Oshkosh Corporation JERR-DAN 20NGADF6T-LP, Operation And Safety Manual

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Section 6 - Maintenance
5376000207 6-13
6.7 TROUBLE SHOOTING
You probably won’t require anything but preventive maintenance to keep your Jerr-
Dan 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
b. Low oil level
c. Blocked or restricted hose
d. Dirty hydraulic oil
e. Hydraulic pump worn
f. Frozen hydraulic lines
a. Speed up engine
b. Check level and fill with the
specified oil
c. Inspect: remove blockage
d. Drain, flush and refill with
clean oil, replace filter
e. Rebuild or replace
f. Thaw and remove water
Valve leaks a. Defective seals a. Inspect and replace
Cylinder leaks a. Defective seals or rods a. Inspect and replace
Erratic cylinder
function a. Air in the system
b. Defective pump (pulsating)
a. Cycle hydraulic system 10 to
15 times to remove air
b. Replace if necessary
Remote hand
controller fails to
respond a. Electric power turned off a. Turn on CONTROL power
switch in cab
Electric Control
Switches fail to
respond a. Electric power turned off
b. Electric circuit wiring
a. Turn on CONTROL power
switch in cab
a. Check/repair electrical wiring
circuit problem.