Manitowoc MLC300 Service And Maintenance Manual

Reference Only
Manitowoc Published 11-22-17, Control # 257-02 2-27
MLC300 SERVICE/MAINTENANCE MANUAL HYDRAULIC SYSTEM
2
REPLACING PRESSURE TRANSDUCERS
Testing a Pressure Transducer
See Figure 2-23 for the following procedure.
Before replacing a pressure transducer, perform the
following test steps to ensure the suspect pressure
transducer is, in fact, faulty.
1. Perform a pressure transducer calibration as instructed
in the MLC300 Main Display Operation Manual.
2. Stop the engine and turn the ignition switch to the RUN
position.
3. Attach an accurate hydraulic pressure gauge to the
gauge coupler at the suspect pressure transducer.
4. If pressure appears on the gauge, bleed the
corresponding system so the gauge reads zero pressure
(see step 9
on page 2-27).
5. Repeat the pressure transducer calibration and check
the pressure on the calibration display with the engine
running at idle. The display reading and the gauge
reading should be the same.
6. Before replacing a pressure sender, check the electric
signal voltage at the sender. It should be 4 mA at zero
pressure.
Replacing a Pressure Transducer
To replace a pressure transducer, perform the following
procedure.
1. Lower all loads to the ground.
2. Move all control handles to OFF and park all crane
functions.
3. Stop the engine.
4. Place a suitable container under the faulty pressure
transducer to catch hydraulic oil leakage.
5. Disconnect the electrical connector from the pressure
transducer.
6. Slowly loosen the pressure transducer only enough to
relieve the pressure.
7. Remove the pressure transducer and discard it and the
oil leakage according to local environmental regulations.
8. Install the new pressure transducer and connect the
electrical connector.
9. Bleed the pressure transducer circuit as follows.
a. Connect a bleed line with a shut-off valve to the
pressure transducer gauge coupler and place the
end of the hose into a suitable container.
b. Open the shut-off valve.
c. With all control handles off, start and run the engine
at low idle.
d. When clear oil flows from the bleed line (no air
bubbles in the oil), close the shut-off valve.
e. Stop the engine.
f. Remove the bleed line from the gauge coupler at
the pressure transducer.
g. Repeat the above steps for each new pressure
transducer.
10. Perform the pressure transducer calibration.
WARNING
High Pressure Oil Hazard!
Do not attempt to remove a pressure transducer until the
following steps are performed. High pressure oil will
exhaust from the pressure transducer ports.
Hot Oil Hazard!
Take precautions to prevent being burned by hot oil.

Manitowoc MLC300 Specifications

General

Brand	Manitowoc
Model	MLC300
Category	Construction Equipment
Language	English