NOTE: Typical valve block shown
| Pos. | Spare part number | Name |
| 1 | - | Rail |
| 2 | - | Gear shaft |
| 3 | - | Outer bushing |
| 4 | - | Oil bushing |
| 5 | - | Mud seal |
| 6 | - | Input shaft |
| 7 | - | Torsion |
| 8 | - | Retaining ring |
| 9 | - | Oil seal |
| 10 | - | Fluoroplastic ring (PTFE) |
| 11 | - | Steering gear housing |
| 12 | - | Grooves |
| 13 | - | Pinion - gear shaft to outer sleeve |
| 14 | - | Oil seal |
| 15 | - | Gear shaft teeth |
| 16 | - | Bearing |
| 17 | - | Pinion shaft nut |
The valve block is an integral part of the steering gear. The main function of the valve block is to optimize the force on the steering wheel (for example, when parking) due to the operation of the hydraulic booster. The steering gear housing is an integral part of the steering gear assembly.
The steering gear housing has four ports for connecting the pressure line from the power steering pump, the return line to the reservoir, and the pressure lines to each side of the piston. A non-return valve and seal are installed in the port for the pressure line coming from the power steering pump. The valve block consists of an outer sleeve, an input shaft, a torsion bar, and a pinion shaft.
The valve block is located on the same axis as the pinion shaft, which is connected to the steering column via the input shaft. The valve block elements are located in the steering gear housing with a sealed cover. The outer sleeve is located in the main opening of the gear housing. Three annular grooves are made along its outer diameter. Fluoroplastic rings are installed between the grooves, which seal the opening of the gear housing. In each annular groove, radial holes are drilled through the wall of the sleeve. The axial opening of the outer sleeve is bored to the size of the input shaft. In the opening of the sleeve, six slots are machined at an equal distance from each other.
The ends of the slots are closed and do not protrude outward. Radial holes in the outer sleeve are drilled into each slot. The input shaft has two machined planes on its outer end, which provide for the connection of the fork of the intermediate shaft of the steering column. The planes ensure that the intermediate shaft is installed in the correct position to maintain the optimum phase angle. The inner end of the input shaft has a projection that mates with a slot in the pinion shaft. The position of the projection in the slot allows for a slight relative rotation of the input shaft and the pinion shaft before the projection touches the wall of the slot. This makes it possible, in the event of a failure of the hydraulic booster, to use the steering manually, thereby avoiding excessive loads on the torsion bar.
Along the circumference of the central part of the input shaft, longitudinal grooves are machined at equal distances from each other. The grooves are located alternately around the input shaft. The torsion bar is attached to the inner part of the input shaft and to the pinion shaft. The torsion bar is connected to the input shaft by means of a drive pin. In the central part, the torsion bar has a smaller diameter than at the ends. The smaller diameter allows the torsion bar to twist under the influence of the torque applied to the steering wheel, depending on the adhesion of the tires to the road surface. The pinion shaft has a projection in the center, which is connected with a projection on the steering rack. The projection on the input shaft enters the groove machined in the upper part of the pinion shaft. The pinion shaft is located in the gear housing and rotates on ball bearings.
(Information obtained from the website: «LRMAN.RU»)
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