JLG 260MRT Service Manual - Manual (Page 44)

SECTION 2 - PROCEDURES
2-22 – JLG Lift – 3121801
2.14 DRIVE PUMP START-UP PROCEDURE
THE FOLLOWING PROCEDURE SHOULD ALWAYS BE PER-
FORMED WHEN STARTING A NEW PUMP OR WHEN RESTARTING
AN INSTALLATION IN WHICH EITHER THE PUMP OR MOTOR
HAVE BEEN REMOVED FROM THE SYSTEM.
THE FOLLOWING PROCEDURE SHOULD ALWAYS BE PER-
FORMED WHEN STARTING A NEW PUMP OR WHEN RESTARTING
AN INSTALLATION IN WHICH EITHER THE PUMP OR MOTOR
HAVE BEEN REMOVED FROM THE SYSTEM.
THE FOLLOWING PROCEDURE MAY REQUIRE THE MACHINE TO
BE DISABLED (WHEELS RAISED OFF THE GROUND, DRIVE
FUNCTION DISCONNECTED, ETC.) WHILE PERFORMING THE
PROCEDURE IN ORDER TO PREVENT INJURY TO TECHNICIAN
AND OTHER PERSONNEL. TAKE NECESSARY SAFETY PRECAU-
TIONS BEFORE MOVING THE MACHINE.
Prior to installing pump and/or motor, inspect unit(s) for
damage incurred during shipping and handling. Make
certain all system components (reservoir, hoses, valves,
fittings, heat exchanger, etc.) are clean prior to filling with
hydraulic fluid.
Fill reservoir with recommended hydraulic fluid, which
should be passed through a 10 micron (nominal, no
bypass) filter prior to entering the reservoir. The use of
contaminated fluid will cause damage to components,
which may result in unexpected machine movement.
The inlet line leading from the reservoir to the pump
should be filled prior to start-up. Check inlet line for prop-
erly tightened fittings and make sure it is free of restric-
tions and air leaks.
Be certain to fill pump and/or motor housing with clean
hydraulic fluid prior to start-up. Fill housing by pouring fil-
tered oil into upper case drain port.
Install a 0 to 35 bar (0 to 500 psi) pressure gauge in the
charge pressure gauge port to monitor charge pressure
during start-up.
It is recommended that the external control input signal
electrical connections be disconnected at the pump con-
trol until after initial start-up. This will allow the pump to
remain in its neutral position.
“Jog” or slowly rotate prime mover until charge pressure
starts to rise. Start prime mover and run at the lowest pos-
sible RPM until charge pressure has been established.
Excess air may be bled from high pressure lines through
high pressure gauge ports.
DO NOT START PRIME MOVER UNLESS PUMP IS IN NEUTRAL
POSITION (0 DEGREES SWASHPLATE ANGLE). TAKE PRECAU-
TIONS TO PREVENT MACHINE MOVEMENT IN CASE PUMP IS
ACTUATED DURING INITIAL START-UP.
Once charge pressure has been established, increase
speed to normal operating RPM. Charge pressure should
be approximately 20.7 bar (300 psi) minimum. If charge
pressure is incorrect, shut down and determine cause for
improper pressure.
INADEQUATE CHARGE PRESSURE WILL AFFECT THE OPERA-
TOR’S ABILITY TO CONTROL THE MACHINE.
Shut down prime mover and connect external control
input signal. start prime mover, checking to be certain
pump remains in neutral. with prime mover at normal
operating speed, slowly check for forward and reverse
machine operation.
Charge pressure should remain at 20.7 bar to 22.1 bar
(300 psi to 320 psi) minimum during forward or reverse
operation. Continue to cycle slowly between forward and
reverse for at least five minutes.
Shut down prime mover, remove gauges, and plug ports.
Check reservoir level and add fluid if necessary