Troubleshooting
311911C 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 hose leaking air. Tighten nut. Check o-rings on swivel.
5. Intake valve ball and piston ball are
seating properly.
See Pump Manual 309250. 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 309250.
7. Pump rod damaged. See Pump Manual 309250.
Motor runs but pump does not
stroke
1. Displacement pump pin damaged or
missing.
Replace pump pin if missing. Be sure retaining
spring is fully in groove all around connecting rod.
See page 13, Displacement Pump Replacement.
2. Connecting rod assembly for dam-
age.
Replace connecting rod assembly. See page 13,
Displacement Pump Replacement.
3. Gears or drive housing. Inspect drive housing assembly and gears for
damage and replace if necessary. See page 15,
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 indicated
by removing positive (red) brush and
seeing burned adjacent commutator
bars.
Replace motor. See page 34, Motor Replacement.
3. Tightness of pump packing nut.
Overtightening tightens packings on
rod, restricts pump action and dam-
ages packings.
Loosen packing nut. Check for leaking around throat.
Replace pump packings if necessary. See pump
manual 309250.
Low air output at gun 1. Air valve at gun may be closed. Turn air valve counter-clockwise to open.
2. Sprayer air regulator may be closed
(FinishPro 395)
Pull to unlock and turn air regulator clockwise to
open.
3. Air connections may be loose. Check all connections for leaking air.
Problem
What To Check
(If check is OK, go to next check)
What To Do
(When check is not OK, refer to this column)