5.9.2. Replacement of hydrocompensators of gaps in the mechanism of the drive of valves

Hydrocompensators of gaps in the mechanism of the drive of valves represent self-regulating support of the press levers transferring effort from the camshaft to valves and perform function of elimination of gaps in the drive.
Operation of the hydrocompensator is based on the principle of incompressibility of the engine oil which is constantly filling an internal cavity of the hydrocompensator during the operation of the engine and moving its plunger at emergence of a gap in the valve drive, providing continuous contact of the lever of the drive of the valve with a camshaft cam without gap. Thanks to it need of adjustment of valves at maintenance disappears.
Practically all malfunctions of hydrocompensators diagnose on the characteristic noise published by the gas-distributing mechanism on various power setting.
For replacement of hydrocompensators the head of the block of cylinders can be not removed from the engine. It is enough to remove the camshaft case only. However laying of a head of the block is recommended to be replaced after that surely new as the case of the camshaft and a head of the block are attached to the block by the same bolts and at a repeated inhaling of bolts old laying of a head of the block can not provide tightness of connection.
It will be required to you: keys "on 10", "on 13".

Perform work in 15–30 min. after an engine stop that oil pressure in hydrocompensators decreased.

1. Uncover a head of the block of cylinders (see. "Replacement of laying of a cover of a head of the block of cylinders").
2. Turn off a fastening nut...
3.... remove from a hairpin a yoke with the holder...
4.... also take the hydrocompensator.

The hydrocompensator is installed in a head nest with a small tightness and can be easily taken without use of any tool.

5. Similarly remove other yokes and take hydrocompensators.
6. Examine hydrocompensators: on the cylindrical working surfaces of hydrocompensators there should not be zadir or scratches. Measure by a micrometer outer diameters of hydrocompensators (tab. 5.4).

Table 5.4 Nominal and repair sizes of hydrocompensators

7. Examine nests under hydrocompensators in a block head. On their surfaces risks, scratches, teases, excessive unilateral wear are not allowed. Measure diameters of nests under hydrocompensators in a head of the block of cylinders, if necessary grind landing nests.
8. Calculate on a difference of the sizes gaps between hydrocompensators and nests in a head. For new details gaps have to make 0,023–0,060 mm.
9. Grease the new hydrocompensator and a nest in a head of the block of cylinders with engine oil and install the hydrocompensator in a nest.
10. Similarly install other hydrocompensators.

After replacement of the hydrocompensator at the first start-up the engine can until work short time with the increased noise level until the hydrocompensator is pumped over.