Note. The crankshaft can only be removed after the engine has been removed from the vehicle. It is further assumed that the flywheel, anti-vibrator, timing chain, oil sump, oil pump and pistons with connecting rods have already been removed.
1. Before to remove a cranked shaft, check up an axial backlash. Install the indicator so that its rod is in line with the crankshaft and touches one of the cranks (see illustration).
14.1. Checking the axial clearance of the crankshaft using an indicator
2. Move the crankshaft to the limit back and set the indicator scale to zero. Then move the crankshaft as far forward as possible and read the indicator. The measured distance is equal to the axial clearance. If its value exceeds the value specified in the specifications of this chapter, it is necessary to check the wear of the thrust surfaces of the crankshaft. If no signs of wear are visible, the clearance can be corrected by installing new bearings.
3. If you don't have an indicator, feelers can be used. Carefully move the crankshaft all the way to the front of the engine. To determine the clearance, insert a feeler gauge between the crankshaft and the front face of the thrust main bearing (see illustration).
14.3. Checking the axial clearance of the crankshaft using a feeler gauge
Note. The thrust bearing is located at the cover N2 (engine 3.8 l) or N3 (engine 3.1 l) main bearing.
4. Check up presence of labels-pointers on covers of radical bearings. They must be numbered consecutively from the front of the engine to the rear. If there are no marks, apply them using special stamps or a center punch (see illustration). Main bearing caps usually have arrows cast on them that point towards the front of the engine (see illustration). Loosen the main bearing cap bolts 1/4 turn one at a time until they can be removed by hand. If studs are used anywhere, make sure they return to their original locations when reinstalling the crankshaft.
14.4a. Using a center punch or special die, mark the main bearing caps to ensure they are seated in their original positions in the block (mark with a punch near the head of one of the bolts) | 14.4b. The arrow on the main bearing cap points towards the front of the engine |
5. When removing the covers from the engine block, lightly tap them with a soft-faced hammer. If necessary, use the bolts as levers when removing the covers. Be careful not to drop the bearing shells if they come out with the covers.
6. Gently lift and remove the crankshaft from the engine. An assistant is needed when performing this operation, since the crankshaft is quite heavy. Install the covers in their original places in the cylinder block and tighten the bolts by hand; while the bearing shells must be in place in the cylinder block and main bearing caps.
7. Remove the rear oil seal from the crankshaft.