Fig. 13.7. Connecting measuring instruments when checking the pressure of the hydraulic power steering pump: 1 – thermometer; 2 – adapter MV990993; 3 – pressure relief hose; 4 – pressure gauge МВ990662; 5 – shut-off valve; 6 – adapter MV990994; 7 – high pressure hose; 8 – pump; 9 – tank
1. Disconnect the high pressure hose from the power steering pump and connect the measuring instruments (see Fig. 13.7).
2. Remove air from the hydraulic system and then, with the vehicle stationary, turn the steering wheel several times until the temperature of the working fluid rises to 50–60°C.
3. Start the engine and let it idle.
4. Disconnect the pressure sensor switch connector and connect an ohmmeter to the connector.
5. By smoothly closing the pressure gauge cut-off valve and increasing the working pressure, check the operating pressure of the switch sensor. The nominal pressure is 1.8–2.4 MPa.
6. Open the shut-off valve smoothly and reduce the working pressure; then check the lower threshold of the sensor-switch response pressure. The nominal pressure is 1.0 MPa.
7. Disconnect the measuring instruments and tighten the hydraulic system hoses to a torque of 44 N·m.
8. Remove air from the hydraulic system.