Counterbalance Valves; Steering Relief Valves - Upright MX19 Service And Parts Manual

Hydraulics
C
OUNTERBALANCE
1. Operate the work platform for 10-15 minutes to bring the hydraulic oil up to normal operating tempera-
ture.
2. Remove the gauge port cap and install the pressure gauge assembly.
3. Lift work platform and block front wheels off ground.
4. Loosen the locknuts on Counterbalance Valves.
5. With the machine fully powered up depress the DRIVE button on the upper control box, depress the
interlock lever and slowly pull the control lever to REVERSE to drive the wheels.
6. Adjust the Forward Counterbalance Valve by turning the adjustment screw until the pressure gauge
indicates 83 bar (1200 psi).
7. Slowly push the Control Lever to FORWARD to drive the wheels.
8. Adjust the Reverse Counterbalance Valve by turning the adjustment screw until the pressure gauge
indicates 83 bar (1200 psi).
9. Check the settings by slowly moving the Control Lever FORWARD, then REVERSE, checking the
gauge to ensure pressures are properly set. Re-adjust as needed.
10. Tighten locknuts on valves to 8N-m (6 ft-lbs). Remove blocks and lower work platform to ground.
11. Reconnect the red Control Cable wire to terminal #9.
12. Remove the gauge from the gauge port and re-install cap.
13. Check for proper operation of the drive system and brake.
S
TEERING
1. Operate the work platform for 10-15 minutes to bring the hydraulic oil up to normal operating tempera-
ture.
2. Install gauge in the gauge port.
3. Loosen locknut or remove cover on the Steering Relief Valve and turn adjusting screw counter-clock-
wise two full turns.
4. While one person holds the Steering Switch to steer right or left, slowly turn the Steering Relief Valve
adjusting screw clockwise to increase the pressure until the gauge reads 69 bar (1000 psi).
5. Tighten locknut or replace Steering Relief Valve cover and torque to 8N-m (6 ft-lbs).
6. Remove gauge and replace cap.
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V
ALVES
R V
ELIEF ALVES
Section 3 - Service & Repair
503727-002