Gradall 534B (9020-7317) Service Manual - Manual (Page 85)

HYDRAULIC RESERVOIR
The reservoir is located on the right side of the
machine. directly in front of the fuel tank. It holds
24 gallons of hydraulic oil. The system holds 40
gallons. The measuring dip stick is a part of the filler
cap. In the filler opening is a wire screen. Oil
returning to the reservoir passes thru a 10 micron
replaceable type filter. As oil is drawn off by the
pumps, it pasees thru a 100 mesh screen.
HYDRAULIC PUMPS
The main pump is a two section tandem pump which
delivers 63 gpm at 2600 rpm. Each of the two sections
is rated at 31.5 gpm. The base section services the
steering and the rear wheel drive. The end section
serves the main control valves for the other circuits.
The tandem pump is mounted with a direct drive
from the transmission. Each section is protected by
a 3000 psi relief valve.
The pilot pump is a one section pump, mounted on
the left side of the engine on the tachometer drive.
The drive turns at l/2 of engine speed. The output of
the pilot pump is 1 to 2 gpm. It is protected by a 500
psi relief valve.
MAIN CONTROL VALVE BANK
The main control valve bank for the sway, tilt, crowd
and lift circuits is located on the floorboard under the
operator’s seat. Each valve plunger is connected to
the operator’s control levers.
The standard valve bank consists of an inlet section
with a built-in adjustable relief valve cartridge rated
at 3000 psi., the four control valves and an end
The tilt control valve has two built in and adjustable
circuit relief valves rated at 3250 psi.
If the auxiliary hydraulic circuit is used for the truss
boom winch, another valve section is added between
the tilt valve and the sway valve.
GRADALL LOED MATERIALS HANDLER 534B SYSTEM OPERATION
9