HYDRAULIC LIFT SYSTEM
Fault:
Boom slow to lift.
Hydralada MEWP lift system is tted with lock valve solenoid cartridge which is powered all the time to allow oil in through a check valve in the lifting direction only.
To lower the boom, the power is interrupted by a microswitch on the lift section of the control valve assmebly allowing the oil to return from the cylinder. These machines are con gured with a ow cartridge which controls the maximum rate of oil ow from the cylinder.
Trouble shoot
If the lift coil on the base of the hydraulic ram is not powered, when trying to lift the boom will be slow and the engine will load up. This is because oil is being put out a ow restrictor.
If there is no power to the Solenoid coil the machine will labour heavily, or may not lift at all.
1. Con rm fault by using the manual lever on the control valve. This illuminates the pedal cable.
2. Disconnect the electrical plug of lift microswitch from the control valve.
3. Use a piece of electrical wire to bridge the two pins in machine side on the plug. This will supply power to the lift coil on the ram.
4. Using the manual lever on the control valve test the boom raises. Note: to lower the electrical jumper must be removed
5. If the the issue is resolved, replace lift switch P/N 32-3704-01.
6. Fault still present, reconnect microswitch check fuse behind oil tank.
7. If fuse is blown then Lift coil on the ram requires replacement.
•
Microswitch on models with Dual power triple pumps has two microswitches tted. The microswitch position for the lift is dependant on the pedal con guration in the platform.
• Fault nding
1. LIFT SWITCH failed in Open circuit not allowing power to the coil
2. Lift fuse blown
3. Coil not energising or failed
4. Cartridge sticking
LIFT CYLINDER BLOCK
LIFT & DUAL
JUMPER WIRE
HYDRAULIC LIFT SYSTEM
Fault:
Boom slow to lift.
Hydralada MEWP lift system is tted with lock valve solenoid cartridge which is powered all the time to allow oil in through a check valve in the lifting direction only.
To lower the boom, the power is interrupted by a microswitch on the lift section of the control valve assmebly allowing the oil to return from the cylinder. These machines are con gured with a ow cartridge which controls the maximum rate of oil ow from the cylinder.
Trouble shoot
If the lift coil on the base of the hydraulic ram is not powered, when trying to lift the boom will be slow and the engine will load up. This is because oil is being put out a ow restrictor.
If there is no power to the Solenoid coil the machine will labour heavily, or may not lift at all.
1. Confirm fault by using the manual lever on the control valve. This elminates the pedal cable.
2. Disconnect the electrical plug of lift microswitch from the control valve.
3. Use a piece of electrical wire to bridge the two pins in machine side on the plug. This will supply power to the lift coil on the ram.
4. Using the manual lever on the control valve test the boom raises. Note: to lower the electrical jumper must be removed
5. If the the issue is resolved, replace lift switch P/N 32-3704-01.
6. Fault still present, reconnect microswitch check fuse behind oil tank.
7. If fuse is blown then Lift coil on the ram requires replacement.
Microswitch on models with Dual power triple pumps has two microswitches tted. The microswitch position for the lift is dependant on the pedal con guration in the platform.
•3 Pedal platfrom machines RH switch
•6 Pedal platfrom machines LH switch
Fault nding
1. LIFT SWITCH failed in Open circuit not allowing power to the coil
2. Lift fuse blown
3. Coil not energising or failed
4. Cartridge sticking
JUMPER WIRE
