13
308-560
MOTOR WON’T OPERATE (Continued)
TYPE OF PROBLEM
WHAT TO CHECK
If check is OK, go to next check
WHAT TO DO
When check is not OK refer to this column
Follow
Pressure Relief Proce-
dure on
page 13. Remove gun
from hose. Remove pressure
control.
1
. Check leads from motor to be sure they are
securely fastened and properly mated.
1. Replace loose terminals; crimp to leads. Be
sure male terminal blades are straight and
firmly connected to mating part.
Clean circuit board male terminals. Re-
place loose or damaged terminals. Se-
curely reconnect leads.
2. Check for loose motor brush lead connections
and terminals. See page 19.
2. Tighten terminal screws. Replace brushes
if leads are damaged. See page 19.
3. Check brush length which should be 12 mm
(1/2 in.) minimum. See page 19.
NOTE:
The brushes do not wear at the same
rate on both sides of the motor . Check both
brushes.
3. Replace brushes. See page 19.
4. Check for broken or misaligned motor brush
springs. Rolled portion of spring must rest
squarely on top of brush. See page 19.
4. Replace spring if broken. Realign spring
with brush. See page 19.
5. Check motor brushes for binding in brush
holders. See page 19.
5. Clean brush holders. Remove carbon with
small cleaning brush. Align brush leads
with slot in brush holder to assure free verti-
cal brush movement.
6. Check motor armature commutator for burn
spots, gouges and extreme roughness. Re-
move motor cover and brush inspection
plates to check. See page 19.
6. Remove motor and have motor shop resur-
face commutator if possible. See page 27.
7. Check motor armature for shorts using arma-
ture tester (growler) or perform spin test. See
page 17.
7. Replace motor. See page 27.
8. Check pressure control board (301) by substi-
tuting with a good pressure control board. See
page 22.
8. Replace with new pressure control board
(301). See page 22.
Refer to the wiring diagram on
page 38 to identify test points
(TP).
1. Check filter board. Connect volt meter to TP7
and ON/Off switch TP3.Connect a jumper
from TP4 to TP8. Plug in sprayer
. Meter
should read 200 to 250 VAC. Unplug sprayer.
Remove jumper.
1. Temporary bypass to check (Replace filter
board?)
2. Check power supply cord (314). Disconnect
TP1 female (neutral) and TP2 female and
connect volt meter to these leads. Plug in
sprayer. Meter should read 200 to 250 VAC.
Unplug sprayer. Reconnect TP2.
2. Replace power supply cord. See page 20.
3. Check ON/OFF switch (307). Disconnect TP3
and TP4 and connect volt meter to TP3 and
TP4 terminal on the ON/OFF switch. Plug in
sprayer and turn ON. Meter should read 200
to 250 VAC. Turn off and unplug sprayer. Re-
connect TP3.
3. Replace ON/OFF switch. See page 21.
4. Check motor terminal cutoff switch. Connect
volt meter to TP1 female and TP6 female.
Plug in sprayer and turn on. Meter should read
200 to 250 VAC. Turn off and unplug sprayer.
4. Allow motor to cool. Correct cause of over-
heating. If switch remains open after motor
cools, check continuity between TP4 fe-
male and TP5 female with ohmmeter . If
open, replace motor.
5. Check all terminals for damage or loose fit.
Reconnect TP1, TP2, TP3, TP4, TP5, and
TP6 connectors.
5. Replace damaged terminals and recon-
nect securely.