankshaft if the crankshaft is discolored)
13. Use a micrometer in order to measure the crankshaft taper. If the crankshaft taper is not within specifications, replace it.
^ Main journal taper is 0.005 mm (0.00019 inch).
^ Rod bearing taper is 0.005 mm (0.00019 inch).
14. Measure the crankshaft runout. If the crankshaft runout is not within specifications, replace it.
^ 0.005 mm (0.00019 inch).

INSTALLATION
1. Apply engine oil to the main bearing inserts.
2. Install the upper main bearing inserts.
3. Install the crankshaft.





4. Install the lower main bearing inserts to the main bearing caps.
^ Make sure that the inserts are the correct size.
^ Apply engine oil to the inserts.
5. Measure the main bearing clearance. Should be between 0.015-0.047 mm (0.0006-0.0019 inch)





6. Install the main bearing caps to the engine block.
7. Install the main bearing cap bolts to the engine block.
^ Tighten the main bearing cap bolts first to 50 Nm (37 ft. lbs.).





8. Measure the crankshaft-end play using the following procedure:
a. Firmly thrust the crankshaft rearward.
b. Firmly thrust the crankshaft forward.
c. This will align the main bearing and the crankshaft thrust surfaces.
9. Tighten the main bearing cap bolts to 95 Nm (70 ft. lbs.).





10. Measure the crankshaft end play at the front end of the rear main bearing with a feeler gauge.
^ The crankshaft should still be wedged forward.
^ The proper clearance is 0.0511-0.1780 mm (0.002-0.007 inch).
11. Install the oil pump.
12. Install the oil pan.