Crankshaft Main Bearings

Crankshaft Main Bearings

Special tools, testers and auxiliary items required

• Main Bearing Tool (C-3059A)

• The main bearing caps are not interchangeable and should be marked to insure correct reassembly. Upper and lower bearing halves are not interchangeable.

Removing






- Remove the oil pan. Refer to => [ Oil Pan ] Service and Repair.

- Remove the oil pump pickup tube bolt, tube (1) and seal (2).

- Remove the windage tray bolts and tray (3).






- Identify the main bearing caps (1 through 4) before removal.






- Remove the main bearing caps one at a time. Remove the upper half of the bearing by inserting main bearing tool (C-3059A) (1) into the oil hole of the crankshaft.

- Slowly rotate the crankshaft clockwise, forcing out the upper half of the bearing shell (2).

Installing






The main bearing caps are not interchangeable and are marked to insure correct reassembly. Upper and lower bearing halves are also not interchangeable.


Main bearings are select fit. Refer to => [ Crankshaft Main Bearing Fitting ] Crankshaft Main Bearing Fitting.

• Only one main bearing should be selectively fitted while all the other main bearing caps are properly tightened.

When installing a new upper bearing shell, slightly chamfer the sharp edges from the plain side.

- Lubricate the main bearing with clean engine oil.






- Set the bearing in place, and insert main bearing tool (C-3059A) (3) into the oil hole of crankshaft.

- Slowly rotate the crankshaft counterclockwise allowing the bearing (4) to slide into position. Remove the main bearing tool (C-3059A).

• Lubricate the main bearing cap bolts with clean engine oil before installation.

- Lubricate the lower bearing half with clean engine oil and install the bearing half and main cap. Tighten the bolts finger tight.






- For installing the thrust washers at the number 2 main bearing location, use the following procedure:

- Move the crankshaft forward to its limit of travel. Lubricate with clean engine oil and install the front thrust washer (1) by rolling the washer onto the machined shelf between the number 2 upper main bulk head and crankshaft thrust surface.

- Move the crankshaft rearward to its limit of travel. Lubricate with clean engine oil and install the rear thrust washer by rolling the washer onto the machined shelf between the number 2 upper main bulk head and crankshaft thrust surface.

• The main bearing cap bolts must be tightened in the proper sequence. First the inner main cap bolts, secondly the windage tray bolts, lastly the main cap tie (horizontal) bolts.

- Install the main bearing caps and tighten the inner bolts finger tight.

- Tighten the inner main bearing cap bolts to 20 Nm (15 ft lbs) + 90 degree additional turn.

- Measure the crankshaft end play. Refer to => [ Measuring Crankshaft End Play ] Testing and Inspection.






- Install the windage tray (3) and bolts. Lubricate bolts with engine oil. Tighten the bolts to 28 Nm (21 ft. lbs) + 90 degree additional turn.

- Install a new oil pump pickup tube seal (2) onto the pickup tube.

- Lubricate the pickup tube seal with clean engine oil.

- Install the oil pump pickup tube (1) and bolt. Tighten the bolt to 28 Nm (21 ft lbs).






- Install the main cap tie (horizontal) bolts. Tighten the bolts to 28 Nm (21 ft lbs).

- Install oil pan. Refer to=> [ Oil Pan ] Service and Repair.

- Fill the engine crankcase with the proper oil to the correct level.