Manitowoc MLC650, Service Maintenance Manual

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Reference
Only
Manitowoc
Published 09-09-16, Control # 229-09
2-35
MLC650 SERVICE/MAINTENANCE MANUAL HYDRAULIC SYSTEM
2
2
Drum Brake Test
Perform an operational test of each brake weekly.
NOTE: See system pressure specifications in Table 2-1
The electrical connector must be disconnected at
the brake solenoid valves to stall the crane
functions during the test.
1. At the pilot brake and pawl manifold, disconnect the
electrical connector from the solenoid for the brake
being checked.
2. Start and run the engine at low idle.
3. Turn off the park switch on the control console for the
function being checked.
4. At the display, navigate to the diagnostic screen for the
function being checked (see the MLC650 Main Display
Operation F2267 for display navigation instructions).
NOTE: For the front or rear load drum, make sure free-fall
is off.
Monitor the system pressure and pump command
while moving the control handle.
5. Slowly move the control handle for the function being
checked and verify the following:
• Specified system pressure is reached before 50% of
the pump command is reached.
• The brake does not slip.
NOTE: If the brake fails to meet these criteria, it must be
repaired or replaced and retested before operating
with a load.
6. Turn on the park switch on the control console for the
function being checked.
7. Shut off the engine.
8. At the pilot brake and pawl manifold, reconnect the
electrical connector to the solenoid of the brake that was
checked.
Swing Brake Test
Perform an operational test of the swing brake weekly in an
area where the crane can be swung without interference.
NOTE: See system pressure specifications in Table 2-1.
1. Start and run the engine at low idle.
2. Turn off the swing park switch.
3. At the display, navigate to the swing diagnostics screen
and verify the swing park brake is released.
4. Swing the crane by moving the control handle in both
directions and verify the rotating bed swings freely.
5. Move the control handle to the NEUTRAL position and
allow the rotating bed to come to a complete stop.
6. Turn on the swing park switch.
7. At the display, verify the swing park brake is applied.
8. Attempt to swing the crane by moving the control handle
in both directions and verify the following:
• Specified system pressure is reached before 50% of
the pump command is reached.
• The swing brake does not slip.
NOTE: If the brake fails to meet these criteria, it must be
repaired or replaced and retested before operating
with a load.
9. Shut off the engine.
CAUTION
Overheating Hazard!
Do not stall any function for more than 5 seconds.
Damage from overheating can occur to the system
components.
WARNING
Falling Load/Moving Crane Hazard!
If a disc brake slips when the drum brake test is
performed, repair or replace it before placing the crane
back into service. Loads could fall or the crane could
move if the brakes are not operating properly, causing
serious injury.
See the corresponding motor or gearbox manufacturer’s
manual for disc brake repair instructions.
CAUTION
Overheating Hazard!
Do not stall any function for more than 5 seconds.
Damage from overheating can occur to the system
components.
WARNING
Moving Crane Hazard!
If a disc brake slips when the swing brake test is
performed, repair or replace it before placing the crane
back into service. The crane could move if the brakes are
not operating properly, causing serious injury.
See the corresponding motor or gearbox manufacturer’s
manual for disc brake repair instructions.