Crankshaft: Testing and Inspection
1. Clean the crankshaft of the following foreign material:^ Oil
^ Sludge
^ Carbon
2. Clean the oil passages of any obstructions.
3. Inspect the keyway for damage.
4. Inspect the threads.
5. Inspect the bearing journals and thrust surfaces for the following conditions:
^ Cracks
^ Chips
^ Gouges
^ Roughness
^ Grooves
^ Overheating (discoloration)
6. Inspect the bearing inserts for embedded foreign material. Determine the source of the foreign material.
7. Replace the crankshaft if the crankshaft is damaged. Remove slight roughness with a fine polishing cloth. Remove burrs with a fine oil stone.
8. Use a micrometer in order to measure the crankshaft journal taper.
9. Use a micrometer in order to measure the crankshaft journal runout.
10. Note the results if the measurements are within specifications. Use the results later in order to select bearing inserts.
11. Replace the crankshaft if the measurements are not within specifications.
12. Use the following procedure in order to measure the crankshaft flange runout:
a. With the crankshaft installed, place the dial indicator stem outside of the flexplate mounting bolt holes.
b. Set the indicator to 0.
c. Rotate the crankshaft.
d. Record the readings.
e. Replace the crankshaft if the readings are not within limits.
13. If the main bearing high spots are not in line the crankshaft is bent. Replace the crankshaft if the crankshaft is bent.
CAUTION: Do not scrape, shim, or file bearing inserts. If the bearing surface of the insert is touched with bare fingers, the skin oil and acids will etch the bearing surface.
NOTE: Engine bearings are of the precision insert type. They are available for service use in standard and 0.001 inch undersize.
14. Inspect the bearing surfaces for the following conditions:
^ Wear.
^ Gouges.
^ Embedded foreign material. Determine the nature and the source of any foreign material. Inspect the oil pan sludge and residue.
^ Uneven side to side wear. If wear is uneven, check for a bent crankshaft or tapered bearing journals.
15. Inspect the outer surfaces for the following conditions:
^ Wear. Surface wear indicates either movement of the insert or high spots in the surrounding material
^ Discoloration caused by overheating
^ Flattened tangs and wear grooves caused by looseness or rotation
16. Inspect the thrust surfaces for the following conditions:
^ Wear
^ Grooving caused by irregularities of the crankshaft thrust surface
17. Inspect the connecting rods or main bearing bores for the following conditions:
^ Bearing failure. Investigate bearing failure carefully, other than normal wear. Inspect the crankshaft or connecting rod and the bearing bores.
^ Measure the bore for taper and out of round
CAUTION: This bolt is designed to permanently stretch when tightened. The correct part number fastener must be used to replace this type of fastener. Do not use a bolt that is stronger in this application. If the correct bolt is not used, the parts will not be tightened correctly. The system or the components may be damaged.
^ Tighten the bearing cap to specifications in order to inspect the connecting rods or main bearing bores. Start the main bolts by hand. Ensure that the bottom of the cap is parallel to the bottom of the channel. Tighten all of the caps in equal increments. Do not tighten one cap completely at a time. Tighten the bolts to 70 Nm (52 ft. lbs.) in order to fully seat the caps. Loosen the bolts 360 degrees counterclockwise. Tighten the bolts to 20 Nm (15 ft. lbs.), then 40 Nm (30 ft. lbs.).
^ Use the Torque Angle Meter in order to tighten the bolts in steps: 35 degrees+35 degrees+40 degrees for a total of 110 degrees.
18. Install the side main bolts. Tighten the side main bolts to 15 Nm (11 ft. lbs.). Use the Torque Angle Meter in order to tighten the bolts an additional 45 degrees. Measure the bore for taper and for out of round.
19. Inspect the bearing cap bolts. Replace the bolts if the bolts are stretched. Compare the bolt to a new bolt in order to determine if the bolt is stretched.