Crankshaft Main Bearings - Remove and Install


Removal Procedure

Remove:
- the engine oil pump.
- the crankshaft rear seal. Ensure that the main bearing cap is marked for the correct location and orientation.


- the two setscrews (1) and the main bearing cap (2) from the cylinder block.


- the lower main bearing shell (3) from the main bearing cap (2). Keep the main bearing shell and the main bearing cap together. The lower main bearing shell is a plain bearing that has no oil holes.


For number six main bearing, remove the two thrust washers (4) from the cylinder block. In order to remove the thrust washers (4), use Tooling to rotate the crankshaft in the correct direction. If necessary, push the crankshaft toward the front of the engine or push the crankshaft toward the rear of the engine while you rotate the crankshaft, in order to aid removal. The thrust washers have a locating tab at one end.


Push out the upper main bearing shell (5) with a suitable tool from the side opposite the locating tab. Carefully rotate the crankshaft while you push on the bearing shell.
- the upper main bearing shell (5) from the cylinder block. Keep the bearing shells together. The upper main bearing shell has a groove and two oil holes.

Installation Procedure

Ensure that the main bearing shells are clean and free from wear or damage. If necessary, replace the main bearing shells. Clean the journals of the crankshaft. Inspect the journals of the crankshaft for damage. If necessary, replace the crankshaft or recondition the crankshaft.
Lubricate the crankshaft journal and the upper main bearing shell (5) with clean engine oil. Slide the upper main bearing shell (5) into position between the crankshaft journal and the cylinder block. Ensure that the locating tab for the upper main bearing shell is correctly seated in the slot in the cylinder block. The upper main bearing shell has a groove and two oil holes.

For number six main bearing, ensure that the two thrust washers (4) are clean and free from wear or damage. If necessary, replace the thrust washers. Lubricate the thrust washers (4) with clean engine oil. Slide the thrust washers (4) into position between the crankshaft and the cylinder block. Ensure that the locating tab is correctly seated in the cylinder block.
Install:
- the lower main bearing shell (3) into the main bearing cap (2). Ensure that the locating tab for the lower main bearing shell is correctly seated into the slot in the bearing cap. The lower main bearing shell is a plain bearing that has no oil holes.


Lubricate the crankshaft journal and the lower main bearing shell with clean engine oil. Install the main bearing cap (2) to the cylinder block. Ensure the correct orientation of the main bearing cap. The locating tab for the upper and the lower bearing should be on the same side of the engine. Lubricate the threads of the setscrews (1) with clean engine oil. Lubricate the underside of the heads of the setscrews (1) with clean engine oil.
Install the setscrews (1) to the main bearing cap (2). Evenly tighten the setscrews in order to pull the cap (2) into position. Ensure that the cap is correctly seated. Do not tap the main bearing cap into position as the bearing shell may be dislodged. Tighten the setscrews (1) to a torque of 80 N·m (59 lb ft). Turn the setscrews (1) through an additional 90 degrees. Use Tooling to achieve the correct final torque.

Check the crankshaft end play. Push the crankshaft toward the front of the engine.
- Tooling to the cylinder block and the rear face of the crankshaft. Push the crankshaft toward the rear of the engine. Use Tooling to measure the crankshaft end play. The permissible crankshaft end play is 0.17 mm (0.007 inch) to 0.41 mm (0.016 inch).
- the crankshaft rear seal.
- the engine oil pump.