MIRROR 2204050 - Caterpillar

Remove And Install Crankshaft Main Bearings
Start By:a. remove piston cooling jets If possible, removal of the oil pan will make crankshaft main bearing removal and installation easier. See the topic, Remove Oil Pan. The oil pan was removed for photo purposes. The crankshaft main bearings can be removed without removing the oil pan.1. Drain the oil from the oil pan. 2. Use tool (A) to turn the engine and move counterweights (1) in position for removal. Remove counterweights (1) from the crankshaft through the side of the cylinder block.3. Use tool (A) to turn the engine and move the connecting rod bearing surface (journal) to the top center position. 4. Use tool (B) and loosen the four bolts that hold the main bearing cap in position.5. Hold the main bearing cap in position with a pry bar and remove the bolts.6. Remove the bearing caps through the side of the engine. The weight of the bearing cap is 18 kg (40 lb). 7. Remove the lower bearing half (2) from bearing cap (3). 8. Remove thrust plates (4) from each side of the center main bearing.
If the crankshaft is turned in the wrong direction when removing the upper bearing half, the tab of the bearing will be pushed between the crankshaft and cylinder block. This can cause damage to either the crankshaft, or the cylinder block, or both.
On the center main journal that has no oil hole, put a thin piece of soft material that will not damage the crankshaft journal against the end of the bearing, opposite the tab. Hit the bearing with the soft material until the tab of the bearing is free from the cylinder block. Remove the upper half of the main bearing. 9. Install tool (C) in the oil hole in the crankshaft journal and remove upper main bearing halves (5) as the crankshaft is turned and the bearing is moved out of the cylinder block. The following steps are for installation of the crankshaft main bearings.
Make sure the upper and lower halves of the bearings are installed so the bearing tabs fit into the notch in the cylinder block and bearing caps.
Install the main bearings dry when the clearance checks are made. Put clean engine oil on the main bearings for final assembly.10. Install tool (B) in the oil hole of the crankshaft. Put upper bearing half (5) (half with oil hole) in position on the crankshaft. Use tool (A) to turn the engine and push the bearing half in position with tool (B).11. Make sure bearing caps (3) are clean and install lower bearing halves (2) in the caps.
Do not use an impact wrench to tighten the bolts the additional 210 5°.
The serviceman must be very careful to use Plastigage correctly. The following points must be remembered:- Make sure that the backs of the bearings and the bores are clean and dry.- Make sure that the bearing locking tabs are properly seated in their slots.- The crankshaft must be free