Nexstar Iii Mechanical Troubleshooting Table - Vanguard CPW 125-4-S Series Operation And Maintenance Manual

6.1.4 NEXSTAR III MECHANICAL
Problem
Jammed cartridge
CRANE MOVES Counter-balance set too low
UNEXPECTEDLY
(boom up and boom down)
Contaminant in cartridge
PTO not engaged
NO FUNCTION
Crane diverter valve not
OPERATES ON
engaged
THE CRANE
Hydraulic tank is low or empty
Vehicle is not running
ALL FUNCTIONS Fast idle not activated
OPERATE
SLOWLY
Filter clogged
Operation time
Unloader valve overridden
EXCESSIVE HEAT
DURING
Undersized hydraulic tank
OPERATION
Jammed cartridge
Counter-balance set too low
CRANE MOVES
(boom up and boom down)
UNEXPECTEDLY
Contaminant in cartridge
PTO not engaged
NO FUNCTION
Crane diverter valve not
OPERATES ON
engaged
THE CRANE
Hydraulic tank is low or empty
TROUBLESHOOTING TABLE
Cause
Table 5. Mechanical Troubleshooting Table
Effect
Try to manually override the valve. If
unable to move stem, cartridge is
jammed.
Adjust the counter-balance out to see if
movement stops.
Valve sticks in certain positions
Check PTO activation light, usually
located in the cab
Is using Auto Crane outriggers, check
the crane diverter valve located at the
outrigger valve
Inspect the hydraulic oil level in the tank
Verify engine is running
If vehicle is manual transmission, verify
fast idle is shown in the LCD screen
Check LCD screen
Crane operation is generally designed
for intermittent duty. 2 hours before oil
gets hot
Check the unloader valve and verify the
manual override is not activated ref.
Page.
Hydraulic tank should be at least 2 x
gpm = gallons. This includes any other
accessories that operate from the same
tank
Try to manually override the valve. If
unable to move stem, cartridge is
jammed.
Adjust the counter-balance out to see if
movement stops.
Valve sticks in certain positions
Check PTO activation light, usually
located in the cab
Is using Auto Crane outriggers, check
the crane diverter valve located at the
outrigger valve
Inspect the hydraulic oil level in the tank
25
Solution
Replace the cartridge
Contact Auto Crane for proper
setting of counter-balance.
Counter-balance valve may need
to be replaced.
See cartridge maintenance for
cleaning procedure
Engage PTO
Engage crane diverter valve
Fill tank to proper level
Start the vehicle
Activate fast idle
Replace filter
Reduce use of crane, increase
hydraulic tank size, or add oil
cooler
Deactivate unloader valve
This is a general rule. Many
factors affect heat: ambient
temperature pressure loss,
operation time. For example, a
smaller tank could be used with
more intermittent use or in cold
environments
Replace the cartridge
Contact autocrane for proper
setting of counter-balance.
Counter-balance valve may need
to be replaced.
See cartridge maintenance for
cleaning procedure
Engage PTO
Engage crane diverter valve
Fill tank to proper level