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SECTION 4 - BOOM & PLATFORM
Troubleshooting
Problem
1. Shaft rotates slowly or not at all
2. Operation is erratic or not responsive
3. Shaft will not fully rotate
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Table 4-1. Troubleshooting
Cause
a. Insufficient torque output
b. Low rate of fluid flow
c. Control or counterbalance valve has
internal leak
d. Piston and/or shaft seal leak
e. Corrosion build-up on the thrust surfaces
f. Swollen seals and composite bearings
caused by incompatible hydraulic fluid
a. Air in actuator
a. Twisted or chipped gear teeth
b. Port fittings are obstructing the piston
Solution
a. Verify correct operating pressure. Do not
exceed OEM's pressure specifications. Load
may be above maximum capacity of the
actuator.
b. Inspect ports for obstructions and
hydraulic lines for restrictions and leaks.
c. Disconnect hydraulic lines and bypass
valve. Leave valve ports open and operate
the actuator through housing ports (do not
exceed OEM's operating pressure). The
valve must be replaced if a steady flow of
fluid is seen coming from the valve ports.
d. Remove the plug and the housing's valve
ports. Operate the actuator through the
housing ports. Conduct the internal leak-
age test as described in the Testing section
on page 24 of this manual.
e. Re-build the actuator. Remove all rust
then polish. Replacement parts may be
needed.
f. Re-build the actuator. Use fluid that is
compatible with seals and bearings.
a. Purge air from actuator. See bleeding
procedures.
a. Check for gear binding. Actuator may not
be able to be re-built and may need to be
replaced. Damage could be a result of over-
load or shock.
b. Check thread length of port fittings. Fit-
tings should during stroke not reach inside
the housing bore.
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Table of Contents
Troubleshooting
