Manitowoc National Crane 600H User Manual

07-03-19 Control # 091-09 6-7
600H SERIES OPERATOR MANUAL MAINTENANCE CHECKLIST
National Crane
6
Cylinders drift
Not getting oil to cylinders. Clean and replace as required.
Worn or damaged piston seals. Replace as required.
Air in hydraulic oil. Cycle crane cylinder to remove air.
Loose holding valve. Tighten valve.
Dirt in holding or check valve. Clean valve.
Hoist will not lift or hold
load.
Load too heavy. Change to applicable multipart reeving.
Relief valve setting too low. Check and adjust if required.
Motor worn excessively. Replace motor.
Counterbalance valve defective or leaking. Clean and replace as necessary.
Anti-two-block system defective. Repair anti-two-block system.
Brake worn out. Repair or replace brake.
Hoist gearbox heats.
Gearbox grease low. Check and fill as required.
Duty cycle too high. Reduce cycle time or speed of Hoist.
Boom chatters during
extension/retraction or
doesn't proportion properly.
Boom sections need lubrication. Grease boom.
Wear pads not shimmed correctly. Re-shim as described in boom assembly section.
Worn wear pads. Replace pads.
Extension cables out of adjustment. Readjust cables and tension properly.
Extend or retract cables broken. Disassemble, inspect, and replace cables.
Boom will not extend.
Proportioning cables not attached. Reconnect, replace and/or adjust cables.
Anti-two-block system shut down. Lower hook, and extend load.
Defective anti-two-block system Repair ATB if defective.
System is in a state of
constant cut-out.
Blown fuse at the crane console. Replace fuse.
ATB switch open. Ensure that ATB switch is closed.
System cuts out too early or
too late.
RCL programmed wrong. Reprogram RCL with correct lift values.
Jib Jack Troubleshooting
Will not lift load.
No oil in system.
Release valve not closed.
Add oil to reservoir.
Turn handle clockwise tightly.
Will lift load only part way. Oil level low. Add oil to reservoir tank.
Will lift load but will not
hold.
The following valve or valves leaking.
a. Suction valve
b. Delivery valve
c. Release valve
Replace jack
Packings worn or damaged. Replace jack
Jack will not lower.
Release valve stuck, probably dirt or
foreign matter.
Transfer load then replace dirty oil, flush oil
reservoir with non-flammable solvent.
Poor lifting.
Dirty oil.
Air in hydraulic system.
Change oil.
Purge air from system.
Poor pumping action. Oil seal for pump unit worn or damaged. Replace jack.
Condition Possible Cause Possible Solution

Manitowoc National Crane 600H Specifications

General

Brand	Manitowoc
Model	National Crane 600H
Category	Construction Equipment
Language	English