Valve Unit Leak Check
Valve Unit Leak Check126 Series
This check should be performed if an internal leak in the valve unit causes a pressure drop in the system and illumination of the warning lamp. Pressure tester kit No. 126589022100 is required for performing this check.
1. Release oil system pressure as described in step 1 under ``Pressure Regulator Test.''
2. Disconnect pressure line from pressure regulator.
3. Connect pressure gauge with distributor, pressure test line and vent screw between pressure regulator and pressure line.
4. Disconnect adjusting switch level controller pressure line and control pressure line from adjusting switch and close with vent screw at adjusting switch.
Fig. 3 Valve unit adjusting switch:
5. Move adjusting switch, Fig. 3, into ``N'' position.
6. Start and run engine until pressure regulator cut-out pressure is reached (refer to ``Pressure Regulator Test'' for specifications), then stop engine and observe pressure gauge. Pressure should not drop more than 15 bar (218 psi) in 30 minutes. To stabilize system pressure, it may be necessary to pressurize system several times.
7. Repeat step 6 with adjusting switch in ``S'' position, then in ``H'' position.
8. If leakage does not exceed specifications in ``N'', ``S'' and ``H'' positions, a properly sealed pressure regulator and adjusting switch are indicated.
9. If leakage exceeds specifications in all three positions, a leaking pressure regulator is indicated.
10. If leakage exceeds specifications in one or two positions, a leaking adjusting switch is indicated.