installed in their original locations. Turn the crankshaft until the connecting rod from which the cap is being removed is down and remove the bearing cap. Push the connecting rod and piston assembly up into the cylinder. Repeat this procedure until all the connecting rod bearing caps are re-moved.
8. Remove the main bearing caps.
9. Carefully lift the crankshaft out of the block so that the thrust bearing surfaces are not damaged.
Handle the crankshaft with care to avoid possible fracture or damage to the finished surfaces.
Cleaning
Handle the crankshaft with care to avoid possible fractures or damage to the finished surfaces. Clean the crankshaft with solvent, then blow out all oil passages with compressed air.
Inspection
Inspect main and connecting rod journals for cracks, scratches, grooves or scores.
Measure the diameter of each journal in at least four places to determine out-of-round, taper or undersize condition (Fig. 88).
On engines used with a manual shift transmission, check the fit of the clutch pilot bushing in the bore of the crankshaft. The bushing is pressed into the crankshaft and should not be loose. Inspect the inner surface of the bushing for wear or a bell-mouth condition. Check the ID of the bushing (Fig. 89). Replace the bushing if it is worn or damaged.
Inspect the pilot bearing, when used, for roughness, evidence of overheating or loss of lubricant. Replace it if any of these conditions are found.
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Dress minor imperfections with an oil stone. If the journals are severely marred or exceed the wear limit, they should be refinished to size for the next undersize bearing.
Refinishing journals
Refinish the journal to give the proper clearance with the next undersize bearing. If the journal will not’~ clean up to give the proper clearance with the maximum under-size bearing available, replace the crankshaft.
Always reproduce the same journal shoulder radius that existed originally. Too small a radius will result in fatigue failure of the crankshaft. Too large a radius will result in bearing failure due to radius ride of the bearing.
After refinishing the journals, chamfer the oil holes, then polish the journal with a No. 320 grit polishing cloth and engine oil. Crocus cloth may be used also as a polishing agent.
Installation
1. Remove the rear journal oil seal from the block and rear main bearing cap.
2. Remove the main bearing inserts from the block and bearing caps.
3. Remove the connecting rod bearing inserts from the connecting rods and caps.
4. If the crankshaft main bearing journals have been refinished to a definite undersize, install the correct undersize bearings. Be sure the bearing inserts and bearing bores are clean. Foreign material under the inserts may distort the bearing and cause a failure.
5. Place the upper main bearing inserts in position in the bores with the tang fitting in the slot provided.
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