Graco DT 234140 A Operating instructions

309712
Rev. A
REPAIR
INSTRUCTIONS
KEEP FOR REFERENCE.
Read this and all related manuals for
important warnings and instructions.
DTDTX
Airless Paint Sprayers
3000 psi (207 bar, 20.7 MPa) Maximum Working Pressure
120 Vac
234139, A
234140, A
Table of Contents
Component Function and Identification 3. . . . . . . . . . . .
Grounding 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Repair Information 4. . . . . . . . . . . . . . . . . . . . . .
Spin Test 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Motor Brush Replacement 10. . . . . . . . . . . . . . . . . . . . .
On/Off Switch Replacement 12. . . . . . . . . . . . . . . . . . . .
Pressure Control Repair 14. . . . . . . . . . . . . . . . . . . . . . .
Drive Housing Replacement 17. . . . . . . . . . . . . . . . . . . .
Motor Replacement 18. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Displacement Pump Replacement 19. . . . . . . . . . . . . . .
Technical Data 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Graco Phone Number 20. . . . . . . . . . . . . . . . . . . . . . . . . .
GRACO INC. P.O. BOX 1441 MINNEAPOLIS, MN 55440–1441
COPYRIGHT 2003, GRACO INC.
Graco Inc. is registered to I.S. EN ISO 9001
TI0051c
234139
309639; DTX. . . . . . .
309053; DTX. . . . . . .
Related manuals
309665. . . . . . .
309045; DT. . . . . . .
309717. . . . . . .
309060; DT. . . . . . .

2309712
ADVERTENCIA
L’injection de fluide constitue une lésion grave! Si un fluide haute
pression perce la peau, la blessure peut paraître comme une
«simple coupure». Mais il s’agit bien d’une lésion grave! Consulter
immédiatement un médecin.
Pour éviter les risques d’injection, toujours:
Bloquer le loquet de sécurité de la gâchette à la fin de la pulvérisation.
Pointer le pistolet loin de soi-même et toute autre personne à proximité
Décharger la pression avant de vérifier ou réparer une fuite.
Décharger la pression après la mise hors tension du pulvérisateur ou
à la fin de la pulvérisation.
Ne pas utiliser de composants dont la pression nominale est inférieure
à la pression maximale de service du système.
Ne jamais permettre aux enfants d’utiliser cet appareil. En cas de bles-
sure pour avoir utilisé cet appareil, consulter immédiatement un médecin.
Risque d’incendie et d’explosion imminent pendant la pulvérisation
ou le rinçage à pression de fluides inflammables dans une zone à mau-
vaise circulation d’air et en présence de gaz inflammables pouvant
s’allumer par une flamme nue ou des étincelles.
Pour éviter les risques d’incendie et d’explosion:
Manipuler les fluides à l’air libre ou dans une zone extrêmement
bien aérée.
Ne jamais utiliser de trichloroéthane 1,1,1, de chlorure de méthylène,
d’autres solvants à base d’hydrocarbures halogénés, ni de produits
contenant de tels solvants dans un équipement sous pression en
aluminium. Cela pourrait provoquer une réaction chimique avec risque
d’explosion.
Retirer, éteindre ou déboucher toute source d’inflammation, recouvrir
tout interrupteur mural avec du ruban adhésif. Ne pas fumer dans la
zone de pulvérisation.
Ne jamais remplir le réservoir d’essence lorsque le moteur est chaud
ou en marche.
Mettre à la terre le pulvérisateur, l’objet à pulvériser ainsi que les
seaux de peinture et de solvants.
Tenir le pistolet fermement contre la paroi d’un seau mis à la
terre lorsqu’on pulvérise dans le seau.
N’utiliser qu’un flexible pour peinture pulvérisée sans air.
Ne jamais mettre en marche un moteur dans une zone fermée.
Fluid injection and high pressure hazard: High pressure spray or
leaks can inject fluid into the body.
To help prevent injection, always:
Engage trigger safety latch when not spraying.
Keep clear of nozzle and leaks.
Never spray without a tip guard.
Do PRESSURE RELIEF if you stop spraying or begin servicing
sprayer.
Do not use components rated less than sprayer Maximum
Working Pressure
Never allow children to use this unit.
If high pressure fluid pierces your skin, the injury might look like
“just a cut”. But it is a serious wound! Get immediate medical atten-
tion.
Fire and explosion hazard: Solvent and paint fumes can ignite or
explode.
To help prevent a fire and explosion:
Use only in an extremely well ventilated area.
Eliminate all ignition sources; such as pilot lights, cigarettes and
static arcs from plastic drop cloths. Do not plug or unplug power
cords or turn lights on or off in spray area.
Ground Sprayer, object being sprayed, paint and solvent pails.
Hold gun firmly to side of grounded pail when triggering into pail.
Use only conductive airless paint hose.
Do not use 1,1,1–trichloroethane, methylene chloride, other
halogenated hydrocarbon solvents or fluids containing such
solvents in pressurized aluminum equipment. Such use could
result in a chemical reaction, with the possibility of explosion.
WARNING
MISE EN GARDE
Pueden ocurrir incendios y explosiones cuando se pulveriza fluido in-
flamable o cuando se lava con este tipo de fluido en un área donde la
circulación de aire es deficiente y los vapores inflamables se pueden en-
cender al contacto con el fuego o chispas.
Para prevenir incendios y explosiones:
Use en espacios abiertos o en un área muy bien ventilada.
No utilice nunca tricloretano–1,1,1, cloruro de metileno, u otros di-
solventes a base de hidrocarburos halógenos o fluidos que contengan
tales disolventes en un equipo a presión de aluminio. El uso de estas
sustancias puede provocar una intensa reacción química, con riesgos
de explosión.
Retire, apague o desconecte todas las fuentes de ignición; asegure el
interruptor de la pared con cinta. No fume en el área de pulverización.
Nunca llene el estanque de combustible mientras el motor esté en
marcha o caliente.
Ponga a tierra el pulverizador, el objeto que recibe el chorro pulverizado,
las cubetas de pintura y disolvente.
Sostenga firmemente la pistola a un lado de la cubeta puesta a
tierra cuando dispare dentro de ella.
Use solamente mangueras para pintura conductora sin aire.
Nunca haga andar el motor dentro de un área cerrada.
¡La inyección de fluido en la piel es una lesión seria! Si fluido de
alta presión le penetra la piel, la lesión podría parecer “sólo un
corte”. ¡Es una lesión seria! Consulte de inmediato al médico.
Para prevenir la inyección en la piel, siempre:
Enganche el seguro del gatillo cuando no use el pulverizador.
No apunte la pistola ni a sí mismo ni a los demás.
Alivie la presión antes de inspeccionar o reparar cualquier filtración.
Alivie la presión cuando apague el pulverizador o deje de usarlo.
No use componentes cuya capacidad nominal sea inferior a la
presión máxima de operación del sistema.
No permita que niños usen esta unidad. Si se lesiona usando este
equipo, sométase de inmediato a tratamiento médico.
ADVERTÊNCIA
Poderá ocorrer incêndio e explosão quando for pulverizado ou injetado
líquido inflamável numa área onde houver má circulação de ar; vapores
inflamáveis poderão incendiar-se a partir de uma chama ou fagulhas a
descoberto.
Para ajudar a evitar incêndio e explosão:
Utilize no exterior ou numa área muito bem ventilada.
Não utilize 1,1,1–tricloroetano, cloreto de metileno, outros solventes de
hidrocarbonetos halogenados ou líquidos contendo tais solventes em
equipamento de alumínio pressurizado. Tal utilização poderá resultar
numa reação química, com possibilidade de explosão.
Retire, elimine ou desligue todas as fontes de ignição; coloque fita
adesiva na tomada da parede. Não fume na área de pulverização.
Nunca abasteça o depósito de combustível com o motor em funciona-
mento ou quente.
Ponha em contato com a terra o pulverizador, o objeto a ser pulveriza-
do, e os baldes de tinta e de solventes.
Segure a pistola firmemente de encontro ao lado de um balde em contato
com a terra, quando estiver descarregando para dentro do mesmo.
Utilize somente tubos flexíveis condutores para pintura a alta pressão.
Nunca faça funcionar o motor numa área fechada.
A injeção de líquido é um ferimento grave! Se o líquido a alta pres-
são penetrar na sua pele, o ferimento poderá parecer “simplesmente
um corte”. Mas é um ferimento grave! Procure o médico imediatamente.
Para ajudar a evitar injeção de líquido, faça sempre o seguinte:
Engate o trinco de segurança do gatilho quando não estiver pulveri-
zando.
Sempre aponte a pistola para longe de você mesmo(a) ou de outras
pessoas.
Alivie a pressão antes de verificar ou reparar qualquer vazamento.
Alivie a pressão quando desligar o pulverizador ou parar de pulverizar.
Não utilize componentes classificados para uma pressão nominal
inferior à pressão máxima de trabalho dos sistemas.
Nunca permita que crianças utilizem esta unidade. Se sofrer algum
ferimento durante a utilização deste equipamento, procure o médico
imediatamente.

3309712
Component Identification and Function
TI0051
K
E
H
B
A
D
J
G
F
V
8050A
Fig. 1
U
N
M
PR T S
AMotor DC motor, permanent magnet, fan cooled
BDrive Assembly Transfers power from DC motor to displacement pump
DDisplacement Pump Transfers fluid to be sprayed from source through spray gun
EFluid Outlet Spray gun is connected here
FPrime Valve Used to prime and drain sprayer (also relieves fluid outlet pressure) when
open
GFluid Filter (optional) Final filter of fluid to spray gun
HPressure Adjusting Knob Controls fluid outlet pressure
JPressure Control Controls motor speed to maintain fluid outlet pressure at displacement pump
outlet. Works with pressure adjusting knob.
KON/OFF Switch Power switch that controls main power to sprayer
M50 ft (15 m) Main Hose 1/4 in. ID, grounded, nylon hose with spring guards on both ends
NSpray Gun High pressure spray gun with gun safety latch
PRAC IV Switch Tip Uses high pressure fluid to clear tip clogs without removing tip from spray gun
RTip Guard Tip guard reduces risk of injection injury
SGun Safety Latch Gun safety latch inhibits accidental triggering of spray gun
TPower Cord Rack Holds wrapped power cord for storage
USuction Hose Transfers fluid to be sprayed from source to pump
VDrain Tube Fluid outlet used to drain and prime the sprayer

4309712
General Repair Information
Pressure Relief Procedure
WARNING
INJECTION HAZARD
System pressure must be manually
relieved to prevent system from starting
or spraying accidentally. Fluid under high
pressure can be injected through skin and cause
serious injury. To reduce risk of injury from injec-
tion, splashing fluid, or moving parts, follow Pres-
sure Relief Procedure whenever you:
are instructed to relieve pressure,
stop spraying,
check or service any system equipment,
or install or clean spray tip.
1. Lock gun safety latch.
2. Turn ON/OFF switch to OFF.
3. Unplug power supply cord.
4. Unlock gun safety latch. Hold metal part of gun
firmly to grounded metal pail. Trigger gun to relieve
pressure.
5. Lock gun safety latch.
6. Open pressure drain valve. Leave pressure drain
valve open until ready to spray again.
If suspected that spray tip or hose is completely
clogged, or that pressure has not been fully relieved
after following steps above, VERY SLOWLY loosen tip
guard retaining nut or hose end coupling to relieve
pressure gradually, then loosen completely. Now clear
tip or hose obstruction.
CAUTION
To reduce risk of pressure control malfunction:
Use needle nose pliers to disconnect wire. Never
pull on wire, pull on connector.
Mate wire connectors properly. Center flat blade of
insulated male connector in female connector.
Route wires carefully to avoid interference with
other connections of pressure control. Do not pinch
wires between cover and control box.
1. Keep all screws, nuts, washers, gaskets, and
electrical fittings removed during repair proce-
dures. These parts are not normally provided with
replacement assemblies.
WARNING
ELECTRIC SHOCK HAZARD
MOVING PARTS HAZARD
To reduce risk of serious injury, including
electric shock, do not touch moving or
electrical parts with fingers or tools while
testing repair. Shut off and unplug spray-
er when inspection is complete. Install all
covers, gaskets, screws and washers
before operating sprayer.
2. Test repair after problem is corrected.
3. If sprayer does not operate properly, review
repair procedure to verify procedure was done
correctly. If necessary, see Troubleshooting Guide,
pages 5 – 9, for other possible solutions.
WARNING
HOT SURFACES HAZARD
EXPLOSION HAZARD
Motor and drive housing may be very hot
during operation and could burn skin if
touched.
Flammable materials spilled on hot, bare
motor could cause fire or explosion.
Have motor shroud in place during
operation to reduce risk of burns, fire or
explosion.
CAUTION
Do not run sprayer dry for more than 30 seconds to
avoid damaging pump packings.
4. Install motor shroud before operation of spray-
er and replace if damaged. Motor shroud prevents
overheating, and protects operator from possible
electrical shock by touching terminals of capacitor.
It can also reduce risk of burns, fire or explosion;
see preceding WARNING.

5309712
Grounding
WARNING
Improper installation or alteration of grounding plug
results in risk of electric shock, fire or explosion
that could cause serious injury or death.
1. Fig. 2. Both models require a 50/60 Hz, 15A circuit
with a grounding receptacle.
2. Do not alter ground prong or use adapter.
3. A 12 AWG, 3 wires with grounding prong, 300 ft
(90 m) extension cord may be used. Fi
g
. 2
Grounding Plug
Grounded
Outlets
Troubleshooting
Relieve pressure;page 4.
MOTOR WON’T OPERATE
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
Basic Fluid Pressure
Problems
1. Pressure control knob setting. Motor will not run
if at minimum setting (fully counterclockwise).
1. Slowly increase pressure setting to see if mo-
tor starts.
2. Spray tip or fluid filter may be clogged. 2. Relieve pressure and clear clog or clean fil-
ter; refer to separate gun or tip instruction
manual.
Basic Mechanical
Problems
1. Pump (13) for frozen or hardened paint. 1. Thaw sprayer if water or water-based paint
has frozen in sprayer. Place sprayer in warm
area to thaw. Do not start sprayer until
thawed completely. If paint hardened (dried)
in sprayer, replace pump packings. See
page 19 (Displacement Pump Replace-
ment).
2. Displacement pump connecting rod pin (9a).
Pin must be completely pushed into connecting
rod (9) and retaining spring (9b) must be firmly
in groove of pump pin. See Fig. 10.
2. Push pin into place and secure with spring re-
tainer.
3. Motor (1). Remove drive housing assembly
(10). See page 17. Try to rotate fan by hand.
3. Replace motor (1) if fan won’t turn. See page
18.
Basic Electrical Problems 1. Motor control board. Board shuts down and dis-
plays error code.
1. See Motor Control Board Diagnostics,
page 14.
2. Electrical supply:
Meter must read 85–130 Vac
2. Reset building circuit breaker; replace build-
ing fuse. Try another outlet.
3. Extension cord. Check extension cord continu-
ity with volt meter.
3. Replace extension cord.
4. Sprayer power supply cord (79). Inspect for
damage such as broken insulation or wires.
4. Replace power supply cord.

6309712
Troubleshooting
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
Basic Electrical Problems
(continued)
5. That motor leads are securely fastened and
properly mated.
5. Replace loose terminals; crimp to leads. Be
sure terminals are firmly connected.
Clean circuit board terminals. Securely re-
connect leads.
6. For loose motor brush lead connections and ter-
minals. See page 10.
6. Tighten terminal screws. Replace brushes if
leads are damaged. See page 10.
7. Brush length which must be 1/2 in. minimum.
See page 10.
NOTE:Brushes do not wear at the same rate on
both sides of motor. Check both brushes.
7. Replace brushes. See page 10.
8. For broken or misaligned motor brush springs.
Rolled portion of spring must rest squarely on
top of brush. See page 10.
8. Replace spring if broken. Realign spring with
brush. See page 10.
9. Motor brushes may be binding in brush holders.
See page 10.
9. Clean brush holders. Remove carbon with
small cleaning brush. Align brush leads with
slot in brush holder to assure free vertical
brush movement.
10.Motor armature commutator for burn spots,
gouges and extreme roughness.
See page 10.
10.Remove motor and have motor shop resur-
face commutator if possible. See page 18.
11. Motor armature for shorts using armature tester
(growler) or perform spin test. See page 10.
11. Replace motor. See page 18.
Refer to wiring diagram on
page 13, to identify test
points (TP).
1. Power supply cord (79). Connect volt meter be-
tween N (neutral) and TP1.
Plug in sprayer. Meter must read: 85–130 Vac.
Unplug sprayer.
1. Replace power supply cord.
2. ON/OFF switch (23). Connect volt meter be-
tween L and N terminal on ON/OFF switch. Plug
in sprayer and turn ON.
Meter must read 85–130 Vac
2. Replace ON/OFF switch. See page 12.
3. Motor thermal cutoff switch. Turn sprayer OFF.
Check for continuity between TO1 and TO2 with
ohmmeter.
3. If thermal switch is open (no continuity), allow
motor to cool. If switch remains open after
motor cools, replace motor. If thermal switch
closes after motor cools, correct cause of
overheating.
4. All terminals for damage or loose fit. 4. Replace damaged terminals and reconnect
securely.

7309712
Troubleshooting
LOW OR FLUCTUATING OUTPUT
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
Low Output 1. For worn spray tip. 1. Follow Pressure Relief Procedure Warn-
ing, then replace tip. See your separate
gun or tip manual.
2. Verify pump does not continue to stroke when
gun trigger is released.
2. Service pump. See page 19.
3. Filter clogged (If optional filter is installed). 3. Relieve pressure. Check and clean filter.
4. Prime valve leaking. 4. Relieve pressure. Repair prime valve.
5. Suction hose connections. 5. Tighten any loose connections.
6. Electrical supply with volt meter.
Meter must read 85–130 Vac.
Low voltages reduce sprayer performance.
6. Reset building circuit breaker; replace
building fuse. Repair electrical outlet or try
another outlet.
7. Extension cord size and length; must be at least
12 gauge wire and no longer than 300 ft. Longer
cord lengths reduce sprayer performance.
7. Replace with a correct, grounded exten-
sion cord.
8. Leads from motor to pressure control circuit
board (35) for damaged or loose wires or con-
nectors. Inspect wiring insulation and terminals
for signs of overheating.
8. Be sure male terminal blades are centered
and firmly connected to female terminals.
Replace any loose terminal or damaged
wiring. Securely reconnect terminals.
9. For loose motor brush leads and terminals. See
page 10.
9. Tighten terminal screws. Replace brushes
if leads are damaged. See page 10.
10.For worn motor brushes which must be 1/2 in.
minimum. See page 10.
10. Replace brushes. See page 10.
11. For broken and misaligned motor brush
springs. Rolled portion of spring must rest
squarely on top of brush.
11. Replace spring if broken. Realign spring
with brush. See page 10.
12.Motor brushes for binding in brush holders. See
page 10.
12.Clean brush holders, remove carbon dust
with small cleaning brush. Align brush lead
with slot in brush holder to assure free verti-
cal brush movement.
13.Low stall pressure. 13. Do either or both:
a. Turn pressure control knob fully
clockwise. Make sure pressure
control knob is properly installed
to allow full clockwise position.
b. Try a new transducer.
14.Motor armature for shorts by using an armature
tester (growler) or perform spin test. See page
10.
14.Replace motor. See page 18.

8309712
Troubleshooting
LOW OR FLUCTUATING OUTPUT
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
Motor runs and pump strokes 1. Paint supply. 1. Refill and reprime pump.
2. Intake strainer clogged. 2. Remove and clean, then reinstall.
3. Suction tube or fittings loose. 3. Tighten; use thread sealant or sealing tape
on threads if necessary.
4. To see if intake valve ball and piston ball are
seating properly. See page 19.
4. Remove intake valve and clean. Check
balls and seats for nicks; replace if neces-
sary, page 19. Strain paint before using to
remove particles that could clog pump.
5. Leaking around throat packing nut which may
indicate worn or damaged packings. See
page 19.
5. Replace packings, page 19. Also check
piston valve seat for hardened paint or
nicks and replace if necessary. Tighten
packing nut/wet-cup.
6. Pump rod damage. 6. Repair pump, page 19.
7. Capacitor failure. Visually inspect capacitor
near terminals. Ensure that orange safety re-
lief plug is intact.
7. Replace capacitor.
Motor runs but pump does not
stroke
1. Displacement pump pin (9a) (damaged or
missing), page 19.
1. Replace pump pin if missing. Be sure re-
tainer spring (9b) is fully in groove all
around connecting rod, page 19.
2. Connecting rod assembly (9) for damage,
page 17.
2. Replace connecting rod assembly,
page 17.
3. Gears or drive housing, page 17. 3. Inspect drive housing assembly and gears
for damage and replace if necessary,
page 17.

9309712
Troubleshooting
MOTOR IS HOT AND RUNS INTERMITTENTLY
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
Motor is hot and runs intermit-
tently.
1. Determine if sprayer was operated at high
pressure with small tips, which causes low
motor RPM and excessive heat build up.
1. Decrease pressure setting or increase tip
size.
2. Be sure ambient temperature where sprayer
is located is no more than 90F and sprayer
is not located in direct sun.
2. Move sprayer to shaded, cooler area if pos-
sible.
ELECTRICAL SHORT
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
Building circuit breaker opens
as soon as sprayer switch is
turned on.
1. All electrical wiring for damaged insulation, and
all terminals for loose fit or damage. Also wires
between pressure control and motor. See page
18.
1. Repair or replace any damaged wiring or
terminals. Securely reconnect all wires.
2. For missing inspection plate gasket (see page
18), bent terminal forks or other metal to metal
contact points which could cause a short.
2. Correct faulty conditions.
3. Motor armature for shorts. Use an armature
tester (growler) or perform spin test. See page
10. Inspect windings for burns.
3. Replace motor. See page 18.
4. Motor control board (35) by performing motor
control board diagnostics on page 14. If diag-
nostics indicate, substitute with a good board.
CAUTION: Do not perform this check until mo-
tor armature is determined to be good. A bad
motor armature can burn out a good board.
4. Replace with a new pressure control board
(35). See page 14.
1. Basic Electrical Problems on page 5. 1. Perform necessary procedures.
2. ON/OFF switch (23) See page 12. Be sure
sprayer is unplugged! Disconnect wires from
switch. Check switch with ohmmeter. Reading
must be infinity with ON/OFF switch OFF, and
zero with switch ON.
2. Replace ON/OFF switch. See page 12.
3. For damaged or pinched wires in pressure con-
trol. See page 14.
3. Replace damaged parts. See page 14.
Sprayer quits after sprayer op-
erates for 5 to 10 minutes.
1. Basic Electrical Problems on page 5. 1. Perform necessary procedures.
2. Electrical supply with volt meter.
Meter must read 85–130 Vac.
2. If voltage is too high, do not operate
sprayer until corrected.
3. Tightness of pump packing nut. Over tightening
tightens packings on rod, restricts pump action,
and damages packings.
3. Loosen packing nut. Check for leaking
around throat. Replace pump packings, if
necessary. See page 19.
.
CAUTION
Any short in any part of the
motor power circuit will cause
the control circuit to inhibit
sprayer operation. Correctly
diagnose and repair all shorts
before checking and replac-
ing control board.
Building circuit breaker opens
as soon as sprayer is plugged
into outlet and sprayer is NOT
turned on.

10 309712
Spin Test
Setup
Electric Shock Hazard; page 4.
To check armature, motor winding and brush electrical
continuity:
1. Relieve pressure;page 4.
2. Remove drive housing; page 17.
3. Fig. 3. Remove pressure control cover (39). Dis-
connect motor leads (F) and (G).
4. Fig. 4. Remove motor shroud (74).
Armature Short Circuit Test
Quickly turn motor fan by hand. If no electrical shorts,
motor coasts two or three revolutions before complete
stop. If motor does not spin freely, armature is shorted.
Replace motor; page 18.
Armature, Brushes, and Motor Wiring Open
Circuit Test (Continuity)
1. Connect red and black motor leads together with
test lead. Turn motor fan by hand at about two
revolutions per second.
2. If uneven or no resistance, check for: broken brush
springs, brush leads, motor leads; loose brush
terminal screws, motor lead terminals; worn
brushes. Repair as needed; page 10.
3. If still uneven or no resistance, replace motor;
page 18.
9578A
Fig. 3
F
G
39
Motor Brush Replacement
Motor Brush Removal
Replace brushes worn to less than 1/2 in. Check both
sides. Brush Repair Kit 243215.
1. Read General Repair Information; page 4.
2. Relieve pressure;page 4.
3. Fig. 4. Remove four screws (18) and motor
shroud (74).
4. Pry off two brush caps (A). Tag locations of red (+)
and black (–) motor leads.
5. Fig. 5. Remove brush lead from control box and
discard brush (B).
(Continued on page 11)
ti3348a
A
74
Fig. 4
18

11309712
Motor Brush Replacement
6. Fig. 5. Insert brush (B). Push clip (A) until it snaps
into place and secures brush.
CAUTION
When installing brushes, follow all steps carefully to
avoid damaging parts.
7. Fig. 5. Install red (+) and black (–) motor leads
according to tags. Install brush lead into control
box and connect to board.
ti3349a
Fig. 5
A
B
8. Inspect commutator for excessive pitting, burning
or gouging. A black color on commutator is normal.
Have commutator resurfaced by a motor repair
shop if brushes wear too fast.
9. Test brushes.
a. Remove pump (13); Displacement Pump
Replacement, page 19.
b. With sprayer OFF, turn pressure control knob
fully counterclockwise to minimum pressure.
Plug in sprayer.
c. Turn sprayer ON. Slowly increase pressure
until motor is at full speed.
10. Break in brushes.
a. Operate sprayer 1 hour with no load.
b. Install pump (13); Displacement Pump Re-
placement, page 19.

12 309712
On/Off Switch Replacement
120 Vac; 234139, 234140
Removal
1. Relieve pressure;page 4.
2. Fig. 6 and 7. Remove four screws (18) and pres-
sure control cover (39).
3. Disconnect two wires (A) from ON/OFF
switch (23).
4. Remove toggle boot (25). Remove ON/OFF
switch (23).
Installation
1. Install new ON/OFF switch (23). Install toggle
boot (25).
2. Connect two wires (A) to ON/OFF switch.
3. Install pressure control cover (39) with four
screws (18).
ti3350a
Fig. 6
39
A
18
23
52
E
D
35
36
25 37
22

13309712
On/Off Switch Replacement
120 Vac
Fig. 7
Wiring Diagram
234139, A
234140, A
Pressure
Transducer
ON/OFF
Switch
Power
Plug
Potentiometer
from Motor
Capacitor
Black
Green
White
Yellow
Black (–)
Red (+)
N
L
M+ M– TO1 TO2
J7
J8
ti2159a
TP1

14 309712
Pressure Control Repair
Motor Control Board Diagnostics
Note: Keep a new transducer on hand to use for test.
CAUTION
Do not allow sprayer to develop fluid pressure with-
out transducer installed. Leave drain valve open if
test transducer is used.
1. Remove four screws (18) and cover (39).
2. Turn ON/OFF switch ON.
3. Observe LED operation and reference following
table:
4. Relieve pressure and un-
plug sprayer before servic-
ing control board;page 4.
LED
BLINKS SPRAYER OPERATION INDICATES WHAT TO DO
Once Sprayer runs Normal operation Do nothing
Once and
stays ON
Sprayer shuts down and LED stays ON Motor open circuit or bad
control board
Check motor brushes and
armature. If OK, replace mo-
tor control board.
Two times
repeatedly
Sprayer shuts down and LED continues
to blink two times repeatedly
Run away pressure. Pres-
sure greater than 4500 psi
(310 bar, 31 MPa).
Replace motor control board.
See following Motor Control
Board procedure.
Three times
repeatedly
Sprayer shuts down and LED continues
to blink three times repeatedly
Pressure transducer is
faulty or missing
Check transducer connection.
Open drain valve. Substitute
new transducer for transducer
in sprayer. If sprayer runs,
replace transducer.
Four times
repeatedly
Sprayer shuts down and LED continues
to blink four times repeatedly
Line voltage is too high Check for voltage supply
problems
Five times
repeatedly
Sprayer shuts down and LED continues
to blink five times repeatedly
Too much current Check for locked rotor,
shorted wiring or motor. Re-
pair or replace failed parts.
Six times
repeatedly
Sprayer shuts down and LED continues
to blink six times repeatedly
Motor thermal switch
open circuit
Check for binding in pump or
drive. Check for bad motor.

15309712
Pressure Control Repair
Motor Control Board
Removal
Refer to Fig. 6 and 7.
1. Relieve pressure;page 4.
2. Remove four screws (18) and cover (39).
3. Disconnect at motor control board (35):
Four motor leads: two yellow, black (–)
and red (+).
Two line voltage leads.
Lead (D) from potentiometer.
Lead (E) from transducer.
4. Remove five screws (36) and circuit board (35).
Installation
1. Clean pad on rear of motor control board. Apply
small amount of thermal compound 073019 to pad.
2. Fig. 6. Install motor control board (35) with five
screws (36).
3. Connect to motor control board (35):
Lead (E) to transducer.
Lead (D) to potentiometer.
Two line voltage leads.
Four motor leads: two yellow, black (–)
and red (+).
4. Install cover (39) with four screws (18).

16 309712
Pressure Control Repair
Pressure Control Transducer
Removal
Refer to Fig. 6 and 7.
1. Relieve pressure;page 4.
2. Remove four screws (18) and cover (39).
3. Disconnect lead (E) from motor control
board (35).
4. Remove two screws (22) and filter housing (45).
5. Thread transducer lead plastic connector down
through transducer grommet (28).
6. Remove pressure control transducer (52) and
packing o-ring (51) from filter housing.
Installation
1. Install packing o-ring (51) and pressure control
transducer (52) in filter housing (45). Torque to
30–35 ft-lb.
2. Thread transducer lead plastic connector up
through transducer grommet (28).
3. Install filter housing (45) with two screws (22).
4. Connect lead (E) to motor control board (35).
5. Install cover (39) with four screws (18).
Pressure Adjust Potentiometer
Removal
Refer to Fig. 6 and 7.
1. Relieve pressure;page 4.
2. Remove four screws (18) and cover (39).
3. Disconnect all leads from motor control board (35).
4. Remove five screws (36) and board (35)
5. Remove potentiometer knob (27), sealing shaft nut
(33) and pressure adjust potentiometer (26).
Installation
1. Install pressure adjust potentiometer (26), sealing
shaft nut (33) and potentiometer knob (27).
a. Turn potentiometer fully clockwise.
b. Install knob at full clockwise position.
2. Install board (35) with five screws (36).
3. Connect all leads to motor control board (35).
4. Install cover (39) with four screws (18).

17309712
Drive Housing Replacement
CAUTION
Do not drop gear cluster (7) when removing drive
housing (10). Gear cluster may stay engaged in
motor front end bell or drive housing.
Disassembly
1. Relieve pressure;page 4.
2. Remove pump (13); Displacement Pump Re-
placement, page 19.
3. Fig. 8. Remove two screws (18a).Tip sprayer up.
Remove two screws (18b) and remove shroud
(74).
4. Remove two front screws (22).
5. Remove two back screws (22).
6. Pull drive housing (10) off of motor (1).
Assembly
1. Push drive housing (10) onto motor (1)
2. Install two front screws (22).
3. Install two back screws (22).
4. Fig. 8. Install shroud (74) with two screw (18a).Tip
sprayer up. Install two screws (18b).
5. Install pump (13); Displacement Pump Replace-
ment, page 19.
6. Install new access cover (10a) with two screws
(10b).
ti3352a
ti0052b
10
22
1
Fig. 8
18b
74
18b
7
10a
10b
18a
22

18 309712
Motor Replacement
Disassembly
1. Relieve pressure;page 4.
2. Remove pump (13); Displacement Pump Re-
placement, page 19.
CAUTION
Do not drop gear cluster (7) when removing drive
housing (10). Gear cluster may stay engaged in
motor front end bell or drive housing.
3. Remove drive housing (10); Drive Housing Re-
placement, page 17.
4. Remove four screws (18) and cover (39).
5. Disconnect all leads from board (35). Remove five
screws (36) and board.
6. Remove strain relief (37; Fig. 6) and motor fan (2).
7. Remove three screws (22) behind board and
remove control housing (21).
8. Remove four screws (22) and motor (1) from
frame (63).
Assembly
1. Install new motor (1) on frame (63) with four
screws (22).
2. Install control housing (21) with three screws (22).
3. Install strain relief (37; Fig. 6) and motor
fan (2).
4. Install board (35) with five screws (36). Connect all
leads to board (35).
5. Install drive housing (10); Drive Housing Re-
placement, page 17.
6. Install pump (13); Displacement Pump Replace-
ment, page 19.
ti3351a
Fig. 9
22
1
1Liberally apply grease
39
1
18
36
35
22 1
63

19309712
Displacement Pump Replacement
Removal
1. Flush pump (13).
2. Relieve pressure;page 4.
3. Fig. 10. Loosen two screws (10b) and rotate
cover (10a).
i
g. 10
10a
b
9a
9573A
4. Cycle pump until pump pin (9a) is in position to be
removed. Remove pump pin (9a).
5. Fig. 11. Remove suction tube (78) and hose (19).
6. Loosen pump jam nut (12). Unscrew pump.
T
Fig. 11
78
12
19
TI0062
Installation
WARNING
If pin works loose, parts could break off due to
force of pumping action. Parts could project
through the air and result in serious injury or prop-
erty damage.
CAUTION
If the pump locknut loosens during operation, the
threads of the drive housing will be damaged.
1. Fig. 12. Extend pump piston rod fully. Apply grease
to top of pump rod at (A) or inside connecting rod.
Fig. 12
A
TI0062
2. Fig. 10. Install pump pin (9a). Verify retainer spring
(9b) is in groove of pump pin.
3. Push pump up until pump threads engage.
4. Screw in pump until threads are flush with drive
housing opening. Align pump outlet to back.
5. Fig. 11. Install suction tube (78) and hose (19).
6. Fig. 13. Screw jam nut (12) up onto pump until nut
stops. Tighten jam nut by hand, then tap 1/8 to 1/4
turn with a 20 oz (maximum) hammer to approxi-
mately 75 +/–5 ft-lb (102 Nm).
Fig. 13 TI0063
7. Fig. 14. Fill packing nut with Graco TSL until fluid
flows onto top of seal.
TI0061
Fig. 14
10a
10b
8. Fig. 10. rotate cover (10a); tighten screws (10b).

20 309712
Technical Data
100–120V, ∅, A,
Hz
Generator
Minimum W
Motor HP (W) Cycles per gallon (li-
ter)
Maximum
Delivery gpm
(lpm)
Maximum
Tip size
Fluid Outlet
npsm
1, 15, 50/60 3000 7/8 (653) 680 (180) 0.38 (1.44) 0.019 1/4 in.
Basic Sprayer Wetted Parts: . . . . . . . . . . . . . . . . . . . . . . . . . . .
zinc-plated carbon steel, polyurethane, polyethylene,
stainless steel, PTFE,Delrin,chrome plating,
leather, UHMWPE, aluminum, tungsten carbide
NOTE: Delrin is a registered trademark of the
DuPont Co.
Noise Level
Sound Power 87 dB(A)*. . . . . . . . . . . . . . . . . . . . . . . . . .
Sound Pressure 75 dB(A)*. . . . . . . . . . . . . . . . . . . . . . .
* ISO 3744; measured at 3.1 feet (1 m)
Dimensions
Weight lb (kg) Height in. (cm) Length in. (cm) Width in. (cm)
34.5 (15.7) 17.75 (45.1) 14.5 (36.8) 13.5 (34.3)
Graco Phone Number
TO PLACE AN ORDER OR FOR SERVICE, contact your Graco distributor,
or call 1–800–690–2894 to identify the nearest distributor.
All written and visual data contained in this document reflects the latest product information available at the time of publication.
Graco reserves the right to make changes at any time without notice.
Sales Offices: Minneapolis, Detroit
International Offices: Belgium, Korea, Hong Kong, Japan
www.graco.com
PRINTED IN USA 309712 2/2003