Trouble Shooting; Hydraulic System - Jerr-Dan MPL40 Operation And Maintenance Manual

TROUBLE SHOOTING

You probably won't require anything but preventive maintenance to keep
your MPL40 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
Slow operation
Valve Solenoid(s)
sticking or frozen
Valve leaks
Cylinder leaks
Erratic cylinder
function
Remote hand
controller fails to
respond
5-376-000086
REV. 4 - 07/10
Cause
a. Low engine RPM
b. Low oil level
c. Blocked or restricted
hoses
d. Dirty hydraulic oil
e. Hydraulic pump worn
f . Clutch Pump belt slipping
a. Broken centering spring
or clogged with foreign
material
b. Low Amperage/Voltage
at Solenoid
a. Defective seals
a. Defective seals or rods
b. Dirty or Defective
CounterBalance Valve
a. Air in the system
b. Defective pump
(pulsating)
a. Electric power turned off
b. Not plugged in
c. Faulty Remote Hand
Controller
Section III: Maintenance
Page 81
Solution
a. Speed up engine
b. Check dipstick 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 . Tighten or Replace belt
a. Inspect, clean or replace
b. Check Amperage/Voltage
a. Replace
a. Inspect and replace
b. Clean or Replace
CounterBalance Valve
a. Cycle hydraulic system 10
to 15 times to remove air
b. Replace if necessary
a. Turn on CONTROL power
switch in cab
b. Check plug connection
c. Use Manual Controls
at Rear of Body