Graco T-Max 405 A Series Operating instructions

ti4100a
Repair
GRACO INC. P.O. BOX 1441 MINNEAPOLIS, MN 55440–1441
Copyright 2004, Graco Inc. is registered to I.S. EN ISO 9001
T-Max 405t
Texture Sprayer
– For Water-Based Materials Only –
40 Bar (4 MPa, 580 psi) Maximum Working Pressure
Model 248195, Series A
Model 248269, Series A
Model 249075, Series A
309977 rev. F
Read warnings and instructions.
309978. . . . . . .
309973. . . . . . .

2 309977
Table of Contents
Warnings 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Repair Information 4. . . . . . . . . . . . . . . . . . . . . .
Pressure Relief 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spin Test 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Motor Brush Replacement 11. . . . . . . . . . . . . . . . . . . . . .
Motor Replacement 13. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pressure Control Repair 15. . . . . . . . . . . . . . . . . . . . . . . .
Motor Control Board Diagnostics 15. . . . . . . . . . . . . . .
Motor Control Board 16. . . . . . . . . . . . . . . . . . . . . . . . . .
Pressure Control Transducer 17. . . . . . . . . . . . . . . . . .
Pressure Adjust Potentiometer 17. . . . . . . . . . . . . . . . .
Pump Repair 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bearing Housing & Connecting Rod 21. . . . . . . . . . . . . .
Drive Housing 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Drawing 24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts List 25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wiring Diagram 27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Technical Data 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Graco Warranty 32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Graco Phone Number 32. . . . . . . . . . . . . . . . . . . . . . . . . .

3309977
WARNING
FIRE AND EXPLOSION HAZARD
Flammable fumes, such as solvent, in work area can ignite or explode. To help prevent fire and explosion:
DKeep work area free of debris, including solvent, rags and gasoline.
DGround equipment in the work area. See Grounding instructions.
DIf there is static sparking or you feel a shock, stop spraying immediately. Do not use equipment until you
identify and correct the problem. Keep sprayer at least 20 ft (6m) away from explosive vapors.
INSTRUCTIONS
EQUIPMENT MISUSE HAZARD
Misuse can cause death or serious injury.
DDo not exceed the maximum working pressure or temperature rating of the lowest rated system component.
See Technical Data in all equipment manuals.
DUse water–based materials. Use fluids and solvents that are compatible with equipment wetted parts. See Technical
Data in all equipment manuals. Read fluid and solvent manufacturer’s warnings. Do no use with quick-set materials.
DCheck equipment daily. Repair or replace worn or damaged parts immediately.
DDo not alter or modify equipment.
DUse equipment only for its intended purpose. Call your Graco distributor for information
DRoute hoses and cables away from traffic areas, sharp edges, moving parts, and hot surfaces.
DDo not use hoses to pull equipment.
DKeep children and animals away from work area.
DComply with all applicable safety regulations.
PRESSURIZED EQUIPMENT HAZARD
Fluid from the applicator, leaks, or ruptured components can splash in the eyes or on skin and cause serious
injury.
DFollow Pressure Relief Procedure in this manual, when you stop spraying and before cleaning, checking, or
servicing equipment.
DTighten all fluid connections before operating the equipment.
DCheck hoses, tubes, and couplings daily. Replace worn or damaged parts immediately.
PERSONAL PROTECTIVE EQUIPMENT
You must wear appropriate protective equipment when operating, servicing, or when in the operating area of the
equipment to help protect you from serious injury, including eye injury, inhalation of toxic fumes, burns, and hearing
loss. This equipment includes but is not limited to:
DProtective eyewear
DClothing and respirator as recommended by the fluid and solvent manufacturer
DGloves
DHearing protection
ELECTRIC SHOCK HAZARD
Improper grounding, setup, or usage of the system can cause electric shock.
DTurn off and disconnect power cord before servicing equipment.
DUse only grounded electrical outlets.
DUse only 3–wire extension cords.
DEnsure ground prongs are intact on sprayer and extension cords.
DDischarge any residual capacitor voltage with a resistive load across terminals.
MOVING PARTS HAZARD
Moving parts can pinch or amputate fingers and other body parts.
DKeep clear of moving parts.
DDo not operate equipment with protective guards or covers removed.
DPressurized equipment can start without warning. Before checking, moving, or servicing equipment, follow the
Pressure Relief Procedure in this manual. Disconnect power or air supply.

4 309977
General Repair Information
Pressure Relief
WARNING
PRESSURIZED EQUIPMENT HAZARD
The system pressure must be manually relieved to
prevent the system from starting or spraying
accidentally. To reduce the risk of an injury from
accidental spray from the applicator, splashing
fluid, or moving parts, follow the Pressure Relief
Procedure whenever you
DAre instructed to relieve the pressure
DStop spraying
DCheck or service any of the system equipment
DInstall or clean the spray nozzle
Pressure Relief Procedure
1. Turn pump control off (0).
2. Point applicator into hopper. Turn applicator on.
3. Open the applicator air valve (handle parallel with
valve body).
4. Unplug the electrical power cord.
5. Hold hose firmly in one hand and slowly open one
cam arm at a time. Remove hose from pump
outlet.
Grounding and Electrical Requirements
WARNING
Improper installation or alteration of the grounding
plug will result in a risk of electric shock, fire or
explosion that could cause serious injury or death.
Voltage Requirements
DFig. 1. 220–240 Vac models require a 50 Hz, 16A
circuit with a grounding receptacle. 100–120 Vac
models require a 50/60 Hz, 16A circuit with a
grounding receptacle.
Fig. 1
grounded
outlet
ti4109b
grounding prong
240 Vac model shown
DDo not alter the ground prong or use an
ungrounded adapter.
Extension Cords
DUse only an extension cord with an undamaged,
3-prong plug.
D120 Vac: A 12 AWG, 3 wires with grounding prong,
300 ft (90 m) extension cord may be used.
220–240 Vac: You may use a 3-wire, 1.0 mm (12
AWG) (minimum) extension cord up to 90 m long.
Long lengths reduce sprayer performance..

5309977
General Repair Information
Auxiliary Air Compressor
An external air compressor may be connected to the
applicator air line fitting. This may be useful for the
application of decorative or hard-to-spray materials.
WARNING
Overpressurizing the system may cause compo-
nent rupture and result in serious injury. To reduce
risk of overpressurizing system:
DDo not use a compressor with an output pressure
greater than 250 psi (1.7 MPa, 17 bar).
DAttach Graco 25 mm x 5m hose to pump outlet.
Hose Size and Lengths
The system comes with the following hoses:
Hose
Type
Inside Diameter (ID)
mm (in.)
Length
m (ft)
Fluid 25 mm (1.0) 5 (16)
Fluid 19 mm (.75) 3 (10)
Air 9.5 mm (.375) 15 (49)
Hose Usage
Always attach the 25 mm x 5m hose to the pump
outlet. Other hoses may then be added up to the
maximum fluid hose lengths:
DUse shortest fluid hose length required for the
spray application [(25 mm x 5m) minimum; see
Warning].
DUnnecessary hose length decreases sprayer
performance.
DMaximum fluid hose lengths:
15 m of 25 mm ID
– or –
10 m of 25 mm ID combined with 3 m of 19 mm ID
fluid hose.
WARNING
The motor has a thermal overload switch that shuts
down the motor if it overheats.
To reduce the risk of serious bodily injury due to the
system restarting unexpectedly, always turn the
pressure control to OFF (0).
WARNING
Quick-set materials can harden, plug passage
ways and cause the sprayer to become over
pressurized. An over-pressurized system can
cause components to burst and cause bodily injury.
To reduce the risk of bodily injury due to over
pressurization of the system, do not use quick-set
materials.

6 309977
Troubleshooting
See Pressure Relief Procedure on 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 (31) 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 packing.
See page 18 (Pump Repair).
2. Displacement pump connecting rod pin (75).
Pin must be completely pushed into connecting
rod (45) and retaining spring (76) must be firmly
in groove of pump pin. See Fig. 9.
2. Push pin into place and secure with spring re-
tainer.
3. Motor (33). Remove drive housing assembly
(37). See page 13. Try to rotate fan by hand.
3. Replace motor (33) if fan won’t turn. See
page 13.
Basic Electrical Problems 1. Motor control board. Board shuts down and dis-
plays error code.
1. See Motor Control Board Diagnostics,
page 15.
2. Electrical supply. Meter must read:
210–255 Vac for 220–240 Vac models;
85–130 Vac for 100–120 Vac models.
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. Inspect for damage
such as broken insulation or wires.
4. Replace power supply cord.

7309977
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 11.
6. Tighten terminal screws. Replace brushes if
leads are damaged. See page 11.
7. Brush length which must be 1/4 in. minimum.
See page 11.
NOTE: Brushes do not wear at the same rate on
both sides of motor. Check both brushes.
7. Replace brushes. See page 11.
8. For broken or misaligned motor brush springs.
Spring must rest squarely on top of brush. See
page 11.
8. Replace brush if spring is broken.
See page 11.
9. Motor brushes may be binding in brush holders.
See page 11.
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 11.
10.Remove motor and have motor shop resur-
face commutator if possible. See page 13.
11. Motor armature for shorts using armature tester
(growler) or perform spin test. See page 11.
11. Replace motor. See page 13.
Refer to wiring diagram on
page 27 to identify test
points (TP).
1. Power supply cord. Connect volt meter be-
tween TP1 (L1, 240 Vac) and TP2 (L2, Neutral).
Plug in sprayer. Meter must read:
210–255 Vac for 220–240 Vac models;
85–130 Vac for 100–120 Vac models.
Unplug sprayer.
1. Replace power supply cord.
2. Motor thermal cutoff switch. Turn sprayer OFF.
Check for continuity between TO1 and TO2 with
ohmmeter.
2. 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.
3. All terminals for damage or loose fit. 3. Replace damaged terminals and reconnect
securely.

8 309977
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. Check piston and intake
valves for wear or obstructions.
See page 18.
3. Filter clogged (If optional filter is installed). 3. Relieve pressure. Check and clean filter.
4. Material hose length. Longer hose length re-
duces sprayer performance.
4. Replace with hose length less than speci-
fied maximum.
5. Pump hopper adapter connections. 5. Tighten any loose connections. Replace
pump hopper adapter if cracked or punc-
tured.
6. Electrical supply with volt meter.
Meter must read:
210–255 Vac for 220–240 Vac models;
85–130 Vac for 100–120 Vac models.
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
1.0 mm2(12 awg) wire and no longer than 90 m
(295 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 (38) 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 11.
9. Tighten terminal screws. Replace brushes
if leads are damaged. See page 11.
10.For worn motor brushes which must be 1/4 in.
minimum. See page 11.
10. Replace brushes. See page 11.
11. For broken and misaligned motor brush
springs. Spring must rest squarely on top of
brush.
11. Replace brush if spring is broken. See
page 11.
12.Motor brushes for binding in brush holders.
See page 11.
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 11.
14.Replace motor. See page 13.

9309977
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. Material supply. 1. Refill hopper and reprime pump.
2. Loose fittings. 2. Tighten; use thread sealant or sealing tape
on threads if necessary.
3. Intake valve ball and piston ball are seating
properly. See page 18.
3. Remove intake and piston valves and
clean. Check balls and seats for nicks or
obstructions; replace if necessary, page
18. Clean hopper before using to remove
particles that could clog pump.
4. Leaking around throat packing nut which may
indicate worn or damaged packings. See
page 18.
4. Replace packing, page 18. Also check pis-
ton valve seat for hardened paint or nicks
and replace if necessary. Tighten packing
nut.
5. Pump rod damage. 5. Repair pump, page 18.
6. Capacitor failure. Visually inspect capacitor
near terminals. Ensure that orange safety re-
lief plug is intact.
6. Replace capacitor.
Motor runs but pump does not
stroke
1. Displacement pump pin (75) (damaged or
missing), page 18.
1. Replace pump pin if missing. Be sure re-
tainer spring (76) is fully in groove all
around connecting rod, page 18.
2. Connecting rod assembly (45) for damage,
page 21.
2. Replace connecting rod assembly,
page 21.
3. Gears or drive housing, page 22. 3. Inspect drive housing assembly and gears
for damage and replace if necessary,
page 22.

10 309977
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
13.
1. Repair or replace any damaged wiring or
terminals. Securely reconnect all wires.
2. Bent terminal forks or other metal to metal con-
tact 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
11. Inspect windings for burns.
3. Replace motor. See page 13.
4. Motor control board (38) by performing motor
control board diagnostics on page 15. 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
(38). See page 15.
1. Basic Electrical Problems on page 6. 1. Perform necessary procedures.
2. For damaged or pinched wires in pressure
control. See page 15.
2. Replace damaged parts. See page 15.
Sprayer quits after sprayer op-
erates for 5 to 10 minutes.
1. Basic Electrical Problems on page 6. 1. Perform necessary procedures.
2. Electrical supply with volt meter.
Meter must read:
210–255 Vac for 220–240 Vac models;
85–130 Vac for 100–120 Vac models.
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 18.
.
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.

11309977
Spin Test
Setup
Electric Shock Hazard; page 3.
To check armature, motor winding and brush electrical
continuity:
1. Relieve pressure;page 4.
2. Remove motor, page 13.
3. Fig. 3. Remove six screws (12) and motor
cover (18).
4. Fig. 2. Disconnect wire harness (155) from control
board.
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 13.
Armature, Brushes, and Motor Wiring Open
Circuit Test (Continuity)
1. Connect wire harness (155) leads together with
test lead (A). 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 11.
3. If still uneven or no resistance, replace motor;
page 13.
Fig. 2 ti4816a
155
A
Motor Brush Replacement
Motor Brush Removal
Replace brushes worn to less than 1/2 in. Check both
sides. Order Brush Repair Kit 243642 for 220 – 240
Vac motors and 243215 for 100 – 120 Vac motors with
external capacitor.
1. Read General Repair Information; page 4.
2. Relieve pressure;page 4.
3. Fig. 6. Remove six screws (12) and motor
cover (18).
4. Electric Shock Hazard; page 3.
Fig. 3. Discharge any residual capacitor voltage
with a resistive load across terminal screws (41).
5. Fig. 4. Pry off two brush caps (A). Tag locations of
red (+) and black (–) motor leads.
6. Fig. 5. Remove screws (41) and discard brushes
(B) for motor with capacitor attached.
(Continued on page 12)
Fig. 3
41
ti4815a

12 309977
Motor Brush Replacement
CAUTION
When installing brushes, follow all steps carefully to
avoid damaging parts.
7. Fig. 4. Insert brush (B). Push clip (A) until it snaps
into place and secures brush.
8. Install red brush lead (+) and black brush lead (–)
according to markings on the motor and capacitor.
Install brush lead end to capacitor with screw (41).
A
B
ti4815a
+
–
+
Fig. 4
9. 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.
10. Test brushes.
a. Disconnect pump (31); Pump Repair,
Removal, steps 8 and 9, page 18.
b. With sprayer OFF, turn pump control knob fully
counterclockwise to minimum pressure. Plug
in sprayer.
c. Turn sprayer ON. Slowly increase pressure
until motor is at full speed.
11. Break in brushes.
a. Operate sprayer 1 hour with no load.
b. Connect pump (31); Pump Repair,
Installation, step 4, page 18.

13309977
Motor Replacement
Removal
1. Relieve pressure;page 4.
2. Fig. 5. Remove pump module (A).
a. Loosen clamp rod (20).
b. Release hopper quick-release clamp (28).
c. Disconnect pump module (A) from frame (35).
Fig. 5
20
ti5130a
A
28
35
3. Fig. 6. Remove six screws (12 ) and motor
cover (18).
4. Remove two screws (41) and disconnect leads
from capacitor (42) to control board (38).
5. Disconnect two yellow leads (B) from control
board (38).
6. Pull strain relief (49) out of bracket and thread
yellow leads connector through bracket.
7. Remove four screws (90) and washers (71) from
gear housing base (25), Parts Drawing, page 24.
8. Tip motor and drive housing assembly back and
remove two screws (86) and washers (84).
CAUTION
Do not drop gear cluster (D) when removing drive
housing (37). Gear cluster may stay engaged in
motor front end bell or drive housing.
9. Return motor and drive housing assembly to
vertical position.
10. Remove four screws (85) and washers (84).
Remove motor (33) from drive housing (37).
Installation
CAUTION
When installing motor, carefully align gears to avoid
damaging mating parts.
1. Fig. 6. Place new motor (33) on drive housing (37).
Rotate fan (C). When gears are felt to mesh, install
four washers (84) and screws (85).
2. Tip motor and drive housing assembly back and
install two washers (84) and screws (86).
3. Install motor and drive housing to gear housing
base (25) with four screws (90) and washers (71).
4. Thread yellow lead (B) through strain relief (49)
and connect to control board (38). Install strain
relief in bracket.
5. Connect red brush lead (+) and black brush lead
(–) according to markings on the motor and
capacitor. Install brush lead ends and wire harness
(155) lead ends to capacitor with screw (41). See
Wiring Diagram, page 27 to verify polarity is
correct.
6. Install motor cover (18) with five screws (12).

14 309977
Motor Replacement
90_
12
18
2 Yellow
42
85
33
37
86
84
8584
84
25
42 41
40
71
90
D
C
ti4811a
B
41
49
83
38
12
Fig. 6

15309977
Pressure Control Repair
Motor Control Board Diagnostics
Note: Keep a new transducer on hand to use for test.
1. Relieve pressure;page 4.
2. Remove five screws (12) and motor cover (18).
CAUTION
Do not allow sprayer to develop fluid pressure with-
out transducer installed.
3. Plug in power cord.
4. Observe LED operation and reference following
table:
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 57 bar
(5.7 MPa, 830 psi).
Replace pressure transducer
or 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.

16 309977
Pressure Control Repair
Motor Control Board
Removal
Refer to Wiring Diagram, page 27.
1. Relieve pressure;page 4.
2. Remove five screws (12) and motor cover (18).
3. Cut wire tie holding wiring to motor control
board (38).
4. Disconnect at motor control board (38):
DMotor wire harness: brown (+), blue (–).
DTwo line voltage leads: brown (+), blue (–).
DLead (D) from potentiometer.
DLead (E) from transducer.
DTwo leads (F) from motor thermal switch.
5. Remove six screws (83) and circuit board (38).
Installation
CAUTION
Electrostatic discharges can damage components on
motor control board. Use a ground strap when
handling or installing motor control board.
1. Fig. 7. Remove old thermal paste from control box.
Remove protective cover from thermal pad on new
motor control board.
Fig. 7 ti8397a
2. Fig. 6. Install motor control board (38) with six
screws (83).
3. Connect to motor control board (38):
DTwo leads (F) from motor thermal switch.
DLead (E) to transducer.
DLead (D) to potentiometer.
DTwo line voltage leads: brown (+), blue (–).
DMotor wire harness: brown (+), blue (–).
4. Bundle and tie all loose wires together.
5. Install motor cover (18) with five screws (12).

17309977
Pressure Control Repair
Pressure Control Transducer
Removal
Refer to Wiring Diagram, page 27.
1. Relieve pressure;page 4.
2. Remove five screws (12) and motor cover (18).
3. Disconnect lead (E) from motor control
board (38).
4. Remove strain relief (49) from circuit board bracket
(21). Thread transducer connector through
bracket.
5. Remove pressure control transducer (43) and
packing o-ring (89) from pump housing (202).
Installation
1. Install packing o-ring (89) and pressure control
transducer (43) in pump housing (202). Torque to
30–35 ft-lb.
2. Thread transducer connector through circuit board
bracket (21). Install strain relief (49) in circuit board
bracket.
3. Connect lead (E) to motor control board (38).
4. Install motor cover (18) with five screws (12).
Pressure Adjust Potentiometer
Removal
Refer to Wiring Diagram, page 27.
1. Relieve pressure;page 4.
2. Remove five screws (12) and motor cover (18).
3. Disconnect potentiometer lead (47) from motor
control board (38).
4. Remove potentiometer knob (16), gasket (88) and
pressure adjust potentiometer (47).
Installation
1. Install pressure adjust potentiometer (47), gasket
(88) and potentiometer knob (16).
a. Turn potentiometer fully clockwise.
b. Install knob at full clockwise position.
2. Connect potentiometer lead (47) to motor control
board (38).
3. Install motor cover (18) with five screws (12).

18 309977
Pump Repair
Removal
1. Relieve pressure;page 4.
2. Perform Storage More than 24 hours procedure
in Operation Manual 309973, 309974 or 309975.
3. Fig. 8. Loosen clamp rod (20).
20
Fig. 8
ti5130a
A
28
35
4. Release hopper quick-release clamp (28).
5. Disconnect pump module (A) from frame (35).
6. Remove five screws (12 ) and motor cover (18).
7. Fig. 10. Disconnect transducer connector (B) from
control board (38). Pull strain relief from bracket.
Thread transducer connector through bracket.
8. Fig. 9. Slowly rotate fan blade on back of motor
until connecting rod (45) near bottom of stroke.
Fig. 9
45
76
75
ti4620a
9. Pry retaining spring (76) up on connecting rod (45).
Push pin (75) out with a screwdriver.
10. Fig. 10. Loosen retaining nut (27).
Fig. 10
49
B
38
27
11. Fig. 11. Unscrew pump (31) from bearing housing
(34).
ti4622a
31
203
34
Fig. 11
Repair
See page 19 for pump repair instructions.
Installation
1. Fig. 17. Push piston rod (203) out of pump (31) 50
to 75 mm (2 to 3 inches).
2. Fig. 11. Screw retaining nut (27) onto pump until it
stops. Screw pump (31) into bearing housing (34)
until pump stops. Unscrew pump until pump outlet
is 13_from horizontal, but no more than one turn.
WARNING
MOVING PARTS HAZARD
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 property damage. Make sure pin
and retaining spring are properly installed.
3. Tighten retaining nut (27).
4. Push pin (75) in with a screwdriver. Push retaining
spring (76) down on connecting rod (45).
5. Fig. 10. Connect transducer connector (B) to
motor control board (38).

19309977
Pump Repair
Disassemble Pump
TIP: It may be easier to leave the pump connected to
the connecting rod and bearing housing if the only
assemblies to be cleaned and inspected is the intake
housing or piston valve.
1. Relieve pressure;page 4.
2. See Pump Repair, Removal on page 18 to
remove pump.
3. Fig. 13. Remove clamp (209) and intake
housing (204).
ti5132a
204
209
Fig. 12
4. Remove clamp (209) and pump cylinder (201).
ti5132a
201
209
Fig. 13
5. Fig. 14. Remove packing nut (216). Push piston
rod (203) from outlet housing (202).
ti5131a
216
202
203
Fig. 14
6. Place end of piston rod in vise and remove piston
valve (217). Remove piston seal (222).
Fig. 15
203
222*
217*
220*
ti4804a
7. Inspect all part for nicks and scratches. Replace
worn or damaged parts as they may result in poor
pump performance.
Repair Kit
Piston Seal Repair Kit 248530 is available. Replace all
parts in kit for best results.
Parts included in kit are marked with an asterisk in text
and drawings. For example, 208*.

20 309977
Assemble Pump
1. Fig. 16. Place end of piston rod (203) in vise.
Install new piston seal (222). Torque piston valve
to 27 ft-lb (36.6 Nm).
203
222*
217*
220*
ti4804a
Fig. 16
2. Fig. 17. Install packing nut (216). Hand tighten and
then tap with screw driver. Push piston rod (203)
into outlet housing (202) and extending 50 – 75
mm out of outlet housing.
Fig. 17
ti5131a
216
202
203
ti5131a
203
2–3”
50–75mm
3. Install clamp (209) on pump cylinder (201).
Torque clamp to 25 in-lb (2.82 Nm).
ti5132a
201
209
Fig. 18
4. Install clamp (209) on intake housing (204). Torque
clamp to 25 in-lb.
Fig. 19
ti5132a
204
209
5. See Pump Repair, Installation on page 18 to
install pump.