Pic. 13.7. Connecting measuring devices when checking the pressure of the hydraulic power steering pump: 1 - thermometer; 2 – adapter МВ990993; 3 - pressure relief hose; 4 - manometer МВ990662; 5 - cut-off valve; 6 – adapter МВ990994; 7 - high pressure hose; 8 - pump; 9 - tank
1. Disconnect the high pressure hose from the power steering pump and connect gauges (pic. 13.7).
2. Remove air from the hydraulic system and then, with the vehicle at a standstill, make several turns of the steering wheel until the temperature of the working fluid rises to 50-60°C.
3. Start the engine and hold the speed (1000±100) min-1.
4. Completely close the shut-off valve on the measuring pressure gauge and measure the maximum pressure generated by the hydraulic power steering pump and check its compliance with the nominal value. The nominal value is 9.8 MPa.
Attention! The shut-off valve should not be closed for more than 10 s.
5. If the maximum pressure does not match the nominal pressure, the pump must be replaced.
6. Check the pressure in the hydraulic system without load with the cut-off valve fully open. The nominal value is 0.3–0.8 MPa.
7. If the obtained pressure value does not correspond to the nominal value, then the cause of the malfunction should be sought in the steering mechanism or hydraulic system hoses.
8. Fully open shut-off valve.
9. Turn the steering wheel all the way to the left or right and measure the holding pressure. The nominal value is 9.8 MPa.
10. If the measured pressure does not correspond to the nominal, replace the steering gear and re-measure the pressure.
11. Disconnect the gauges and tighten the hydraulic hoses to 44 Nm.
12. Remove air from the hydraulic system.