Checking the rocker arms
1. Check the surface of the valve rocker roller, replace the rocker if there is local wear, damage, scuffing;
2. Check the rotation of the roller and replace the rocker arm if there is any binding or excessive play.
3. Check the surface condition of the rocker pusher (point of contact with the end face of the valve stem) for damage or scratches. Replace rocker if significant wear is found.
Leak test and cleaning of hydraulic lifters
Attention:.
- The hydraulic compensator is a precision part. Keep dust, dirt and other foreign particles out of it.
- Do not disassemble the hydraulic lifter.
- When flushing the hydraulic compensator, use only clean diesel fuel.
1. Prepare three containers ("A", "IN" And "WITH") with enough clean diesel fuel (about 5 liters), to fully submerge the hydraulic compensator when vertical.
2. Place the hydraulic lifter in the container "A" and clean it outside. If deposits are difficult to remove, use a nylon brush.
3. Cleaning the internal cavities of the hydraulic compensator.
- A) Immerse the hydraulic lifter in a container "IN", as it shown on the picture.
- b) Slightly pressing down the steel inner ball of the hydraulic lifter with a special rod, at the same time move the plunger up and down (5-10 times), until the plunger moves smoothly. As a result, plunger sticking will be eliminated and contaminated oil will be removed.
Attention: the steel ball spring is weak, so the performance of the hydraulic compensator may deteriorate if the rod is pressed hard when air is removed.
Note: If the plunger remains stationary or another mechanism failure is found, replace the hydraulic compensator.
- V) Remove the hydraulic compensator from the container, then lightly press the steel ball to force the plunger to push the diesel fuel out of the pressure chamber.
Attention: make sure that the oil hole in the body of the hydraulic compensator is directed towards the container "IN".
- G) Repeat the operations according to p.p. A) - V) again to complete flushing.
4. Removal of air from the hydraulic compensator.
- A) Immerse the hydraulic lifter in a container "WITH" plunger up.
- b) Slightly pressing down the steel inner ball of the hydraulic lifter with a special rod, at the same time move the plunger up and down (four or five times) to remove air until the plunger moves smoothly.
Note: use of special tools (stoppers) to compress the hydraulic compensator facilitates the process of removing air.
Attention: the steel ball spring is weak, so the performance of the hydraulic compensator may deteriorate if the rod is pressed hard when air is removed.
- V) Remove the special tool from the hydraulic lifter. Click on the plunger. If it is difficult to move the plunger, then the hydraulic compensator is in good condition. If the plunger moves freely, then the air removal operation must be repeated. If after that the plunger moves freely, then replace the hydraulic compensator.
Attention: After completing the bleed operation, install the hydraulic compensator vertically upwards to prevent diesel fuel from escaping.
5. After carrying out the operation to remove air, install the hydraulic compensator in a special tool (stand for checking the tightness of the hydraulic compensator).
Note: when installing the hydraulic compensator on the test bench, use the adjusting nut of the bench to adjust the device to the height of the hydraulic compensator, as shown in the figure.
6. After the hydraulic compensator plunger has lowered by about 0.2-0.5 mm, measure the time for lowering the plunger by 1 mm. Replace hydraulic compensator if the measured time does not correspond to the nominal value.
- Rated value: 4-20 s (at diesel fuel temperature 15-20°C)