Usage:
A. Pump Relief Pressure Tests
1. Remove the 1/2" plug from pump and insert a 3000 psi (20,685 kPa) gauge.
2. With the engine at full throttle turn wheel to its stop and hold it there.
3. The pump should relieve at 2000 psi (13,790 kPa). If relief pressure isn't reached, test other components in steering system or adjust pump.
NOTE: For steering system tests refer to Maintenance Manual 20.
B. Pump Relief Pressure Adjustment
1. If pump relief pressure is below 2000 psi it should be adjusted.
2. To increase pump pressure remove plug (B) and insert proper sized shims until 2000 psi is obtained.
3. To decrease pump pressure remove plug (B) and remove shims until 2000 psi is obtained.
4. If adding or removing shims doesn't alter relief reading, and it is known that other steering components are functioning properly, the pump should be repaired or replaced.
C. Blade Control Valve Pressure Test
1. Insert 3000 psi gauge into front cylinder line: (C).
2. Lower the blade to the "down" position.
3. With the engine at full throttle (2500 RPM) move the blade control lever to the "up" position.
4. The gauge should momentarily peak out at 1250 psi.
5. If a reading appreciably higher or lower (200 psi either way) then 1250 psi is obtained the blade control valve should be adjusted.
D. Relief Adjustment, Blade Control Valve 320A S/N 101-277, 420C S/N 375-407
1. If blade relief pressure is below or above 1250 psi it should be adjusted.
2. Remove plug (D) from blade control valve.
3. To increase pressure REMOVE shims.
4. To decrease pressure ADD shim.
5. If shimming does not alter pressure reading the blade control valve should be repaired or replaced.
E. Relief Adjustment, Blade Control Valve 320A S/N 278 & Up, 420C S/N 408 & Up
1. Remove acorn nut beside base of valve handle.
2. Loosen lock nut behind acorn nut.
3. Turn adjusting screw in to increase pressure, out to decrease.
4. Hold adjusting screw in place and tighten lock nut.
5. Replace acorn nut.
F. Cylinder Leakage Test
1. Raise the blade to the "UP" position.
2. Disconnect the hoses from the rear cylinder ports (E).
3. If more than a trickle issues from the rear ports (E) the cylinders should be repaired or replaced.