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5-376-000094
REV. 3 - 03/10
Section III: Maintnenace
Page 83
TROUBLE SHOOTING
You probably won’t require anything but preventive maintenance to keep
your HDR running, however, the following chart should help you isolate and
correct minor problems if they occur with use. Any service work on the
hydraulic system should be performed by qualified mechanics.
HYDRAULIC SYSTEM
Problem
Cause
Solution
Slow operation
a. Low engine RPM
a. Speed up engine
b. Low oil level
b. Check level and fill with the
specified oil
c. Blocked or restricted hose c. Inspect: remove blockage
d. Dirty hydraulic oil
d. Drain, flush and refill with
clean oil, replace filter
e. Hydraulic pump worn
e. Rebuild or replace
f. Frozen hydraulic lines
f. Thaw and remove water
Valve handle sticks
a. Insufficient lubrication
a. Lubricate per lube chart
tight or frozen
b. Broken centering spring
b. Inspect, clean or replace
or clogged with foreign
material
Valve leaks
a. Defective seals
a. Inspect and replace
Cylinder leaks
a. Defective seals or rods
a. Inspect and replace
Erratic cylinder
a. Air in the system
a. Cycle hydraulic system 10 to
function
15 times to remove air
b. Defective pump (pulsating) b. Replace if necessary
Remote hand
a. Electric power turned off
a. Turn on CONTROL power
controller fails to
switch in cab
respond
b. Discharged battery
b. Charge battery
c. Defective battery
c. Replace
d. Emergency - Off switch
d. Release/pull switch on
depressed
transmitter
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