Manitowoc MLC300 Service And Maintenance Manual

Reference Only
Manitowoc Published 11-22-17, Control # 257-02 2-33
MLC300 SERVICE/MAINTENANCE MANUAL HYDRAULIC SYSTEM
2
There is no physical way to check the disc brakes for any of
the following:
• Travel
• Drums 1, 2, 3, 4, and 6
• Swing
An operational test of each brake must be performed weekly.
Perform this test in an area where the crane can operate
without interference.
See Figure 2-26
for the location of the brake solenoid valves.
See the system pressure specifications in Table 2-1
and
Table 2-2
. Perform the disc brake operational test as follows.
1. Disconnect the electrical connector from the solenoid
valve for the brake being checked.
2. Turn off the Park switch on the control console for the
brake being checked.
3. Start and run the engine at low idle.
4. At the main display, navigate to the Control Information
Screen for the function being checked (see the MLC300
Main Display Operation Manual).
NOTE: For the load drums equipped with Free Fall, make
sure Free Fall is off.
Monitor system pressure and pump command on
the corresponding control information screen while
moving the control handle.
5. Slowly move the control handle for the brake being
checked and verify the following:
• The specified system pressure is reached before
50% pump command is reached.
• The brake does not slip.
If the brake fails this test, it must be repaired or replaced
and retested before placing the crane back into
operation.
6. Turn on the Park switch on the control console for the
function being checked.
7. Stop the engine.
8. Connect the electrical connector to the solenoid valve
for the brake being checked.
FREE FALL BRAKE OPERATIONAL TEST
Perform this test in an area where the crane can be operated
without interference.
1. Turn on free fall for the drum being tested. See the
MLC300 Operator Manual for the procedure.
2. Lift a single line pull load of 16 674 kg (36,760 lb)
approximately 305 mm (12 in) off the ground.
3. Apply the free fall brake pedal and watch the load for
one minute.
4. The load must not lower.
5. If the load lowers, the brake must be repaired or
replaced by a qualified technician.
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 disc brake operational test is
performed, repair or replace it before placing the crane
back into service. Loads could fall or the corresponding
crane functions could move uncontrolled if the brakes are
not operating properly.
See the corresponding motor or gearbox manufacturer’s
manual for disc brake repair instructions.
DANGER
Falling Load Hazard!
The free fall brake will not hold the load if the brake discs
are worn. To prevent the load from falling, perform an
operational test of each free fall brake weekly and service
the brake if needed.
If any deterioration in free fall brake performance is
observed by the operator, have the corresponding brake
repaired or replaced immediately.
Do not operate a drum in free fall if the brake is not
operating properly.
Do not attempt to lower the single line pull load given in
step 2
below using the free fall brake. Brake damage
could occur. Free fall lowering is limited to 8 165 kg
(18,000 lb) per the capacity chart.

Manitowoc MLC300 Specifications

General

Brand	Manitowoc
Model	MLC300
Category	Construction Equipment
Language	English