Graco 231–406, Series A Instructions-Parts List Manual page 13

TYPE OF PROBLEM
(Continued)
Motor runs and pump strokes,
but output is low or there is no
output. output
Motor runs but pump does not
stroke.
Motor is hot and runs
intermittently.
NOTE: Thaw the sprayer if water or water-based material has frozen in it, by placing it in a warm area. Do not try to
start the sprayer until it has thawed completely. If material hardened (dried) in the sprayer, replace the pump pack-
ings. See pump manual 307–806.
Troubleshooting
WHAT TO CHECK
If check is OK, go to next check
Check for worn spray tip.
Check motor brushes; check for loose leads
and terminals, minimum 10 mm brush
length, broken or misaligned springs, or
brushes binding in holders. See page 14.
Check motor armature for shorts by using an
armature tester (growler).
Check to see if pump continues to stroke
when gun trigger is released. With pump on
and primed, trigger gun momentarily, then
release and engage safety latch. Relieve
pressure, turn off and unplug sprayer.
Check to see if intake valve ball and piston
ball are seating properly.
Check for leaking around throat packing nut
which may indicated worn or damaged
packings.
Defective pressure control transducer.
Check displacement pump connecting rod
pin (20). See page 16.
Check for frozen or hardened material in the
pump (39).
Be sure crank in drive housing rotates; plug
in sprayer and turn on briefly to check. Turn
off and unplug sprayer.
Determine if sprayer was operated at high
pressure with small tips, which causes low
motor RPM and excessive heat build up.
Be sure ambient temperature where sprayer
is located is no more than 90 F and sprayer
is not located in direct sun.
Determine in sprayer was turned on,
pressurized, but not operating for long
periods of time.
WHAT TO DO
When check is not OK refer to this column
Follow Pressure Relief Procedure
Warning, then replace tip. See your
separate gun or tip manual.
Replace parts as needed. See page 14.
Replace motor. See page 17 .
Repair pump. See manual 307–806 for
repair.
Repair pump. See manual 307–806 for
repair.
Tighten the packing nut/wetcup.
Repair pump. See manual 307–806 for
repair.
Replace pressure control transducer. See
page 20.
Replace pin, if missing. Be sure retainer
spring (35) is fully in groove all around
connecting rod. See page 16.
Thaw. See the NOTE below. Plug in sprayer
and turn on. Slowly increase pressure
setting to see if motor starts.
Check drive housing assembly for damage
and replace if necessary. See page 24.
Decrease pressure setting or increase tip
size.
Move sprayer to shaded, cooler area, if
possible.
Turn off sprayer whenever you stop
spraying for a while and relieve fluid
pressure.