Graco LTS 15 Use and care manual

Repair and Parts
LTS 15, LTS 17, ProLTS 17 and
ProLTS 19 Airless Sprayers
- For portable spray applications of architectural paints and coatings -
LTS 15 & LTS 17 Models ONLY: Use water-based or
mineral spirit-type materials only. Do not use materials
having flash points lower than 70° F (21° C). This
includes, but is not limited to, acetone, xylene, toluene, or
naptha. For more information about your material, request
MSDS from distributor or retailer.
Models 257060, 257065, 257070, 257080,
24N906, 24N808
3000 psi (21 MPa, 207 bar) Maximum Working Pressure
See page 2 for model and series information including
dispense rate, recommended hose length, guns, and
maximum working pressure.
IMPORTANT SAFETY INSTRUCTIONS.
Read all warnings and instructions in this
manual. Save these instructions.
Related Manual
313034
Series A, B, C
Model: 257060
MAGNUM LTS 15
ti11304a
MAGNUM ProLTS 19
Model: 24N808
ti9368b
MAGNUM LTS 17
Model: 257065
ti11305a
Series A, B Series A
MAGNUM ProLTS 17
Model: 257070
Series A
ti9369a
ti9368a
MAGNUM ProLTS 19
Model: 257080
Series A
ti9369b
MAGNUM ProLTS 17
Series A
Model: 24N906
Visit our website;
http://MAGNUMLTS.Graco.com
313036N
EN

Specifications
2313036N
Specifications
This equipment is not intended for use with flammable or combustible materials used in places such as cabinet
shops or other “factory”, or fixed locations. If you intend to use this equipment in this type of application, you must
comply with NFPA 33 and OSHA requirements for the use of flammable and combustible materials.
Getting Started
Fold-n-Store™Cart (ProLTS Sprayers Only)
1. Unfold Fold-n-Store
handle (a) and align
as shown.
2. Tighten wingnuts (b).
3. Grasp cart handle
securely with one hand.
With the other hand, lift
and pull handle (a)
located in front of
sprayer frame, toward
you. Lift up front of
sprayer until you hear a
click and the cart is
locked in place.
4. Install hose rack (d) to frame
handle. Install lock nuts.
Tighten securely.
5. Secure power cord in clip
(e) located underneath
storage compartment.
Model Name Series
Dispense Rate
gpm (lpm)
Hose Length and
Diameter
Gun
Model
Maximum Working
Pressure
PSI MPa bar
MAGNUM
LTS 15 A, B, C 0.27 gpm
(1.02 lpm)
1/4 in. x 25 ft
(6.4 mm x 7.5 m) SG2 3000 21 207
MAGNUM
LTS 17 A, B 0.31 gpm (1.17 lpm)
1/4 in. x 25 ft
(6.4 mm x 7.5 m) SG2 3000 21 207
MAGNUM
ProLTS 17 A0.34 gpm (1.29 lpm)
1/4 in. X 50 ft
(6.4 mm x 15 m) SG3 3000 21 207
MAGNUM
ProLTS 19 A0.38 gpm (1.44 lpm)
1/4 in. X 50 ft
(6.4 mm x 15 m) SG3 3000 21 207
a
bti9675a
cti9679a
d
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e

Warnings
313036N 3
Warnings
The following warnings are for the setup, use, grounding, maintenance, and repair of this equipment. The exclama-
tion point symbol alerts you to a general warning and the hazard symbols refer to procedure-specific risks. Refer
back to these warnings. Additional, product specific warnings may be found throughout the body of this manual
where applicable.
WARNING
GROUNDING
This product must be grounded. In the event of an electrical short circuit, grounding reduces the risk of
electric shock by providing an escape wire for the electric current. This product is equipped with a cord
having a grounding wire with an appropriate grounding plug. The plug must be plugged into an outlet that is
properly installed and grounded in accordance with all local codes and ordinances.
• Improper installation of the grounding plug is able to result in a risk of electric shock.
• When repair or replacement of the cord or plug is required, do not connect the grounding wire to either
flat blade terminal.
• The wire with insulation having an outer surface that is green with or without yellow stripes is the
grounding wire.
• Check with a qualified electrician or serviceman when the grounding instructions are not completely
understood, or when in doubt as to whether the product is properly grounded.
• Do not modify the plug provided; if it does not fit the outlet, have the proper outlet installed by a quali-
fied electrician.
• This product is for use on a nominal 120V circuit and has a grounding plug similar to the plug illustrated
in the figure below.
• Only connect the product to an outlet having the same configuration as the plug.
• Do not use an adapter with this product.
Extension Cords:
• Use only a 3-wire extension cord that has a 3-blade grounding plug and a 3-slot receptacle that
accepts the plug on the product.
• Make sure your extension cord is not damaged. If an extension cord is necessary, use 12 AWG
(2.5 mm2) minimum to carry the current that the product draws.
An undersized cord results in a drop in line voltage and loss of power and overheating.
ti9164a

Warnings
4313036N
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:
• Do not spray flammable or combustible materials near an open flame or sources of ignition such as
cigarettes, motors, and electrical equipment. For LTS 15 and LTS 17 models: only use water-based
or mineral spirit-type materials with a flash point greater than 70°F (21°C).
• Paint or solvent flowing through the equipment is able to result in static electricity. Static electricity
creates a risk of fire or explosion in the presence of paint or solvent fumes. All parts of the spray
system, including the pump, hose assembly, spray gun, and objects in and around the spray area
shall be properly grounded to protect against static discharge and sparks. Use Graco conductive or
grounded high-pressure airless paint sprayer hoses.
• Verify that all containers and collection systems are grounded to prevent static discharge.
• Connect to a grounded outlet and use grounded extensions cords. Do not use a 3-to-2 adapter.
• Do not use a paint or a solvent containing halogenated hydrocarbons.
• Keep spray area well-ventilated. Keep a good supply of fresh air moving through the area. Keep pump
assembly in a well ventilated area. Do not spray pump assembly.
• Do not smoke in the spray area.
• Do not operate light switches, engines, or similar spark producing products in the spray area.
• Keep area clean and free of paint or solvent containers, rags, and other flammable materials.
• Know the contents of the paints and solvents being sprayed. Read all Material Safety Data Sheets
(MSDS) and container labels provided with the paints and solvents. Follow the paint and solvents
manufacturer’s safety instructions.
• Fire extinguisher equipment shall be present and working.
• 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.
SKIN INJECTION HAZARD
High-pressure spray is able to inject toxins into the body and cause serious bodily injury. In the event that
injection occurs, get immediate surgical treatment.
• Do not aim the gun at, or spray any person or animal.
• Keep hands and other body parts away from the discharge. For example, do not try to stop leaks with
any part of the body.
• Always use the nozzle tip guard. Do not spray without nozzle tip guard in place.
• Use Graco nozzle tips.
• Use caution when cleaning and changing nozzle tips. In the case where the nozzle tip clogs while
spraying, follow the Pressure Relief Procedure for turning off the unit and relieving the pressure
before removing the nozzle tip to clean.
• Do not leave the unit energized or under pressure while unattended. When the unit is not in use, turn
off the unit and follow the Pressure Relief Procedure for turning off the unit.
• Check hoses and parts for signs of damage. Replace any damaged hoses or parts.
• This system is capable of producing 3000 psi. Use Graco replacement parts or accessories that are
rated a minimum of 3000 psi.
• Always engage the trigger lock when not spraying. Verify the trigger lock is functioning properly.
• Verify that all connections are secure before operating the unit.
• Know how to stop the unit and bleed pressure quickly. Be thoroughly familiar with the controls.
WARNING

Warnings
313036N 5
EQUIPMENT MISUSE HAZARD
Misuse can cause death or serious injury.
• Do not operate the unit when fatigued or under the influence of drugs or alcohol.
• Do not exceed the maximum working pressure or temperature rating of the lowest rated system com-
ponent. See Technical Data in all equipment manuals.
• 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. For complete information about
your material, request MSDS from distributor or retailer.
• Do not leave the work area while equipment is energized or under pressure (If applicable.)
• Turn off all equipment and follow the Pressure Relief Procedure when equipment is not in use.
• Check equipment daily. Repair or replace worn or damaged parts immediately with genuine manufac-
turer’s replacement parts only.
• Do not alter or modify equipment. Alterations or modifications may void agency approvals and create
safety hazards.
• Make sure all equipment is rated and approved for the environment in which you are using it.
• Use equipment only for its intended purpose. Call your distributor for information.
• Route hoses and cables away from traffic areas, sharp edges, moving parts, and hot surfaces.
• Do not kink or over bend hoses or use hoses to pull equipment.
• Keep children and animals away from work area.
• Comply with all applicable safety regulations.
ELECTRIC SHOCK HAZARD
This equipment must be grounded.Improper grounding, setup, or usage of the system can cause electric
shock.
• Turn off and disconnect power cord before servicing equipment.
• Connect only to grounded electrical outlets.
• Use only 3-wire extension cords.
• Ensure ground prongs are intact on power and extension cords.
• Do not expose to rain. Store indoors.
PRESSURIZED ALUMINUM PARTS HAZARD
Use of fluids that are incompatible with aluminum in pressurized equipment can cause serious chemical
reaction and equipment rupture. Failure to follow this warning can result in death, serious injury, or prop-
erty damage.
• Do not use 1,1,1-trichloroethane, methylene chloride, other halogenated hydrocarbon solvents or flu-
ids containing such solvents.
• Many other fluids may contain chemicals that can react with aluminum. Contact your material supplier
for compatibility.
BURN HAZARD
Equipment surfaces and fluid that’s heated can become very hot during operation. To avoid severe burns:
• Do not touch hot fluid or equipment.
MOVING PARTS HAZARD
Moving parts can pinch, cut or amputate fingers and other body parts.
• Keep clear of moving parts.
• Do not operate equipment with protective guards or covers removed.
• Pressurized equipment can start without warning. Before checking, moving, or servicing equipment,
follow the Pressure Relief Procedure and disconnect all power sources.
WARNING

Warnings
6313036N
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 swal-
lowed.
• Read MSDSs 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
Wear appropriate protective equipment when in the work area to help prevent serious injury, including eye
injury, hearing loss, inhalation of toxic fumes, and burns. This protective equipment includes but is not lim-
ited to:
• Protective eyewear, and hearing protection.
• Respirators, protective clothing, and gloves as recommended by the fluid and solvent manufacturer
CALIFORNIA PROPOSITION 65
The engine exhaust from this product contains a chemical known to the State of California to cause
cancer, birth defects or other reproductive harm. Wash hands after handling.
WARNING

Notes
313036N 7
Notes

Component Identification
8313036N
Component Identification
A Airless spray gun Sprays fluid.
B Power switch Turns sprayer ON and OFF.
C Pressure control knob Increases (clockwise) and decreases (counter-clockwise) fluid pres-
sure in pump, hose, and spray gun.
C1 Setting Indicator
To select function, align symbol on pressure control knob with set-
ting
indicator, page 11.
D Pump fluid outlet fitting Threaded connection for paint hose.
EInstaClean™fluid filter
(ProLTS Sprayers Only)
• Filters fluid coming out of pump to reduce tip plugging and
improve finish.
• Self cleans only during pressure relief.
F
Power-Piston™Pump (behind Easy
Access door, not shown)
(ProLTS Sprayers Only)
Pumps and pressurizes fluid and delivers it to paint hose.
F1 Easy Access™door
(ProLTS Sprayers Only)
Easy Access door permits quick access to outlet valve. To remove
door, insert flat blade of screwdriver into slot on the bottom of the
door (as shown on page 8).
G Suction tube Draws fluid from paint pail into pump.
H Prime tube (with diffuser) Drains fluid in system during priming and pressure relief.
J Prime/Spray valve
• In PRIME position (pointing down) directs fluid to prime tube.
• In SPRAY position (pointing forward) directs pressurized fluid
to paint hose.
• Automatically relieves system pressure in overpressure
situations.
K
Storage compartment
(ProLTS 257070,257080 Sprayers
Only)
Provides onboard storage for spray tips and/or tools.
L Inlet screen Prevents debris from entering pump.
M Paint hose Transports high-pressure fluid from pump to spray gun.
N
Fold-n-Store™Cart
(ProLTS 257070,257080 Sprayers
Only)
Folding cart frame for hanging on wall.
Q Tip guard Reduces risk of fluid injection injury.
R Reversible spray tip
• Atomizes fluid being sprayed, forms spray pattern and controls
fluid flow according to hole size.
• Reverse unclogs plugged tips without disassembly.
S Gun trigger safety lever (page 11) Prevents accidental triggering of spray gun.
T Gun fluid inlet fitting Threaded connection for paint hose.
U Power Flush attachment Connects garden hose to suction tube for power flushing water-base
fluids.
V Gun fluid filter Filters fluid entering spray gun to reduce tip clogs.
WHose wrap Rack (LTS 17, ProLTS 17,
and ProLTS 19 Only) Stows paint hose.
XPail hanger (LTS 17, ProLTS 17, and
ProLTS 19 Only) For transporting pail by its handle.
AA QuickAccess™Inlet
(ProLTS 19 257080 Only) Permits quick access to inlet valve to clear debris.

Component Identification
313036N 9
J
ED
X
B
K
W
F
C
G
L
H
Q
R
A
S
T
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ti11988a
ti11987a
M
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C1
V
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ti9670a
F1
U
AA
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N
ProLTS Series A shown
SG2/SG3

Installation
10 313036N
Installation
Grounding and Electric
Requirements
Sprayer must be grounded. Grounding reduces the risk
of static and electric shock by providing an escape wire
for electrical current due to static build up or in the event
of a short circuit.
• This sprayer requires
a 120 Vac, 60 Hz,
15A circuit with a
grounding receptacle.
• Never use an outlet
that is not grounded
or an adapter.
• Do not use the sprayer if the
electrical cord has a damaged
ground prong.
• Only use an extension cord with
an undamaged 3-prong plug.
Recommended extension cords
for use with this sprayer:
• 50 ft (15.0 m) 14 AWG (2.1 mm2)
• 100 ft (30.0 m) 12 AWG (3.3 mm2)
Spray gun:ground through connection to a properly
grounded fluid hose and pump.
NOTE: Smaller gauge or longer extension cords may
reduce sprayer performance.
Fluid supply container:follow local code.
Solvent pails used when flushing: follow local code.
Use only conductive metal pails, placed on a grounded
surface such as concrete. Do not place the pail on a
nonconductive surface, such as paper or cardboard,
which interrupts grounding continuity.
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.
Maintaining 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.
Thermal Overload
Motor has a thermal overload switch to shut itself down
if overheated. If unit overheats, allow approximately 45
minutes for unit to cool. Once cool, switch will close and
unit will restart.
ti5573a
ti5572a
To reduce risk of injury from motor starting
unexpectedly when it cools, always turn power switch
OFF if motor shuts down.
ti11986a

Operation
313036N 11
Operation
See Operation manual 312001 for basic information on
sprayer set-up, flushing, and storage.
Trigger Lock
Always engage the trigger lock when you stop spraying
to prevent the gun from being triggered accidentally by
hand or if dropped or bumped.
Pressure Relief Procedure
Follow this Pressure Relief Procedure whenever you
stop spraying and before cleaning, checking, servicing,
or transporting equipment.
1. Turn power switch OFF and unplug
power cord.
2. Turn Prime/Spray valve to
PRIME to relieve pressure.
3. Hold gun firmly to side of pail.
Trigger the gun to relieve pres-
sure.
4. Engage trigger lock.
NOTE: Leave Prime/Spray valve in the PRIME position
until you are ready to spray again.
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.
Read Unclogging Spray Tip instructions in the Sprayer
or Gun Operation manual.
Pressure Control Knob Settings
NOTE: To select function, align symbol on pressure control knob with setting indicator on sprayer.
ti8908a ti8909a
Trigger Locked Trigger Unlocked
ti2018a
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High Pressure
Spray
Low Pressure
Spray
Prime/
Clean
Rolling
ti5597a

General Repair Information
12 313036N
General Repair Information
• Keep all screws, nuts, washers, gaskets, and elec-
trical fittings removed during repair procedures.
These parts usually are not provided with replace-
ment kits.
• Test repairs after problems are corrected.
• If sprayer does not operate properly, review repair
procedure to verify you did it correctly. See Basic
Troubleshooting, page 13 and Advanced Trou-
bleshooting, page 18.
• Overspray may build up in the air passages.
Remove any overspray and residue from air pas-
sages and openings in the enclosures whenever
you service sprayer.
• Do not operate the sprayer without the cover in
place. Replace if damaged. Covers direct cooling air
around motor to prevent overheating
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.
To reduce risk of serious injury, including electric
shock:
• Do not touch moving or electric pars with fingers or
tools while testing repair.
• Unplug sprayer when power is not required for
testing.
• Install all covers, gaskets, screws and washers
before you operate sprayer.
NOTICE
• 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 malfunc-
tion 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.

Basic Troubleshooting
313036N 13
Basic Troubleshooting
Check everything in this Basic Troubleshooting table before you bring the sprayer to a Graco/MAGNUM authorized
service center.
Problem Cause Solution
Power switch is on and sprayer is
plugged in, but motor does not run,
and pump does not cycle.
Pressure is set at zero pressure. Turn pressure control knob clock-
wise to increase pressure setting.
Electric outlet is not providing
power.
• Check that lighted plug on
sprayer is lit (this indicates
electric power at outlet).
• Reset building circuit breaker or
replace fuse.
Extension cord is damaged. Replace extension cord. Read
Grounding and Electric Require-
ments, page 10.
Sprayer electric cord is damaged. Check for broken insulation or
wires. Replace electric cord if dam-
aged.
Motor or control is damaged. Take sprayer to Graco/MAGNUM
authorized service center.

Basic Troubleshooting
14 313036N
Pump does not prime. Prime/Spray Valve is in SPRAY
position.
Turn Prime/Spray Valve to PRIME
position (pointing down).
Inlet screen is clogged or suction
tube is not immersed.
Clean debris off inlet screen and
make sure suction tube is immersed
in fluid.
Pump was not primed with flushing
fluid.
Remove suction tube from paint.
Prime pump with water or sol-
vent-based flushing fluid, see Oper-
ation manual 313034.
Inlet valve check ball is stuck. Remove suction tube and place a
pencil into the inlet section to dis-
lodge the ball, allowing pump to
prime properly. Or, Power Flush
sprayer, see Operation manual
313034.
AutoPrime may need replacement.
Turn power switch ON and listen for
“tap” in pump. If you do not hear
“tap”, AutoPrime is damaged. Take
sprayer to Graco/MAGNUM autho-
rized service center.
Inlet valve check ball or seat is dirty. Remove inlet fitting. Clean or
replace ball and seat.
Outlet valve check ball is stuck. ProLTS 17 and ProLTS 19: Insert
screw driver in slot and remove
Easy-Access door, page 8.
Unscrew outlet valve with a 3/4 in.
socket. Remove and clean assem-
bly.
LTS 15 and LTS 17: Remove outlet
fitting and clean outlet check ball.
Suction tube is leaking, allowing air
to enter.
Check suction tube for cracks and
cuts. Make sure suction tube clamp
is on hose. Replace suction tube if
cracked or damaged.
Pump valves are worn. Check for worn pump valves.
a. Prime sprayer with paint
b. Trigger gun momentarily.
When trigger is released,
pump should cycle momen-
tarily and stop. If pump con-
tinues to cycle, pump valves
may be worn.
Paint is very thick or tacky. Thin material per manufacturer
recommendations.
Momentarily turn power switch OFF
to allow pump to slow and stop.
Repeat as necessary.
Problem Cause Solution

Basic Troubleshooting
313036N 15
Pump cycles but does not build up
pressure.
Prime/Spray valve in PRIME posi-
tion (pointing down).
Turn Prime/Spray valve to SPRAY
position (pointing forward).
Pump is not primed. Prime pump, see Operation manual
313034.
Inlet screen is clogged or suction
tube is not immersed.
Clean debris off inlet screen and
make sure suction tube is immersed
in fluid.
Suction tube is leaking, allowing air
to enter.
Check suction tube for cracks and
cuts. Make sure suction tube clamp
is on hose. Replace suction tube if
cracked or damaged.
Prime/Spray Valve is worn or
obstructed with debris.
Take sprayer to Graco/MAGNUM
authorized service center.
Pump check ball is stuck. Read Pump does not prime sec-
tion in Troubleshooting, page 14.
Pump cycles, but paint only dribbles
or spurts when spray gun is trig-
gered.
Pressure is set too low. Slowly turn pressure control knob
clockwise to increase pressure set-
ting which will turn motor on to build
pressure.
Spray tip is clogged. Unclog spray tip, see Operation
manual 313034.
InstaClean fluid filter is clogged.
(ProLTS 17 and ProLTS 19 Only)
Clean or replace InstaClean fluid fil-
ter, see Operation manual 313034.
Spray gun fluid filter is clogged. Clean or replace gun fluid filter, see
Operation manual 313034.
Spray tip is too large or worn. Replace tip.
Problem Cause Solution

Basic Troubleshooting
16 313036N
Pressure is set at maximum but
cannot achieve a good spray pattern.
Spray tip is clogged. Unclog spray tip, see Operation
manual 313034.
Reversible spray tip is in UNCLOG
position.
Rotate arrow-shaped handle on
spray tip so it points forward on gun.
Spray tip is too large for sprayer. Select smaller spray tip.
Spray tip is worn beyond capability of
sprayer.
Replace spray tip.
Extension cord is too long or not
heavy enough gauge.
Replace extension cord. See
Grounding and Electrical
Requirements, page 10.
Spray gun fluid filter is clogged. Clean or replace spray gun fluid filter,
see Operation manual 313034.
InstaClean fluid filter is clogged.
(ProLTS 17 and ProLTS 19 Only)
Clean or replace InstaClean fluid
filter, see Operation manual 313034.
Inlet screen is clogged. Clean debris off inlet screen.
Pump valves are worn. Check for worn pump valves.
a. Prime sprayer with paint
b. Trigger gun momentarily.
When trigger is released,
pump should cycle momen-
tarily and stop. If pump con-
tinues to cycle, pump valves
may be worn.
Material is too thick. Thin material.
Hose is too long (if extra section is
added).
Remove extra section of hose.
Spray gun stopped spraying. Pump
is not cycling.
Spray tip is clogged. Unclog spray tip, see Operation
manual 313034.
When paint is sprayed, it runs down
the wall or sags.
Coat is going on too thick. Move gun faster.
Choose a tip with smaller hole size.
Choose tip with wider fan.
Make sure gun is far enough from
surface.
When paint is sprayed, coverage is
inadequate.
Coat is going on too thin. Move gun slower.
Choose tip with larger hole size.
Choose tip with narrower fan.
Make sure gun is close enough to
surface.
Fan pattern varies dramatically while
spraying.
OR
Sprayer does not turn on promptly
when resuming spraying.
Pressure control switch is worn and
causing excessive pressure
variation.
Take sprayer to Graco/MAGNUM
authorized service center.
Cannot trigger spray gun. Spray gun trigger lock is locked. Rotate trigger safety lever to unlock
trigger lock, page 11.
Paint is coming out of pressure
control switch.
Pressure control switch is worn. Take sprayer to Graco/MAGNUM
authorized service center.
Problem Cause Solution

Basic Troubleshooting
313036N 17
Prime/Spray valve actuates
automatically relieving pressure
through prime tube.
System is over pressurizing. Take sprayer to Graco/MAGNUM
authorized service center.
Paint leaks down outside of pump. Pump packings are worn. Take sprayer to Graco/MAGNUM
authorized service center.
Motor is hot and runs intermittently.
Motor automatically shuts off due to
excessive heat. Damage can occur if
cause is not corrected. See Thermal
Overload, page 10.
Vent holes in enclosure are plugged
or sprayer is covered.
Keep vent holes clear of obstructions
and overspray and keep sprayer
open to air.
Extension cord is too long or not a
heavy enough gauge.
Replace extension cord. Read
Grounding and Electrical
Requirements, page 10.
Unregulated electrical generator
being used has excessive voltage.
Use electrical generator with a proper
voltage regulator. Sprayer requires
120VAC, 60 Hz, 1500-Watt
generator.
Problem Cause Solution

Advanced Troubleshooting
18 313036N
Advanced Troubleshooting
See Basic Troubleshooting first, page 13 for problems that are more easily remedied.
General Problem: Motor Does Not Operate
Specific Problem Cause Solution
Power switch is on and
sprayer is plugged in; pump
does not cycle.
See Basic Troubleshoot-
ing, page 13.
Basic mechanical problems. Paint is frozen or hardened in
pump.
Unplug sprayer from electrical outlet.
If paint is frozen in sprayer:
Do NOT try to start sprayer until completely
thawed or you may damage the motor, control
board, and/or drivetrain.
1. Turn power switch OFF.
2. Place sprayer in warm area for several hours.
3. Plug sprayer in.
4. Turn power switch ON and flush sprayer with
water or mineral spirits.
a. Turn on sprayer.
b. Turn prime valve to PRIME position.
If paint hardened in sprayer:
ProLTS 17 and ProLTS 19: Replace pump
packings. See List of Kits, page 28.
LTS 15 and LTS 17: Replace complete pump.
See List of Kits, page 28.
Remove all residue from inlet and outlet valves.
Gears are damaged. Remove motor enclosure and rotate motor fan to
check for bad gears. If gears bind or slip, remove
pump cover and replace failed gears. See List
of Kits, page 28.
ProLTS 17 and ProLTS 19:
Yoke is broken because
pump is locked up due to
dried paint or worn packings.
Repair or replace using Gear/Yoke Kit. See List
of Kits, page 28.
Replace pump packings on ProLTS 17 and Pro-
LTS 19 sprayers. See List of Kits, page 28.

Advanced Troubleshooting
313036N 19
Basic electrical problems. Motor overheated. Allow motor to cool for 45 minutes. Retry.
Electrical outlet is damaged. Reset building circuit breaker or replace fuse.
Try another outlet.
Check electric supply with volt meter. Meter must
read 85 to 130V AC. If voltage is too high, do not
plug sprayer in until outlet is corrected.
Control board leads are
improperly fastened, improp-
erly mated, or
corroded.
Replace any loose terminals. Make sure all leads
and harnesses are firmly connected.
ProLTS 17 and ProLTS 19: Check pressure
control harness connection on front side of drive
housing.
Clean control board terminals. Securely recon-
nect leads.
Motor brushes are worn. Check length of BOTH brushes (brushes do not
wear evenly on both sides of the motor). Brush
length must be 0.25 in. (6.4mm). If brushes are
worn replace motor using Motor Kit, page 28.
Motor armature commutator
damaged.
Check for burn spots, gouges and extreme
roughness. If damaged or if shorts are evident,
replace motor using Motor Kit, page 28.
Fuse is blown. Find cause for blown fuse before replacing. Turn
the motor fan to check for a locked gear or
pump. Use a continuity meter to check for a short
to ground caused by a pinched wire.
ProLTS 17 and ProLTS 19: Replace the fuse
with correct fuse kit. See List of Kits, page 28.
LTS 15 and LTS 17: The fuse is not replaceable.
Replace control board. See List of Kits, page
28.
Motor armature shorting. Check for shorts. See Motor Diagnostics, page
25. If shorts are evident, replace motor using
Motor Kit, page 28.
Motor armature open circuit. Check motor leads for continuity. If open circuit,
check brushes. Use Motor Kit to replace motor.
See List of Kits, page 28.
Control board damaged.
CAUTION: Do not perform
control board diagnostics until
you have determined the
armature is good. A damaged
armature can burn out a good
control board.
See Control Board Diagnostics, page 27.
Replace control board if damaged using Control
Board Kit, page 28.
Specific Problem Cause Solution

Advanced Troubleshooting
20 313036N
Sprayer Wiring Problems
NOTE: Remove enclosure
mounting screws and pull
enclosure away from drive
housing. Take care not to pull
on leads from electrical cord
and power switch.
Sprayer power cord dam-
aged.
Unplug sprayer power cord.
Disconnect black power cord wire at power
switch.
Unplug in-line connection white cord wire.
Plug in power cord.
Test voltage between black and white wires of
power cord. Meter must read 85 to 130V AC.
Replace power cord if no voltage.
Sprayer power switch dam-
aged.
1. Unplug sprayer power cord.
2. Disconnect black control board wire at power
switch.
3. Unplug in-line connection white cord wire.
4. Plug in power cord.
5. Turn power switch ON.
6. Test voltage between open terminal of power
switch and white power cord wire. Meter must
read 85 to 130V AC.
7. Replace power switch if no voltage.
Motor thermal overload cutoff
switch.
WARNING: See Startup
Hazard After Thermal Over-
load on page 10.
1. Unplug sprayer power cord.
2. Remove motor harness from control card.
3. Check for continuity between yellow leads or
motor harness (Pro LTS 19 only).
4. If thermal relief switch is open (no continuity)
allow motor to cool.
5. If switch remains open after motor cools,
replace motor using Motor Kit, page 28.
6. If thermal relief switch closes after motor
cools, find correct cause of overheating.
Specific Problem Cause Solution