
Troubleshooting
311990F
11
Motor runs and pump
strokes
1.
Prime Valve Open.
Close prime valve.
2.
Paint supply.
Refill and reprime pump.
3.
Intake strainer clogged.
Remove and clean, then reinstall.
4.
Suction tube leaking air.
Tighten nut. Check o-ring on tube.
5.
Intake valve ball and piston ball
are seating properly.
See Pump Manual 312015. Strain paint before
using to remove particles that could clog pump.
6.
Leaking around throat packing
nut which may indicate worn or
damaged packings.
See Pump Manual 312015.
7.
Pump rod damaged.
See Pump Manual 312015.
Motor runs but pump does
not stroke
1.
Displacement pump pin dam-
aged or missing.
Replace pump pin if missing. Be sure retaining
spring is fully in groove all around connecting
rod. See page 12,
Displacement Pump
Replacement
.
2.
Connecting rod assembly for
damage.
Replace connecting rod assembly. See page
12,
Displacement Pump Replacement
.
3.
Gears or drive housing.
Inspect drive housing assembly and gears for
damage and replace if necessary. See page
14,
Drive Housing Replacement
.
Motor is hot and runs
intermittently
1.
Be sure ambient temperature
where sprayer is located is not
more than 115°F (46°C) and
sprayer is not located in direct
sun.
Move sprayer to shaded, cooler area if
possible.
2.
Motor has burned windings indi-
cated by removing positive (red)
brush and seeing burned adja-
cent commutator bars.
Replace motor. See page 26,
Motor
Replacement
.
3.
Tightness of pump packing nut.
Overtightening tightens packings
on rod, restricts pump action and
damages packings.
Loosen packing nut. Check for leaking around
throat. Replace pump packings if necessary.
See pump manual 312015.
Problem
What To Check
(If check is OK, go to next check)
What To Do
(When check is not OK, refer to this column)