Gradall 534B (9020-7317) Service Manual - Manual (Page 116)

In a safe area, drive the Gradall, Loed Materials
Handler and test the inching brake. If it is properly
adjusted you should be able to move the Handler
very slowly. and under full control. Attempt to inch
while turning a sharp turn. If the unit does not
respond smoothly, test and adjust as follows:
G R A D A L L L O E D M AT E R I A L H A N D L E R 5 3 4 B T E S T I N G A N D A D J U S T I N G
HOW TO TEST AND ADJUST
THE INCHING MECHANISM
Make sure the service brakes are properly
adjusted.
Install a 0-5000 psi test gage in the tube coming
from the #1 pump section.
Install a 0-2000 psi test gage in the test port
Located in the front brake lines. Bleed the brake
lines.
Depress the foot pedal to full brake application
It should be 3/4" to 1" from the floor. Adjust the
brake linkage, if needed.
Check the low torque machine switch adjustment.
It is located under the floor plate. This switch
should disengage with the first 1/2" to 1" of brake
pedal movement.
1.
2.
3.
4.
5.
You are now ready to test the inching
components: 6.
Start engine and depress the service brake
foot pedal completely down.
Place gear shift in first gear forward with the
rear wheels straight.
Increase engine power to full rpm.
Back off on the brake pedal until the brake
line gage reads 425 psi. HOLD PEDAL 1N
THIS POSITION.
A.
B.
C.
D.
At the same time the gage on the #1 Pump tube
should read 1100-1300 psi. y over or under,
mechanical adjustment of the inching linkage is
required.
If the test gage reading is over 1300 psi, increase
linkage length to inching valve by adjusting yoke
one turn and repeat test.
If the test gage reading is under 100 psi decrease
the linkage length to inching valve by turning
yoke one turn and repeat test.
After adjustment, test the Materials Handler to
make sure it inches corrective. Remove gages and
recap test ports when test is completed.
7.
8.
9.
10.
NOTE: Inching valve spool should not be
bottomed out against the stop in either direction
8