SHAFT 4M8845 - Caterpillar

Remove Crankshaft
START BY:a. remove flywheel housingb. remove timing gear coverc. remove oil pan plated. remove oil pump The procedure for crankshaft removal is the same on both 3304 and 3306 Engines. The illustration in the procedure which follows is of a 3306 Engine.1. Install the engine on tooling (A) with the crankshaft in a horizontal position and on top. 2. Turn the crankshaft until the timing mark "C" on crankshaft gear (1) is in alignment with the timing mark "C" on camshaft gear (2) as shown in the inset. 3. Remove nuts (4), the connecting rod bolts and connecting rod caps (3) from the connecting rods.
If the piston and connecting rod assemblies are pushed down too far in the cylinder liners, the piston can hit the fuel injection nozzle or the intake exhaust valve which can cause damage to the fuel injection nozzle or the piston.
If the intake and exhaust valves are closed, it can be difficult to push the piston and connecting rod assembly down in the cylinder liner.4. Push the pistons that are not at top center down far enough to clear the crankshaft.5. Remove main bearing cap bolts (5) and main bearing caps (6) from the engine. 6. Remove thrust bearings (7) from the rear main bearing. 7. Install tooling (B) on crankshaft (8) as shown and fasten a hoist to it. Lift the crankshaft straight up from the cylinder block. The weight of the crankshaft for 3304 Engines is 65 kg (143 lb.). The weight of the crankshaft for 3306 Engines is 95 kg (210 lb.). 8. Use tooling (C) and remove crankshaft gear (1) from the crankshaft.
If the bearings are to be removed, put identification marks on them as to their location for installation purposes.
9. If necessary, remove the main bearings from the cylinder block and main bearing caps. If necessary, remove the connecting rod bearings from the connecting rods and connecting rod caps.Install Crankshaft
1. Put the engine in position on tooling (A). If the crankshaft journals and bores for the block and rods were measured at disassembly and found to be within specifications, no further checks are necessary. However, If the serviceman still wants to measure the bearing clearances, Plastigage is recommended. Lead wire, shim stock or use of a dial bore gauge can damage the bearing surface.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 of oil where the Plastigage touches it.... If the main bearing clearances are checked with the engine upright or on its side, the crankshaft must be supported. Use a jack under an adjacent crankshaft counterweight and hold the crankshaft against