JLG 3246ES Service Manual - Manual (Page 110)

SECTION 4 - HYDRAULICS
4-8 – JLG Lift – 3121166
persist (erratic PUMP PWM%, PUMP CUR around
150A), examine the cabling between the Pump
Motor and Power Module compartment for a
short-circuit (most likely near area where cylinder
retracts between frame side sheets or near pot-
hole mechanism). If the symptoms change, sus-
pect a short-circuited (or mechanically frozen)
pump motor.
A clamp-on ammeter (set for 200A DC) can be
placed on either Pump Motor Cable for verifica-
tion. During Lift Up, the ammeter will read
approximately 150A.
Pump Removal
1. Place the pump/motor assembly on a clean work-
bench.
NOTE: Drain the hydraulic oil by carefully removing the oil
fill plug located on the left side of the hydraulic reser-
voir.
2. Remove the oil tank from the lift cylinder as fol-
lows:
a. Slowly loosen and remove the four bolts that
hold the tank on to the cylinder.
b. Carefully remove the tank from the valve body
taking care not to damage internal pickup
tube or o-ring gasket on tank.
c. Place tank on a suitable work bench or work
area.
NOTE: The filter and bypass are located on the pickup tube
inside the tank.
The filter should be changed once a year.