The axial play of the crankshaft is regulated by the installation of thrust half rings in the second bearing of the crankshaft.
The crankshaft is sealed on the front and rear sides with oil seals. The front oil seal is located in a screwed cover, and the rear oil seal is pressed into the engine crankcase and the rear main bearing cover.
Before removing the crankshaft, determine the amount of its axial play in order to purchase oversized thrust washers if necessary. The procedure for measuring the axial displacement of the crankshaft is as follows.
1. Install a dial indicator on the front side of the cylinder block, as shown in illustrations 17.42, and press the crankshaft in the opposite direction with a screwdriver. Reset the dial gauge to zero.
2. Press on the crankshaft with a screwdriver from the opposite side and read the dial gauge. The value of the axial displacement must be between 0.07 and 0.32 mm. Record the measurement result. If it exceeds the allowable wear limit, then oversized thrust washers must be installed during assembly (sometimes only the thrust half rings wear out).
3. Remove the dial indicator.
4. Remove the crankshaft following the engine disassembly procedure.
Attention! We recommend entrusting the turning of the necks and the installation of new inserts to a specialized workshop.
The procedure for installing the crankshaft is indicated in the chapter on engine assembly.
Be sure to install both thrust half rings of the same thickness. Observe the rated tightening torques. Do not forget to turn the crankshaft in order to establish its possible jamming when performing a certain assembly step.
Rear crankshaft oil seal - replacement
The rear oil seal can be removed with the flywheel removed. This may be required when the clutch begins to slip due to oil intrusion from the crankcase.
5. Remove the oil seal with a screwdriver from the crankcase. Be careful not to damage the crankcase or crankcase flange. To facilitate the work, two self-tapping screws can be screwed on both sides of the stuffing box, and then, prying them alternately at the heads, remove the stuffing box.
Check the surface of the crankshaft mating with the seal lip. If, as a result of friction, signs of wear are visible on the surface, then a new oil seal will need to be installed a little deeper into the crankcase.
6. Press a new oil seal with a suitable mandrel into the crankcase. Lubricate the outer surface of the oil seal with engine oil, and the working surface with universal grease. If the surface of the crankshaft on which the oil seal stands is normal, then press the oil seal flush with the surface of the cylinder block. Otherwise, press the stuffing box deeper into the crankcase and make sure that the stuffing box fits snugly over the entire surface.
Front crankshaft oil seal - replacement
The front oil seal is located in the flange in front of the oil pump and can be removed without removing the engine, but the toothed belt must be removed. To remove it, it is better to screw two self-tapping screws into the gland and remove it with a screwdriver and pliers. Lubricate the outside of the new oil seal with engine oil and the work surface with multipurpose grease. Press the oil seal flush with the surface of the block, being careful not to deform it.
24. Timing gear drive
Timing gear parts can be replaced without removing the engine.
When performing the following work, only partial removal of the toothed belt is required, that is, the belt is removed only from the toothed camshaft pulley:
- removal and installation of the cylinder head;
- Removing and installing camshaft and adjusting valve clearances (1.9 liter engine);
- removal and installation of injection pump.
- Complete removal of the toothed belt is necessary when performing the following work:
- removal and installation of the oil pump drive and the oil pump drive chain;
- replacement of the front crankshaft oil seal;
- removal and installation of the water pump.