Graco 309674M Operating instructions

Graco Inc. P.O. Box 1441 Minneapolis, MN 55440-1441
Copyright 2002, Graco Inc. is registered to I.S. EN ISO 9001
309674M
Repair
Electric Airless Sprayers
- For the application of architectural paints and coatings -
3300 psi (227 bar, 22.7 MPa) Maximum Working Pressure
Korean patent: 10-0579681
Important Safety Instructions. Read all warnings and instructions
in this manual. Save these instructions. See page 2 for model
information.
ti2399
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UltraTM 395/495/595
UltraMax IITM 490/495/595
Ultimate MX IITM 490/495/595
ST Max IITM 490/495/595
Ultimate Nova
TM
395
ST MaxTM 395/495/595
Super NovaTM 495/595

Models
2309674M
Models
VAC Model
120
Ultra 395
Ultimate Nova 395
233960
826014
233961 233962
Ultra 495
Super Nova 495
233966
826017
233967
826018
233968
826019
Ultra 595
Super Nova 595
234490
826052
234435
826046
Ultra Max II 490
Ultimate MX II 490
249911
825028
249913
825029
249914
825036
Ultra Max II 495
Ultimate MX II 495
249915
825037
249916
825038
249917
825039
Ultra Max II 595
Ultimate MX II 595
249918
825046
249919
825045
230 CEE
ST Max 395 Hopper 233955
ST Max 395 234176 258662
ST Max 495 233956 233970 233971
ST Max 595 248661 244437
ST Max II 490 Hopper 253011
ST Max II 490 249926 253012 253013
ST Max II 495 249928 253014 249978
ST Max II 595 253015 249930
230
Europe
ST Max 395 223963
ST Max 495 233957 233975
ST Max 595 244436
ST Max II 490 249927
ST Max II 495 249929 249979
ST Max II 595 249931
110 UK
ST Max 395 223972
ST Max 495 233973 233975
ST Max 595 244436
ST Max II 490 249935
ST Max II 495 249936 249980
ST Max II 595 249937
230 Asia
Ultra 395 234180
Ultra 495 234183 234181 234182
Ultra 595 248660 244439
Ultra Max II 490 249932
Ultra Max II 495 249933 253104 253105
Ultra Max II 595 253107 249934
100
Japan
Ultra 495 234186 233974
UltraMax II 495 249938 253106

Warnings
309674M 3
Warnings
The following are general warnings related to the setup, use, grounding, maintenance, and repair of this equipment.
Additional, more specific warnings may be found throughout the body of this manual where applicable. Symbols
appearing in the body of the manual refer to these general warnings. When these symbols appear throughout the
manual, refer back to these pages for a description of the specific hazard.
WARNING
FIRE AND EXPLOSION HAZARD
Flammable fumes, such as solvent and paint fumes, in work area can ignite or explode. To help prevent
fire and explosion:
• Use equipment only in well ventilated area.
• Eliminate all ignition sources; such as pilot lights, cigarettes, portable electric lamps, and plastic drop
cloths (potential static arc).
• Sprayer generates sparks. When flammable liquid is used in or near the sprayer or for flushing or
cleaning, keep sprayer at least 20 feet (6 m) away from explosive vapors.
• Keep work area free of debris, including solvent, rags, and gasoline.
• Do not plug or unplug power cords or turn lights on or off when flammable fumes are present.
• Ground equipment and conductive objects in work area. Read Grounding instructions.
• If there is static sparking or you feel a shock, stop operation immediately. Do not use equipment
until you identify and correct the problem.
• Keep a fire extinguisher in the work area.
ELECTRIC SHOCK HAZARD
Improper grounding, setup, or usage of the system can cause electric shock.
• Turn off and disconnect power cord before servicing equipment.
• Use only grounded electrical outlets.
• Use only 3-wire extension cords.
• Ensure ground prongs are intact on sprayer and extension cords.
• Do not expose to rain. Store indoors.
SKIN INJECTION HAZARD
High-pressure fluid from gun, hose leaks, or ruptured components will pierce skin. This may look like just
a cut, but it is a serious injury that can result in amputation. Get immediate surgical treatment.
• Do not point gun at anyone or at any part of the body.
• Do not put your hand over the spray tip.
• Do not stop or deflect leaks with your hand, body, glove, or rag.
• Engage trigger lock when not spraying.
• Follow Pressure Relief Procedure in this manual, when you stop spraying and before cleaning,
checking, or servicing equipment.

Warnings
4309674M
EQUIPMENT MISUSE HAZARD
Misuse can cause death or serious injury.
• Do not exceed the maximum working pressure or temperature rating of the lowest rated system
component. Read Technical Data in all equipment manuals.
• Use fluids and solvents that are compatible with equipment wetted parts. Read Technical Data in all
equipment manuals. Read fluid and solvent manufacturer’s warnings. For complete information
about your material, request MSDS from distributor or retailer.
• Check equipment daily. Repair or replace worn or damaged parts immediately with genuine Graco
replacement parts only.
• Do not alter or modify equipment.
• Use equipment only for its intended purpose. Call your Graco distributor for information.
• Route hoses and cables away from traffic areas, sharp edges, moving parts, and hot surfaces.
• Do not kink or overbend hoses or use hoses to pull equipment.
• Comply with all applicable safety regulations.
• Keep children and animals away from work area.
• Do not operate the unit when fatigued or under the influence of drugs or alcohol.
PRESSURIZED ALUMINUM PARTS HAZARD
Do not use 1,1,1-trichloroethane, methylene chloride, and/or other halogenated hydrocarbon solvents or
fluids containing such solvents in pressurized aluminum equipment. Such use can cause serious chemi-
cal reaction and equipment rupture, and result in death, serious injury, and/or property damage.
TOXIC FLUID OR FUMES HAZARD
Toxic fluids or fumes can cause serious injury or death if splashed in the eyes or on skin, inhaled, or
swallowed.
• Read MSDS’s to know the specific hazards of the fluids you are using.
• Store hazardous fluid in approved containers and dispose of it according to applicable guidelines.
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:
• Protective eye wear
• Clothing and respirator as recommended by the fluid and solvent manufacturer
•Gloves
• Hearing protection

Component Identification
309674M 5
Component Identification
Model 233960 shown
6
1
8
9
5
4
3
2
7
B

FN Component
1 ON/OFF switch
2Primetube
3 Siphon tube
4 Pressure control
5 Filter
6 Trigger lock
7Pump
8 Fluid outlet
9 Prime/Spray valve
10 Service Tag (below sprayer frame)

Installation
6309674M
Installation
Grounding and Electric
Requirements
The sprayer must be grounded. Grounding reduces the
risk of static and electric shock by providing an escape
wire for the electrical current due to static build up or in
the event of a short circuit.
The sprayer power cord includes a grounding wire with
an appropriate grounding contact.
The plug must be plugged into an outlet that is properly
installed and grounded in accordance with all local
codes and ordinances. Do not use an adapter.
Do not use the sprayer if the electrical cord has a dam-
aged ground prong. Do not modify plug. If it will not fit in
outlet, have a grounded outlet installed by a qualified
electrician.
Power Requirements
• 100-120V units require 100-120VAC, 50/60 Hz,
15A, 1 phase
• 230V units require 230VAC, 50/60 Hz, 7.5A, 1
phase
• Never use an outlet that is not grounded or an
adapter.
Only use an extension cord with an undamaged
ground contact. If an extension cord is necessary, use a
3-wire, 12 AWG (2.5 mm2) minimum.
Spray gun:ground through connection to a properly
grounded fluid hose and pump.
Fluid supply container:follow local code.
Solvent and oil-based fluids: follow local code. Use
only conductive metal pails, placed on a grounded sur-
face such as concrete.
Do not place the pail on a nonconductive surface, such
as paper or cardboard, which interrupts grounding conti-
nuity.
Grounding the metal pail: connect a ground wire to the
pail by clamping one end to pail and other end to ground
such as a water pipe.
Maintain grounding continuity when flushing or
relieving pressure: hold metal part of the spray gun
firmly to the side of a grounded metal pail, then trigger
the gun.
TIC
Smaller gauge or longer extension cords may
reduce sprayer performance.

Operation
309674M 7
Operation
Pressure Relief Procedure
To reduce risk of injury from injection, follow this proce-
dure whenever you are instructed to relieve pressure,
stop spraying, service equipment or install or clean
spray tip. Read warnings, page 3.
1. Turn power switch OFF and unplug power cord.
2. Turn pressure to lowest setting. Hold gun to side of
grounded metal flushing bucket. Trigger gun to
relieve pressure, turn prime valve down.
\
3. Engage gun trigger lock if unit is being shut down or
left unattended.
If you suspect the spray tip or hose is clogged or that
pressure has not been fully relieved after following the
steps above, VERY SLOWLY loosen tip guard retaining
nut or hose end coupling to relieve pressure gradually,
then loosen completely. Clear hose or tip obstruction.
ti2707a
ti2718a
Leave Spray - Prime/Drain valve in the
PRIME/DRAIN position until you are ready to spray
again.
ti2614a
-
FLUSH
ti2599a
ti2

General Repair Information
8309674M
General Repair Information
Flammable materials spilled on hot, bare motor could
cause fire or explosion. To reduce risk of burns, fire or
explosion, do not operate sprayer with cover removed.
• Keep all screws, nuts, washers, gaskets, and electri-
cal fittings removed during repair procedures. These
parts usually are not provided with replacement kits.
• Test repairs after problems are corrected.
• If sprayer does not operate properly, review repair
procedure to verify you did it correctly. See Trouble-
shooting, page 9.
• Install motor shroud before operation of sprayer and
replace if damaged. Motor shroud directs cooling air
around motor to prevent overheating. It can reduce
risk of burns, fire or explosion, or cut fingers.
To reduce risk of serious injury, including electric shock:
• Do not touch moving or electric parts with fingers or
tools while testing repair.
• Unplug sprayer when power is not required for test-
ing.
• Install all covers, gaskets, screws and washers
before you operate sprayer.
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 or pressure control. Do not
pinch wires between cover and control box.
CAUTION
• Do not run sprayer dry for more than 30 seconds.
Doing so could damage pump packings.
• Protect the internal drive parts of this sprayer from
water. Openings in the cover allow for air cooling of
the mechanical parts and electronics inside. If
water gets in these openings, the sprayer could
malfunction or be permanently damaged.
• Prevent pump corrosion and damage from freezing.
Never leave water or water-base paint in sprayer
when its not in use in cold weather. Freezing fluids
can seriously damage sprayer. Store sprayer with
Pump Armor to protect sprayer during storage.

Troubleshooting
309674M 9
Troubleshooting
Type of Problem
What to Check
(if check is OK, go to next)
What to Do
(When check is not OK, refer to this
column)
Basic fluid pressure problems Pressure control knob setting. Motor
will not run if at minimum setting (fully
counter-clockwise).
Slowly increase pressure to see if
motor starts.
Spray tip or fluid filter may be
clogged.
Relieve pressure, page 7 and clear
clog, or clean filter; refer to separate
gun or tip instruction manual.
Basic Mechanical Problems Pump frozen or paint hardened in
pump.
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
15, Displacement Pump Replace-
ment.
Displacement pump connecting rod
pin must be completely pushed into
connecting rod and retaining spring
must be firmly in groove of pump pin.
See page 15.
Push pin into place and secure with
spring retainer.
Motor. Remove drive housing assem-
bly. See page 17. Try to rotate fan by
hand.
Replace motor if fan won’t turn. See
page 19.
Motor control board. Board shuts
down and displays error code.
See Motor Control Board Diagnos-
tics, page 27.

Troubleshooting
10 309674M
Basic Electrical Problems Electric supply. Meter must read:
• 210-255 VAC for 220-240V
models
• 85-130 VAC for 100-120V
models.
Reset building circuit breaker.
Replace building fuse. Try another
outlet.
Extension cord. Check extension
cord continuity with volt meter.
Replace extension cord.
Sprayer power supply cord. Inspect
for damage such as insulation or
wires.
Replace power supply cord, page 24.
Motor leads are securely fastened
and properly mated.
Replace loose terminals; crimp to
leads. Be sure terminals are firmly
connected.
Clean circuit board terminals.
Securely reconnect leads.
Basic Electrical Problems - These
problems only apply to Ultra, Nova
and STMax 395/495/595 model
sprayers with brush motors. They do
not apply to UltraMax II, Ultimate
MX II and ST Max II 490/495/595
model sprayers.
Motor armature for shorts using
armature tester (growler) or perform
spin test. See page 18.
Replace motor. See page 29.
For loose motor brush lead connec-
tions and terminals.
Tighten terminal screws. Replace
brushes if leads are damaged.
Brush length which must be 1/2 in.
minimum. NOTE: Brushes do not
wear at the same rate on both sides
of motor. Check both brushes.
Replace brushes, page 20.
Broken or misaligned motor brush
springs. Rolled portion of spring must
rest squarely on top of brush.
Replace spring if broken. Realign
spring with brush.
Motor brushes may be binding in
brush holders.
Clean brush holders. Remove carbon
with small cleaning brush. Align
brush leads with slot in brush holder
to assure free vertical brush move-
ment.
Motor armature commutator for burn
spots, gouges or extreme roughness.
Remove motor and have motor shop
resurface commutator if possible.
See page 29.
Type of Problem
What to Check
(if check is OK, go to next)
What to Do
(When check is not OK, refer to this
column)

Troubleshooting
309674M 11
Note: for the following electric prob-
lems, refer to wiring diagram, page
22, 23, and 24 to identify Test Points
(TP).
Power supply cord. Connect volt
meter between TP1 (neutral) and
TP2. Plug in sprayer. Meter must
read:
• 210-255 VAC for 220-240V
models
• 85-130 VAC for 100-120V
models.
Unplug sprayer.
Replace power supply cord, page 24.
ON/OFF Switch. Connect volt meter
between L1 and L2 terminal on
ON/OFF switch. Plug in sprayer and
turn ON. Meter must read:
• 210-255 VAC for 220-240V
models
• 85-130 VAC for 100-120V
models.
Replace ON/OFF switch. See page
22.
All terminals for damage or loose fit. Replace damaged terminals and
reconnect securely.
Low Output For worn spray tip. Relieve pressure, page 7. Then
replace tip. See your separate gun
manual for additional instruction.
Verify pump does not continue to
stroke when gun trigger is released.
Service pump. See page 15.
Filter clogged. Relieve pressure, page 7. Check
and clean filter.
Prime valve leaking. Relieve pressure, page 7. Repair
prime valve.
Suction hose kinks and/or loose
connection.
Correct kink and/or tighten any loose
connections.
Electric supply with volt meter. Low
voltages reduce sprayer
performance. Meter must read:
• 210-255 VAC for 220-240V
models
• 85-130 VAC for 100-120V
models.
Reset building circuit breaker;
replace building fuse. Repair
electrical outlet or try another outlet.
Extension cord size and length; must
be at least 12 gauge wire and no
longer than 300 ft. Longer cord
lengths reduce sprayer performance.
Replace with a correct, grounded,
extension cord.
Type of Problem
What to Check
(if check is OK, go to next)
What to Do
(When check is not OK, refer to this
column)

Troubleshooting
12 309674M
Low Output Leads from motor to pressure control
circuit board for damaged or loose
wires or connectors. Inspect wiring
insulation and terminals for signs of
overheating.
Be sure male terminal blades are
centered and firmly connected to
female terminals. Replace any loose
terminal or damaged wiring. Securely
reconnect terminals.
Low stall pressure. 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.
These problems only apply to Ultra,
Nova and STMax 395/495/595
model sprayers with brush motors.
They do not apply to UltraMax II,
Ultimate MX II and ST Max II
490/495/595 model sprayers.
Motor armature for shorts by using an
armature tester (growler) or perform
spin test. See page 18.
Replace motor. See page 29.
Loose motor brushes and terminals. Tighten terminal screws. Replace
brushes if leads are damaged.
Worn motor brushes. (Brushes must
be 1/2 in. minimum.)
Replace brushes.
Broken and misaligned motor brush
springs. Rolled portion of spring must
rest squarely on top of brush.
Replace spring if broken. Realign
spring with brush.
Motor brushes are binding in brush
holders.
Clean brush holders, remove carbon
dust with small cleaning brush. Align
brush lead with slot in brush holder
to assure free vertical brush
movement.
Motor runs and pump strokes Low paint supply. Refill and reprime pump.
Intake strainer clogged. Remove and clean, then reinstall.
Suction tube or fittings loose. Tighten; use thread sealant or
sealing tape on threads if necessary.
See if intake valve ball and piston ball
are seating properly. See pump
manual.
Remove intake valve and clean.
Check balls and seats for nicks,
replace if necessary. Strain paint
before using to remove particles that
could clog pump. See pump manual.
Leaking around throat packing nut
which may indicate worn or damaged
packings. See pump manual.
Replace packings. Also check piston
valve seat for hardened paint or nicks
and replace if necessary. Tighten
packing nut/wet-cup. See pump
manual.
Pump rod damage. Replace pump, page 15.
Type of Problem
What to Check
(if check is OK, go to next)
What to Do
(When check is not OK, refer to this
column)

Troubleshooting
309674M 13
Motor runs but pump does not stroke Displacement pump pin damaged or
missing.
Replace pump pin if missing. Be sure
retainer spring is fully in groove all
around connecting rod, page 15.
Connecting rod assembly damaged. Replace connecting rod assembly.
See pump manual.
Gears or drive housing, page 17. Inspect drive housing assembly and
gears for damage and replace if
necessary, page 17.
Motor is hot and runs intermittently Determine if sprayer was operated at
high pressure with small tips, which
causes low motor RPM and
excessive heat buildup.
Decrease pressure setting or
increase tip size.
Be sure ambient temperature where
sprayer is located is not more than
90°F (32.22°C) and sprayer is not
located in direct sun.
Move sprayer to shaded, cooler area
if possible.
Building circuit breaker opens as
soon as sprayer switch is turned on
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 replacing
control board.
All electrical wiring for damaged
insulation and all terminals for loose
fit or damage. Also, wires between
pressure control and motor. See
page 28.
Repair or replace any damaged
wiring or terminals. Securely
reconnect all wires.
For missing inspection plate gasket,
see page 26, bent terminal forks or
other metal to metal contact points
which case a short.
Correct faulty conditions.
Motor control board by performing
control board diagnostics. See page
14. If diagnostics indicate, substitute
with a good board.
CAUTION: Do not perform this check
until motor armature is determined to
be good. A bad motor armature can
burn out a good board.
Replace with a new pressure control
board. See page 26.
Building circuit breaker opens as
soon as sprayer switch is turned on
This problem only applies to Ultra,
Nova and STMax 395/495/595
model sprayers with brush motors.
They do not apply to UltraMax II,
Ultimate MX II and ST Max II
490/495/595 model sprayers.
Motor armature for shorts. Use an
armature tester (growler) or perform
spin test. See page14. Inspect
windings for burns.
Replace motor. See page 29.
Building circuit breaker opens as
soon as sprayer is plugged into outlet
and sprayer is NOT turned on.
Basic Electric Problems, page 9 of
Troubleshooting.
Perform necessary procedures.
Type of Problem
What to Check
(if check is OK, go to next)
What to Do
(When check is not OK, refer to this
column)

Troubleshooting
14 309674M
ON/OFF switch. See page 22. Be
sure sprayer is unplugged!
Disconnect wires from switch. Check
switch with ohmmeter. Reading must
be infinity with ON/OFF switch OFF,
and zero when switch is ON.
Replace ON/OFF switch. See page
22.
For damaged or pinched wires in
pressure control. See page 26.
Replace damaged parts. See page
26.
Sprayer quits after sprayer operates
for 5 to 10 minutes.
Basic Electric Problems, page 9 of
Troubleshooting.
Perform necessary procedures.
Electrical supply volt meter. Meter
must read:
• 210-255 VAC for 220-240V
models
• 85-130 VAC for 100-120V
models.
If voltage is too high, do not operate
sprayer until corrected.
Tightness of pump packing nut. Over
tightening tightens packings on rod,
restricts pump action, and overloads
motor.
Loosen packing nut. Check for
leaking around throat. Replace pump
packings, if necessary. See pump
manual.
Type of Problem
What to Check
(if check is OK, go to next)
What to Do
(When check is not OK, refer to this
column)

Displacement Pump Replacement
309674M 15
Displacement Pump Replacement
See manual 309053 for pump repair instructions.
Removal
1. Flush pump (13).
1. Relieve pressure, page 7.
2. (Style A) Loosen screws (12) and rotate cover (70).
Note: Style A is shown in most illustrations.
(Style B) Loosen screws (12). Push cover (70) up
and pull off sprayer.
3. Remove suction tube (60) and hose (45).
4. Cycle motor until pump pin (32)is in position to be
removed.
5. Disconnect power cord from outlet.
6. Using a flat screwdriver, push retaining spring (31)
up. Push out pump pin (32).
7. Loosen pump jam nut (29). Unscrew and remove
pump (41).
Style A Style B
12
70 70
60
45
WLD
32
32
31
TIA
12 41
29

Displacement Pump Replacement
16 309674M
Installation
1. Extend pump piston rod full. Apply grease to top of
pump rod at (A) or inside connecting rod (43). Install
jam nut (29) on pump threads.
2. Install pump rod (A) into connecting rod (43).
3. Install pump pin (32). Slide retainer spring (31)
down into groove over pump pin.
4. Push pump (41) up until pump threads engage.
5. Screw in pump until threads are flush with top of
drive housing opening.
6. Align pump outlet to back.
7. Turn jam nut (29) counter-clockwise until it stops.
Tighten jam nut by hand, then tap 1/8 to 1/4 turn
with a 20 oz (maximum) hammer to approximately
75 ft-lb (102 N•m).
8. Install suction tube (60) and high pressure hose
(45). Tighten fittings.
.
9. Fill packing nut with Graco TSL until fluid flows onto
top of seal.
10. (Style A) Rotate cover (70). Tighten screws (12).
(Style B) Replace cover (70) over screws. Push
cover down into place. Tighten screws (12).
WARNING
If pump pin works loose, parts could break off due to
force of pumping action. Parts could project through
air and result in serious injury or property damage.
CAUTION
If the pump jam nut loosens during operation, the
threads of the drive housing will be damaged.
WLD
A
TIA
43
A
29
32
31
WLD
29
60
45
WLD
12
70

Drive Housing Replacement
309674M 17
Drive Housing Replacement
Removal
1. Relieve pressure, page 7.
2. Disconnect power cord from outlet.
3. Remove screws (12) and pump rod cover (70).
4. Remove pump (41), Displacement Pump Replace-
ment, page 15
5. Remove screws (12) from shroud (23).
6. Remove screws (12) from front cover (22).
7. Remove screws (47).
8. Pull drive housing (42) off motor (54).
9. Remove gear cluster (44) and (40) and thrust
washer (25) from drive housing.
Installation
1. Apply a heavy coat of grease to gears and needle
bearing surfaces.
2. Install washers (8, 10) on back of gear (40). Install
gear in motor end bell. Using grease for retention,
place washer (10) over bearing inside housing (42).
3. Install washers (1, 9) on back of gear (44). Install in
motor endbell.
4. Install thrust washer (25) on gear (44).
5. Push drive housing (42) on motor endbell as you
guide gear crank (44) through hole in connecting
rod (43).
6. Install screws (47).
7. Install cover (22) and screws (12).
8. Install shroud (23) and screws (12).
9. Install pump (41); Displacement Pump Replace-
ment, page 15.
10. Install pump rod cover (70) with screws (12).
CAUTION
Do not drop gear cluster (44) and (40) when removing
from drive housing (42). Gear cluster may stay
engaged in motor front end bell or drive housing.
TIC

!





 









Motor Diagnostics
18 309674M
Motor Diagnostics
Spin Test
*Note: Motors used in the UltraMax II, Ultimate MX II and ST Max II 490/495/595 model sprayers are brushless. The
following brush information and instructions apply to Ultra, Nova and ST Max 395/495/595 model sprayers only.
Check for electrical continuity in motor armature, windings and brush* as follows:
If Motor Diagnostics reveal a damaged motor or if motor brushes* are shorter than 1/2 in. (12.7 mm) or if the motor
shaft cannot turn, replace the motor, page 29.
Setup
1. Relieve pressure, page 7.
2. Unplug electric cord.
3. Remove drive housing, Drive Housing Replace-
ment, page 17.
4. Remove pressure control cover (50). Disconnect
connector F.
5. Remove four screws (12) and motor shroud (23)
and inspection covers.
Armature Short Circuit Test
Quickly turn motor fan by hand. If not shorted, motor will
coast two or three revolutions before complete stop. If
motor does not spin freely, armature is shorted. Replace
motor, page 29.
Armature, Brushes and Motor Wiring Open Circuit
Test (Continuity)
1. Connect red and black motor leads together with
test lead.
2. Turn motor fan by hand, about two revolutions per
second.
3. If there is an uneven resistance or no resistance,
check for broken brush springs*, brush leads*; loose
brush terminal screws*, worn brushes*, or motor
lead terminals. Repair as needed, page 20.
4. If still uneven, or no resistance, replace motor using
Motor Kit, page 29.
WLD
F
50

Fan Replacement
309674M 19
Fan Replacement
Removal
1. Relieve pressure, page 7. Disconnect power cord
from outlet.
2. Remove four screws (12) and shroud (23).
3. Loosen tensioning screw (126) on fan (125).
4. Pull off fan (77).
Installation
1. Slide new fan (125) in place on back of motor. Be
sure blades of fan face motor as shown.
2. Tighten screw (126).
3. Replace shroud (23) and four screws (12).
TIA
12
23
125
126

Motor Brush Replacement
20 309674M
Motor Brush Replacement
Note: Motors used in the UltraMax II, Ultimate MX II and ST Max II 490/495/595 model sprayers are brushless. The
following brush information and instructions apply to Ultra, Nova and ST Max 395/495/595 model sprayers only.
The Utlra, Nova and ST Max 395/495/595 sprayer’s motors are supplied by two different motor manufacturers. Style
A motor has brush caps held on with screws. Style B has brush caps that snap onto the motor. Determine which style
motor you are servicing and refer to the appropriate illustration in the following instructions.
Motor Brush Removal
Replace brushes worn to less than 1/2 in. Brushes wear
differently on each side of motor, check both sides.
Brush Repair Kit 287735 is available.
1. Read General Repair Information, page 8.
2. Relieve pressure, page 7.
3. Remove motor shroud and two inspection covers
(A).
4. Push clip spring (B) to release hook (C) from brush
holder (D). Pull out spring clip (B).
5. Pull brush lead (E) off terminal (F). Remove brush
(G).
6. 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.
WLD
WLD
A
Style A
Style B
WLD
BC
D
E
F
G
Style A



Included in Brush Repair Kit
Minimum 0.5 in. (12.5 mm)

WLD
Style B
B
C
G
E
F
D






Motor lead; do not disconnect
Minimum 0.5 in. (12.5 mm)
Included in Brush Repair Kit