TM 9-4910-707-14&P
TROUBLESHOOTING
PROBLEM
CAUSE
REMEDY
1. Reset circuit breaker - should be at least
1. Circuit Breaker overloaded
A. Motor fails to
30 AMPS
start with switch
2. Defective switch or electric
in "on" position
2. Check switch for open or defective switch -
connection
repair connection or replace switch
3. Electric motor malfunction
3. Clean motor commutator or replace motor
assembly.
1. Check chuck and chuck jaw rollers or
1. Worn or dirty chuck jaw
B. Chuck fails to
rollers
allen screws for wearing-or chipping -
hold rim
clean or replace worn parts
2. Chuck jaws not expanding
2. Clean adapter cone threads and check
when adapter cone is
cone ramps for nicks or damage - repair
ramps or replace cone
engaged
3. Clean and lubricate screw threads or
3. Dirty or broken chuck
replace broken screw (broken screw pro-
screw
bably caused by chucking with red chuck
roller in wrong position - see chucking
decal on machine)
4. Pressure gauge malfunction
4. Check pressure gauge - no lead gauge pressure
should be 150-2-00 PSI - replace-gauge
1. Replace control cable
1. Broken control cable
C. Tire will not
raise or rotate
2. Check boom hydraulic cylinder for internal
2. Boom control cylinder mal-
leakage - replace seals inside cylinder or entire
function problem could show
cylinder
as lack of power or speed
3. Hydraulic motor malfunction -
3. Clean motor or check for internal or external
leakage - replace motor
problem could show as slow
tire rotation or lack of power
on rotation
1. Hydraulic Pump malfunction
D. Lack of speed or
1. Check pump for internal or external leakage -
replace pump
power on any
function
2. Hydraulic system leakage
2. Check individual power components for
leakage (see D2 and D3 above)
3. Suction line between tank and
pump not air tight or suction
3. Tighten line or clean suction screen
screen plugged - pump will
activate (snapping sound)
4. Bead breaking or mount-
4. Check carriage cylinder for leakage -
replace hydraulic cylinder or replace
demount inoperative or
seals inside cylinder
or malfunction
5. Adjust relief valve (figure 10- lower right)
5. Low hydraulic pressure occurs
to 1800 PSI maximum, check as shown in
mainly on mounting or
Figure 12
remounting of duplex tires
6. Change from oil to transmission fluid in
6. Unit being used primarily outside
hydraulic system
and/or in cold weather situations
1. Replace seals or broken spool valve -
1. Hydraulic control valve malfunction
E. Loss of any in-
dividual function
2. Loosen and retighten mounting screws
2. Sticking valve spools in hydraulic
on control valve unequal mount bolt
control valves - generally due to
tension can distort valve body. Valve
warpage of control valve
body distortion can also occur from
fittings screwed too tight
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