309044
13
Advanced Troubleshooting
General Problem: Output is Low or Fluctuating
SPECIFIC PROBLEM
CAUSE
SOLUTION
Pump cycles, but output is low
or surging.
See
Basic Troubleshooting
page 8.
Pump valves are worn.
Check for worn pump valves as follows:
Prime sprayer with paint. Trigger spray gun
momentarily. When spray gun trigger is
released, pump should cycle momentarily
and stop. If pump continues to cycle, pump
valves may be worn.
See
Pump Service
on page 23.
Spray–Prime/Drain valve is leaking.
Check Spray–Prime/Drain valve for debris
trapped on seat and for worn parts. Torque to
185 in-lb (21 N
S
m). Replace if parts are worn.
See
Spray–Prime/Drain Valve Kit
on
page 28.
Voltage from electrical outlet is too low. Low
voltages reduce sprayer performance.
Check voltage of outlet. Meter must read
85 to 130V AC.
Reset building circuit breaker or replace
building fuse.
Repair electrical outlet or try another outlet.
Extension cord is too long or not a heavy enough
gauge.
Replace extension cord.
See
Grounding and Electrical
Requirements
on page 6.
Leads from motor to control board are damaged,
loose, or overheated.
Be sure terminals are centered and firmly
connected. Inspect wiring insulation and
terminals for signs of overheating, and
replace any loose terminals or damaged
wiring. Securely reconnect terminals.
Motor brushes are worn.
NOTE:
Brushes do not wear at the same rate on
both sides of motor. Check both brushes.
Check length of brushes. Brush length must
be 0.25 in. (6.4 mm) minimum. Replace
motor if brushes are worn.
See
Motor Kit
on page 18.
Motor brush springs are broken.
Replace motor if springs are broken.
See
Motor Kit
on page 18.
Motor brushes are binding in brush holders.
Clean brush holders, remove carbon dust
with small cleaning brush.
Motor stops before sprayer reaches correct
pressure (stall pressure is too low).
Replace pressure control switch.
See
Pressure Control Switch Kit
on
page 22.
Motor armature is shorting.
Check for shorts using armature tester
(growler), or perform spin test (see
Motor
Diagnostics
on page 16). Replace motor if
shorts are evident.
See
Motor Kit
on page 18.
Control board is damaged.
CAUTION:
Do not perform control board
diagnostics until you have determined that the
armature is good. A bad motor armature can burn
out a good control board.
See
Control Board Diagnostics
on page
16, and replace control board if damaged.
See
Control Board Kit
on page 17.
