Removal
1. Remove the valve covers (see section 4) from the cylinder head.
2. Unscrew the valve rocker arm struts one by one and disconnect the valve rocker arms, supports and support retainers (see illustration). Place each rocker arm assembly separately in labeled plastic bags to avoid confusion when installing the assembly.
5.2. Valve rocker arm parts: 1 - bolt, 2 - valve rocker arm support, 3 - valve rocker arm, 4 - rod guide
3. After removing the rods, store them separately to avoid confusion during installation (see illustration).
5.3 If you are removing more than one rod, store them in a cardboard box with holes to avoid confusion during installation. Pay attention to the sign "Front of the car"
Examination
4. Inspect each rocker arm for signs of wear, cracks or other damage, especially where the rocker arms and valve stems meet.
5. Check the condition of the bearings and bearing faces of all valve rocker arms. Look for signs of metal abrasion, cracks in stress areas and unusual wear patterns. If the valve rocker arms are worn or damaged, replace them with new ones; install new supports at the same time.
6. Make sure that the holes in all valve rocker arms on the valve lifter rod installation side are not clogged.
7. Check the valve lifter rods for cracks and signs of severe wear. Roll each rod across the glass to check for bending.
Installation
8. Apply a coat of motor oil or molybdenum-based grease to the lower ends of the valve lifter rods and install each one in place. Make sure each one is fully seated in its nest.
9. Apply a coat of molybdenum-based lubricant to the ends of the valve stems, the upper tails of the valve lifters and the surfaces of the valve supports to prevent damage to the mating surfaces before the engine oil pressure reaches operating pressure.
10. Apply non-hardening thread lubricant to the rocker arm support bolts. Install the rocker arms, supports, support retainers and bolts; tighten the bolts to the torque specified in the Technical Data section. Once the bolts are tightened, check that the pushrods are seated correctly on the rocker arms.
11. Install the valve covers (see section 4).
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