0103 © 2003 SprayTECH. All rights reserved. Form No. 0509811A
Printed in the U. S. A.
GPX 750
Gas Piston Pump
Owner’s Manual
Model Number 0509004
SprayTECH
1770 Fernbrook Lane
Minneapolis, MN 55447
Technical Assistance: 1-800-292-4637
Order Entry: 1-800-443-4500
Fax: 1-800-525-9501
www.spraytechinc.com
Table of Contents
Safety Precautions.................................................................2
Français ..............................................................................18
Español...............................................................................20
General Description ...............................................................4
Operation ................................................................................4
Setup ....................................................................................4
Preparing to Paint.................................................................4
Painting.................................................................................5
Pressure Relief Procedure ...................................................6
Spraying ..................................................................................6
Spraying Technique ..............................................................6
Practice.................................................................................6
Cleanup ...................................................................................7
Maintenance............................................................................7
General Repair and Service Notes.......................................7
Maintaining the Engine .........................................................8
Replacing the Filter...............................................................8
Replacing the PRIME/SPRAY Valve.....................................8
Replacing the Potentiometer ................................................9
Replacing the Pump ON/OFF Switch...................................9
Replacing the Gears and/or Slider Assembly.....................10
Replacing the Electronic Pressure Control (EPC) Board ...11
Replacing the Transducer...................................................11
Servicing the Clutch Assembly...........................................12
Servicing the Fluid Section.................................................14
Troubleshooting ...................................................................16
Parts Listings........................................................................22
Main Assembly....................................................................22
Drive Assembly...................................................................23
Fluid Section Assembly ......................................................24
Cart Assembly.....................................................................25
Filter Assembly ...................................................................25
PRIME/SPRAY Assembly ...................................................26
Electrical Schematic ...........................................................26
Labels .................................................................................26
Accessories ........................................................................27
Limited Warranty..................................................................28
Safety Precautions
This manual contains information that must be read and
understood before using the equipment. When you come to an
area that has one of the following symbols, pay particular
attention and make certain to heed the safeguard.
This symbol indicates a potential hazard that may cause
serious injury or loss of life. Important safety information will
follow.
This symbol indicates a potential hazard to you or to the
equipment. Important information that tells how to prevent
damage to the equipment or how to avoid causes of minor
injuries will follow.
HAZARD: Injection injury - A high pressure stream
produced by this equipment can pierce the
skin and underlying tissues, leading to serious
injury and possible amputation. See a
physician immediately.
DO NOT TREAT AN INJECTION INJURY AS A SIMPLE
CUT! Injection can lead to amputation. See a physician
immediately.
The maximum operating range of the gun is 3300 PSI /
228BAR fluid pressure.
NOTE: Notes give important information which should
be given special attention.
2©SprayTECH. All rights reserved.
PREVENTION:
• NEVER aim the gun at any part of the body.
•NEVER allow any part of the body to touch the fluid stream.
DO NOT allow body to touch a leak in the fluid hose.
• NEVER put your hand in front of the gun. Gloves will not
provide protection against an injection injury.
•ALWAYS lock the gun trigger, shut the pump off, and release
all pressure before servicing, cleaning the tip or guard,
changing tip, or leaving unattended. Pressure will not be
released by turning off the motor. The PRIME/SPRAY knob
must be turned to PRIME to relieve the pressure. Refer to
the PRESSURE RELIEF PRESSURE described in the pump
manual.
•ALWAYS keep the tip guard in place while spraying. The
tip guard provides some protection but is mainly a warning
device.
•ALWAYS remove the spray tip before flushing or cleaning
the system.
• The paint hose can develop leaks from wear, kinking and
abuse. A leak can inject material into the skin. Inspect
the hose before each use.
•NEVER use a spray gun without a trigger lock and trigger
guard in place and in good working order.
• All accessories must be rated at or above 3300 PSI / 228
BAR. This includes spray tips, guns, extensions, and
hose.
HAZARD: EXPLOSION OR FIRE - Solvent and paint fumes
can explode or ignite. Severe injury and/or
property damage can occur.
PREVENTION:
• Provide extensive exhaust and fresh air introduction to
keep the air within the spray area free from accumulation
of flammable vapors.
•Avoid all ignition sources such as static electric sparks,
open flames, pilot lights, and hot objects. Connecting or
disconnecting power cords or working light switches can
make sparks.
•Do not smoke in spray area.
• Fire extinguisher must be present and in good working
order.
• Place paint pump in a well ventilated area. Flammable
vapors are often heavier than air. Floor area must be
extremely well ventilated. The paint pump contains arcing
parts that emit spark and can ignite vapors.
• The equipment and objects in and around the spray area
must be properly grounded to prevent static sparks.
• Use only conductive or grounded high pressure fluid hose.
Gun must be grounded through hose connections.
• Power cord must be connected to a grounded circuit
(electric models only).
• Always flush unit into a separate metal container, at low
pump pressure, with spray tip removed. Hold gun firmly
against side of container to ground container and prevent
static sparks.
• Follow the material and solvent manufacturer's warnings
and instructions.
• Use extreme caution when using materials with a
flashpoint below 70° F (21° C). Flashpoint is the
temperature that a fluid can produce enough vapors to
ignite.
• Plastic can cause static sparks. Never hang plastic to
enclose a spray area. Do not use plastic drop cloths
when spraying flammable materials.
• Use lowest possible pressure to flush equipment.
NOTE TO PHYSICIAN:
Injection into the skin is a traumatic injury. It is
important to treat the injury as soon as possible. DO
NOT delay treatment to research toxicity. Toxicity is a
concern with some coatings injected directly into the
blood stream. Consultation with a plastic surgeon or
reconstructive hand surgeon may be advisable.
WARNING
GAS ENGINE (WHERE APPLICABLE)
Always place pump outside of structure in fresh air. Keep all
solvents away from the engine exhaust. Never fill fuel tank
with a running or hot engine. Hot surface can ignite spilled
fuel. Always attach ground wire from pump unit to a grounded
object, such as a metal water pipe. Refer to engine owner’s
manual for complete safety information.
HAZARD: EXPLOSION HAZARD DUE TO INCOMPATIBLE
MATERIALS - Will cause severe injury or
property damage.
PREVENTION:
• Do not use materials containing bleach or chlorine.
• Do not use halogenated hydrocarbon solvents such as
mildewcide, methylene chloride and 1,1,1 trichloroethane. They are not compatible with aluminum.
• Contact your coating supplier about the compatibility of
material with aluminum.
HAZARD: HAZARDOUS VAPORS - Paints, solvents,
insecticides, and other materials can be
harmful if inhaled or come in contact with the
body. Vapors can cause severe nausea,
fainting, or poisoning.
PREVENTION:
• Use a respirator or mask if vapors can be inhaled. Read
all instructions supplied with the mask to be sure it will
provide the necessary protection.
•Wear protective eyewear.
•Wear protective clothing as required by coating
manufacturer.
HAZARD: GENERAL - This product can cause severe
injury or property damage.
PREVENTION:
• Read all instructions and safety precautions before
operating equipment.
• Always disconnect the motor from the power supply
before working on the equipment (electric models only).
• Follow all appropriate local, state, and national codes
governing ventilation, fire prevention, and operation.
• The United States Government Safety Standards have
been adopted under the Occupational Safety and Health
Act (OSHA). These standards, particularly part 1910 of
the General Standards and part 1926 of the Construction
Standards should be consulted.
• Use only manufacturer authorized parts. User assumes
all risks and liabilities when using parts that do not meet
the minimum specifications and safety devices of the
pump manufacturer.
• Before each use, check all hoses for cuts, leaks, abrasion
or bulging of cover. Check for damage or movement of
couplings. Immediately replace the hose if any of these
conditions exist. Never repair a paint hose. Replace it
with another grounded high-pressure hose.
• All hoses, swivels, guns, and accessories must be rated at
or above 3300PSI/228 BAR.
• Do not spray outdoors on windy days.
•Wear clothing to keep paint off skin and hair.
• Always unplug cord from outlet before working on
equipment.
• Do not use this equipment to spray water or acid.
Do not lift by cart handle when loading or unloading.
Gasoline Engine Safety
The engine exhaust from this unit contains chemicals
known to the State of California to cause cancer, birth
defects, or other reproductive harm.
1. Gas engines are designed to give safe and dependable
service if operated according to instructions. Read and
understand the engine Owner's Manual before operating
the engine. Failure to do so could result in personal injury
or equipment damage.
2. To prevent fire hazards and to provide adequate
ventilation, keep the engine at least 1 meter (3 feet) away
from buildings and other equipment during operation. Do
not place flammable objects close to the engine.
3. Children and pets must be kept away from the area of
operation due to a possibility of burns from hot engine
components or injury from any equipment the engine may
be used to operate.
4. Know how to stop the engine quickly, and understand the
operation of all controls. Never permit anyone to operate
the engine without proper instructions.
5. Gasoline is extremely flammable and is explosive under
certain conditions.
6. Refuel in a well-ventilated area with the engine stopped.
Do not smoke or allow flames or sparks in the refueling
area or where gasoline is stored.
7. Do not overfill the fuel tank. After refueling, make sure the
tank cap is closed properly and securely.
8. Be careful not to spill fuel when refueling. Fuel vapor or
spilled fuel may ignite. If any fuel is spilled, make sure the
area is dry before starting the engine.
9. Never run the engine in an enclosed or confined area.
Exhaust contains poisonous carbon monoxide gas;
exposure may cause loss of consciousness and may lead
to death.
10. The muffler becomes very hot during operation and
remains hot for a while after stopping the engine. Be
careful not to touch the muffler while it is hot. To avoid
severe burns or fire hazards, let the engine cool before
transporting it or storing it indoors.
11. Never ship/transport unit with gasoline in the tank.
© SprayTECH. All rights reserved. 3
General Description
This airless sprayer is a precision power tool used for spraying
many types of materials. Read and follow this instruction
manual carefully for proper operating instructions,
maintenance, and safety information.
Operation
This equipment produces a fluid stream at extremely high
pressure. Read and understand the warnings in the
Safety Precautions section at the front of this manual
before operating this equipment.
Setup
Perform the following procedure before starting the engine of a
gas-powered sprayer.
1. Ensure that the siphon tube and the return hose are
attached and secure.
2. Attach the supplied grounding cable to a grounded object.
3. Using a wrench, attach a minimum of 50’ of 1/4” nylon
airless spray hose to the outlet fitting on the sprayer.
Tighten securely.
4. Attach an airless spray gun to the spray hose. Using two
wrenches (one on the gun and one on the hose), tighten
securely.
Make sure all airless hoses and spray guns are electrically
grounded and rated for at least 3300 psi (228 bar) fluid
pressure.
5. Turn the pressure control knob fully counterclockwise to
its lowest pressure setting.
6. Make sure the pump ON/OFF switch is in the OFF position.
7. Fill the fluid section oil cup with approximately one
tablespoon of separating oil (P/N 0279920).
Never operate unit for more than ten seconds without
fluid. Operating this unit without fluid will cause
unnecessary wear to the packings.
8. Check the engine oil level. The gasoline engine oil level
is determined by the manufacturer. Refer to the engine
manufacturer's service manual (supplied).
9. Close the fuel shut-off lever and fill the gas tank with
gasoline. Use only high quality, unleaded gasoline.
NOTE: Do not attach the tip to the spray gun yet.
Remove the tip if it is already attached.
4©SprayTECH. All rights reserved.
Preparing a New Sprayer
If this unit is new, it is shipped with test fluid in the fluid section
to prevent corrosion during shipment and storage. This fluid
must be thoroughly cleaned out of the system with mineral
spirits before you begin spraying.
Always keep the trigger lock on the spray gun in the
locked position while preparing the system.
1. Place the siphon tube into a container of mineral spirits
that has a flash point of 60ºC (140ºF) or above.
2. Place the return hose into a metal waste container.
3. Turn the pressure control knob fully counterclockwise to
its lowest pressure setting.
4. Move the PRIME/SPRAY valve to the PRIME position.
5. Move the engine ON/OFF switch to the ON position.
6. Start the engine:
a. Open the fuel valve
lever.
b. Move the throttle
lever away from the
gas tank.
c. Close the engine
choke lever.
d. Holding the frame
with one hand, pull
the starter rope
rapidly and firmly. Continue to hold the rope as you let
it return. Pull and return the rope until the engine
starts.
7. Turn on the sprayer by moving
the pump ON/OFF switch to the
ON position.
8. Slowly turn the pressure control
knob clockwise to increase the
pressure until fluid starts to
come out of the return hose.
Use only enough pressure to
keep the fluid coming out.
9. Allow the sprayer to run for
15–30 seconds to flush the test fluid out through the
return hose and into the waste container.
10. Turn the pressure control knob fully counterclockwise to
its lowest setting.
11.Turn off the sprayer by moving the pump ON/OFF switch
to the OFF position.
Preparing to Paint
Before painting, it is important to make sure that the fluid in the
system is compatible with the paint that is going to be used.
Always keep the trigger lock on the spray gun in the
locked position while preparing the system.
1. Place the siphon tube into a container of the appropriate
solvent for the material being sprayed (refer to
recommendations of the material manufacturer). An
example of the appropriate solvent is water for latex paint.
2. Place the return hose into a metal waste container.
3. Turn the pressure control knob fully counterclockwise to
its lowest pressure setting.
4. Move the PRIME/SPRAY valve to the PRIME position.
5. Move the engine ON/OFF switch to the ON position.
NOTE: Incompatible fluids and paint may cause the
valves to become stuck closed, which would
require disassembly and cleaning of the
sprayer’s fluid section.
Pressure
Control
Knob
Pump
ON/OFF
Switch
Fuel Valve
Lever
Choke Lever
Engine
ON/OFF
Switch
Throttle
Lever
Starter Rope
Engine
Pressure Control
Knob
Pail Hook
Fluid Section
Siphon Tube
PRIME/SPRAY
Val ve
Outlet Fitting
Cart
Filter
Assembly
6. Start the engine:
a. Open the fuel valve lever.
b. Move the throttle lever away from the gas tank.
c. Close the engine choke lever.
d. Holding the frame with one hand, pull the starter rope
rapidly and firmly. Continue to hold the rope as you let
it return. Pull and return the rope until the engine
starts.
7. Turn on the sprayer by moving the pump ON/OFF switch
to the ON position.
8. Slowly turn the pressure control knob clockwise to
increase the pressure until fluid starts to come out of the
return hose. Use only enough pressure to keep the fluid
coming out.
9. Allow the sprayer to run for 15–30 seconds to flush the old
solvent out through the return hose and into the metal
waste container.
10. Turn the pressure control knob fully counterclockwise to
its lowest setting.
11.Turn off the sprayer by moving the pump ON/OFF switch
to the OFF position.
12. Move the PRIME/SPRAY valve to the SPRAY position.
13. Turn on the sprayer.
14. Turn the pressure control knob slowly clockwise to
increase pressure.
15. Unlock the gun by turning the gun trigger lock to the
unlocked position.
Ground the gun by holding it against the
edge of the metal container while
flushing. Failure to do so may lead to a
static electric discharge, which may
cause a fire.
16. Trigger the gun into the metal waste
container until the old solvent is gone
and fresh solvent is coming out of the gun.
17. Lock the gun by turning the gun trigger lock to the locked
position.
18. Set down the gun and increase the pressure by turning
the pressure control knob slowly clockwise to its highest
setting.
19. Check the entire system for leaks. If leaks occur, turn the
sprayer off and follow the “Pressure Relief Procedure” in
this manual before tightening any fittings or hoses.
20. Follow the “Pressure Relief Procedure” in this manual
before changing from solvent to paint.
Be sure to follow the pressure relief procedure when
shutting the unit down for any purpose, including
servicing or adjusting any part of the spray system,
changing or cleaning spray tips, or preparing for cleanup.
Painting
1. Place the siphon tube into a container of paint.
2. Place the return hose into a metal waste container.
3. Turn the pressure control knob fully counterclockwise to
its lowest pressure setting.
4. Move the PRIME/SPRAY valve to the PRIME position.
5. Move the engine ON/OFF switch to the ON position.
6. Start the engine:
a. Open the fuel valve lever.
b. Move the throttle lever away from the gas tank.
NOTE: Make sure that the spray gun does not have a
tip or tip guard installed.
c. Close the engine
choke lever.
d. Holding the frame
with one hand, pull
the starter rope
rapidly and firmly.
Continue to hold
the rope as you let
it return. Pull and
return the rope until
the engine starts.
7. Turn on the sprayer
by moving the pump ON/OFF switch to the ON position.
8. Slowly turn the pressure control
knob clockwise to increase the
pressure until fluid starts to
come out of the return hose.
Use only enough pressure to
keep the fluid coming out.
9. Allow the sprayer to run until
paint is coming through the
return hose into the metal
waste container.
10. Turn the pressure control knob fully counterclockwise to
its lowest setting.
11.Turn off the sprayer by moving the pump ON/OFF switch
to the OFF position.
12. Remove the return hose from the waste container and place
it in its operating position above the container of paint.
13. Move the PRIME/SPRAY valve to the SPRAY position.
14. Turn on the sprayer.
15. Turn the pressure control knob slowly clockwise to
increase pressure.
16. Unlock the gun by turning the gun trigger lock to the
unlocked position.
Ground the gun by holding it against the
edge of the metal container while
flushing. Failure to do so may lead to a
static electric discharge, which may
cause a fire.
17. Trigger the gun into the metal waste
container until all air and solvent is flushed from the spray
hose and paint is flowing freely from the gun.
18. Lock the gun by turning the gun trigger lock to the locked
position.
19. Turn the pressure control knob fully counterclockwise to
its lowest setting.
20. Turn off the sprayer.
21. Attach tip guard and tip to the gun as instructed by the tip
guard or tip manuals.
POSSIBLE INJECTION HAZARD. Do not spray without the
tip guard in place. Never trigger the gun unless the tip is in
either the spray or the unclog position. Always engage the
gun trigger lock before removing, replacing or cleaning tip.
22. Turn on the sprayer.
23. Increase the pressure by turning the pressure control
knob slowly clockwise and test the spray pattern on a
piece of cardboard. Adjust the pressure control knob until
the spray from the gun is completely atomized. Try to
keep the pressure control knob at the lowest setting that
maintains good atomization.
NOTE: Turning the pressure up higher than needed to
atomize the paint will cause premature tip wear
and additional overspray.
Pressure
Control
Knob
Pump
ON/OFF
Switch
Fuel Valve
Lever
Choke Lever
Engine
ON/OFF
Switch
Throttle
Lever
Starter Rope
© SprayTECH. All rights reserved. 5
Pressure Relief Procedure
Be sure to follow the pressure relief procedure when
shutting the unit down for any purpose, including
servicing or adjusting any part of the spray system,
changing or cleaning spray tips, or preparing for cleanup.
1. Lock the gun by turning the gun trigger lock to the locked
position.
2. Turn off the sprayer by moving the pump ON/OFF switch
to the OFF position.
3. Turn off the engine by moving the engine ON/OFF switch
to the OFF position.
4. Turn the pressure control knob counterclockwise to its
lowest setting.
5. Unlock the gun by turning the gun trigger lock to the
unlocked position.
4. Hold the metal part of the gun firmly to
the side of a metal container to ground
the gun and avoid a build up of static
electricity.
5. Trigger the gun to remove any pressure
that may still be in the hose.
6. Lock the gun by turning the gun trigger lock to the locked
position.
7. Move the PRIME/SPRAY valve to the PRIME position.
Spraying
Spraying Technique
The key to a good paint job is an even coating over the entire
surface. This is done by using even strokes. Keep your arm
moving at a constant speed and keep the spray gun at a
constant distance from the surface. The best spraying distance
is 10 to 12 inches between the spray tip and the surface.
Keep the spray gun at right angles to the surface. This means
moving your entire arm back and forth rather than just flexing
your wrist.
Heavy Coat
Do not flex wrist while spraying.
Light Coat Light Coat
Keep stroke smooth and at an even speed.
Even coat throughout
Approximately
10 to 12 inches
NOTE: When spraying block filler, mastics or high
solid coating, remove the gun filter and high
pressure filter screens.
6©SprayTECH. All rights reserved.
Keep the spray gun perpendicular to the surface, otherwise
one end of the pattern will be thicker than the other.
The spray gun should be triggered by turning it on and off with
each stroke. This will save paint and avoid paint buildup at the
end of the stroke. Do not trigger the gun during the middle of
a stroke. This will result in an uneven spray and splotchy
coverage.
Overlap each stroke by about 30%. This will ensure an even
coating.
When you stop painting, lock the gun trigger lock, turn the
pressure control knob counterclockwise to its lowest setting
and set the PRIME/SPRAY valve to PRIME. Turn the motor
switch to OFF and unplug the sprayer.
Practice
1. Be sure that the paint hose is free of kinks and clear of
objects with sharp cutting edges.
2. Turn the pressure control knob counterclockwise to its to
its lowest setting.
3. Move the PRIME/SPRAY valve to the SPRAY position.
4. Turn the pressure control knob clockwise to its highest
setting. The paint hose should stiffen as paint begins to
flow through it.
5. Unlock the gun trigger lock.
6. Trigger the spray gun to bleed air out of the hose.
7. When paint reaches the spray tip, spray a test area to
check the spray pattern.
8. Use the lowest pressure
setting necessary to get a
good spray pattern. If the
pressure is set too high, the
spray pattern will be too light.
If the pressure is set too low,
tailing will appear or the paint
will spatter out in gobs rather
than in a fine spray.
Approximately
10 to 12 inches
Right way
Wrong way
Proper way to trigger the spray gun
Keep stroke
even
Approximately
10 to 12 inches
Start stroke End strokePull trigger Release triggerKeep steady
Good spray pattern
Paint tailing pattern
Cleanup
Special cleanup instructions for use with flammable
solvents:
•Always flush spray gun preferably outside and at least one
hose length from spray pump.
• If collecting flushed solvents in a one gallon metal
container, place it into an empty five gallon container, then
flush solvents.
• Area must be free of flammable vapors.
• Follow all cleanup instructions.
The sprayer, hose, and gun should be cleaned thoroughly
after daily use. Failure to do so permits material to build
up, seriously affecting the performance of the unit.
Always spray at minimum pressure with the gun nozzle tip
removed when using mineral spirits or any other solvent
to clean the sprayer, hose, or gun. Static electricity
buildup may result in a fire or explosion in the presence of
flammable vapors.
1. Follow the “Pressure Relief Procedure” found in the
Operation section of this manual.
2. Remove the gun tip and tip guard and clean with a brush
using the appropriate solvent.
3. Place the siphon tube into a container of the appropriate
solvent (refer to recommendations of the material
manufacturer). An example of the appropriate solvent is
water for latex paint.
4. Place the return hose into a metal waste container.
5. Move the PRIME/SPRAY valve to its PRIME position.
6. Move the engine ON/OFF switch to the ON position and
start the engine.
7. Turn on the sprayer by moving the pump ON/OFF switch
to the ON position.
8. Slowly turn the pressure control knob clockwise to increase
the pressure until fluid starts to come out of the return hose.
9. Allow the solvent to circulate through the sprayer and
flush the paint out of the return hose into the metal waste
container.
10. Turn the pressure control knob fully counterclockwise to
its lowest setting.
11.Turn off the sprayer by moving the ON/OFF switch to the
OFF position.
12. Move the PRIME/SPRAY valve to its SPRAY position.
13. Turn on the sprayer.
14. Turn the pressure control knob slowly clockwise to
increase pressure.
Ground the gun by holding it against the
edge of the metal container while
flushing. Failure to do so may lead to a
static electric discharge, which may cause
a fire.
15. Trigger the gun into the metal waste
container until the paint is flushed out of the hose and
solvent is coming out of the gun.
16. Continue to trigger the spray gun into the waste container
until the solvent coming out of the gun is clean.
NOTE: For long-term or cold weather storage, pump
mineral sprits through the entire system.
© SprayTECH. All rights reserved. 7
17. Follow the “Pressure Relief Procedure” found in the
Operation section of this manual.
18. Store the sprayer in a clean, dry area.
Do not store the sprayer under pressure.
Cleaning the Spray Tip
1. Flush the gun with solvent immediately after the work is
completed.
2. Oil the sliding pins to prevent them from seizing up.
Should the spray tip become clogged, reverse
the spray tip with the lever and pull the trigger.
Once the obstruction comes out of the spray tip,
release the trigger, reverse the spray tip back to
the spray pattern setting, and resume spraying.
Do not attempt to clean the tip with your finger.
Do not use a needle or other sharp pointed instrument to
clean the tip. The hard tungsten carbide is brittle and can
be chipped.
Maintenance
Before proceeding, follow the Pressure Relief Procedure
outlined previously in this manual. Additionally, follow all
other warnings to reduce the risk of an injection injury,
injury from moving parts, or electric shock.
General Repair and Service Notes
The following tools are needed when repairing this sprayer:
Phillips screwdriver 3/8" hex wrench
needle-nose pliers 5/16" hex wrench
adjustable wrench 1/4" hex wrench
rubber mallet 3/16" hex wrench
flat-blade screwdriver 1/8” hex wrench
1/2” open-end wrench 7/8” open-end wrench
1. Before repairing any part of the sprayer, read the
instructions carefully, including all warnings.
Never pull on a wire to disconnect it. Pulling on a wire
could loosen the connector from the wire.
2. Test your repair before regular operation of the sprayer to
be sure that the problem is corrected. If the sprayer does
not operate properly, review the repair procedure to
determine if everything was done correctly. Refer to the
Troubleshooting section to help identify other possible
problems.
3. Make certain that the service area is well ventilated in
case solvents are used during cleaning. Always wear
protective eyewear while servicing. Additional protective
equipment may be required depending on the type of
cleaning solvent. Always contact the supplier of solvents
for recommendations.
4. If you have any further questions concerning your
SprayTECH airless sprayer, call SprayTECH:
Technical Service...................................1-800-292-4637
Fax ................................................1-800-525-9501
NOTE: All Honda engine work should be performed by
a Honda authorized service center.
Maintaining the Engine
When transporting a sprayer with a gas engine, make sure
the fuel is shut off.
Important Facts Concerning this Sprayer
This gas-powered sprayer contains a clutch that engages
when the sprayer is pumping. The sprayer’s pressure control
system engages and disengages the clutch to control
pressure. To prevent unnecessary wear to the clutch, it is
advisable to adjust the engine speed and pressure setting to
limit the amount of times the clutch engages and disengages.
To reduce clutch wear, refer to the following examples.
Example:
Operating one gun with a .019 tip — reduce the engine speed
by adjusting the throttle to a low or medium setting and
increase pressure only until the heavy ends of the spray
pattern have been eliminated.
Example:
Operating one gun with .023 tip — increase engine speed to a
high setting and increase pressure until the heavy ends of the
spray pattern have been eliminated.
Example:
Spraying light-bodied materials at low pressure — to reduce
surging at the gun and to decrease clutch wear, reduce the
engine speed to idle and reduce pressure until the desired
spray pattern is achieved.
Routine Engine Maintenance
Daily
• Check and fill the gas tank.
• After the first 20 hours of operation, drain the oil and refill
with clean oil. Check the engine oil level and fill as
necessary.
Weekly
• Remove the cover of the air filter and clean the element.
Replace the element if necessary. If operating in an
unusually dusty environment, check the filter daily and
replace if necessary. (Replacement elements can be
purchased from your local SprayTECH dealer.)
• After each 50 hours of operation: Change the engine oil.
Spark Plug
• Use only a (NKG) BP6ES plug.
• Gap the plug 0.025” – 0.030” (0.7 – 0.8 mm).
• Make sure to use a spark plug wrench when installing and
removing the plug.
NOTE: For detailed engine specifications and
maintenance, refer to the separate engine
manual supplied with this sprayer.
8©SprayTECH. All rights reserved.
Replacing the Filter
1. Loosen and remove the filter
body by hand.
2. Remove the filter and core
spring from the filter housing.
3. Remove the core spring from
inside the filter.
4. Inspect the filter. Based on
inspection, clean or replace the
filter.
5. Inspect the filter housing o-ring.
Based on inspection, clean or
replace the o-ring.
6. Slide the new or cleaned filter
over the core spring. Place the
filter and core spring into the
center of the filter housing.
7. Clean the inside of the filter
body.
8. Slide the filter body over the
filter and thread it into the filter
housing until secure.
Replacing the PRIME/SPRAY Valve
Perform the following procedure using PRIME/SPRAY valve
replacement kit P/N 0507690.
1. Drive the groove pin out of the valve handle.
2. Remove the valve handle and the cam base.
3. Using a wrench, loosen and remove the valve housing
assembly.
4. Make sure the gasket is in place and thread the new valve
housing assembly into the filter housing. Tighten securely
with a wrench.
5. Place the cam base over the valve housing assembly.
Lubricate the cam base with grease and line up the cam
with the filter block using the dowel pin.
6. Line up the hole on the valve stem with the hole in the
valve handle.
7. Insert the groove pin into the valve handle and through
the valve stem to secure the valve handle in position.
Dowel Pin
Cam Base
Valve Stem
Filter
Housing
Valve Housing
Assembly
Gasket
Valve Handle
Groove Pin
NOTE: The filter body should
be hand-tightened,
but make sure it is
seated fully into the
filter housing.
WARNING
Filter
Body
Filter
Core
Spring
Filter
Housing
O-ring
Filter
Housing
Replacing the Potentiometer
Electrostatic discharge (ESD) potential could cause
damage to electronic pressure control. Use SprayTECH
ESD wrist strap P/N 0507958 or equivalent when working
on electronic pressure control.
1. Perform the Pressure Relief Procedure.
2. Pry off the pressure control knob cap to expose the knob
tension nut.
3. Turn the pressure control knob fully counterclockwise to
the minimum pressure setting.
4. Using a 5/16” socket, loosen the tension nut in the center
of the knob. Remove the knob.
5. Using a Phillips screwdriver, remove the four screws that
secure the electronic pressure control (EPC) assembly to
the EPC housing. Carefully remove the EPC assembly
from the housing. Gently move the assembly away from
the sprayer and allow the assembly to hang from the
housing.
6. Hold the potentiometer inside the EPC housing while
using a 1/2” thin wall socket to remove the seal nut that
secures the potentiometer to the mounting plate. Remove
the potentiometer from the EPC housing.
7. Carefully remove the potentiometer wires from their
connection point on the EPC board.
8. Insert the stem of the new potentiometer through the hole
in the mounting plate from inside the EPC housing.
Position the protruding tab on the potentiometer face into
the hole on the underside of the mounting plate (the wires
will face the open side of the EPC housing).
9. Thread the seal nut onto the threaded portion of the stem
and tighten using a 1/2” thin wall socket.
Do not over-tighten the seal nut.
10. Turn the potentiometer stem fully counterclockwise.
11. Place the pressure control knob on the potentiometer
stem with the indicator tab resting at the “minimum
pressure” tab on the mounting plate.
12. Tighten the knob tension nut using a 5/16” socket.
Do not over-tighten the knob tension nut. Over-tightening
will damage the potentiometer.
13. Connect the potentiometer wires to the EPC board. The
protruding tab on the EPC board connector will mate with
the slot on the potentiometer wires connector. The
connector on the end of the potentiometer wires and the
connector on the EPC board will mate only one way. Do
not force the connectors together.
14. Carefully place the EPC assembly over the EPC housing
taking care not to pinch any wires.
15. Install the four screws that secure the EPC assembly to
the EPC housing. Tighten securely.
Replacing the Pump ON/OFF Switch
Electrostatic discharge (ESD) potential could cause
damage to electronic pressure control. Use SprayTECH
ESD wrist strap P/N 0507958 or equivalent when working
on electronic pressure control.
1. Perform the Pressure Relief Procedure.
2. Using a Phillips screwdriver, remove the four screws that
secure the electronic pressure control (EPC) assembly to
the EPC housing. Carefully remove the EPC assembly
from the housing. Gently move the assembly away from
the sprayer and allow the assembly to hang from the
housing.
3. Locate the bottom of the pump ON/OFF switch inside the
EPC housing.
4. Disconnect the switch wires from the pump ON/OFF
switch. Remember the locations of each of the two wires
(label the wires, if necessary).
5. Depress the mounting tabs on each corner of the pump
ON/OFF switch inside the EPC housing and remove the
switch through the top of the housing.
6. Snap the new pump ON/OFF switch into the switch hole
in the EPC housing.
7. Connect the two switch wires to the new pump ON/OFF
switch. Make sure the wires are connected to the
corresponding terminals from which they were removed
(refer to the labels created earlier in this procedure or the
electrical schematic in the Parts List section of this
manual).
8. Carefully place the EPC assembly over the EPC housing
taking care not to pinch any wires.
9. Install the four screws that secure the EPC assembly to
the EPC housing. Tighten securely.
© SprayTECH. All rights reserved. 9
EPC
Assembly
Screw
EPC
Assembly
EPC
Board
Potentiometer
Cap
Pressure Control Knob
Seal Nut
EPC
Housing
EPC
Assembly
Screw
EPC
Assembly
EPC
Board
Pump ON/OFF
Switch