Graco GM3000 Operation manual

308620
Rev. K
INSTRUCTIONS-PARTS LIST
INSTRUCTIONS
This manual contains important
warnings and information.
READ AND KEEP FOR REFERENCE.
GM3000 Airless Paint Sprayer
3000 psi (210 bar, 21 MPa) Maximum Working Pressure
Model 231363, Series B
Basic Sprayer with Upright Cart
Model 231551
Same as 231363, with hose and gun, RACrX
HandTitetTip Guard, and 517 size SwitchTipt
Model 231550, Series B
Basic Sprayer with Lo–Boy Cart
Model 231552
Same as 231550, with hose and gun, RACrX
HandTitetTip Guard, and 517 size SwitchTipt
CAUTION
Always use a minimum hose length of 50 foot
(15 m) 1/4 inch ID or 50 foot (15 m) 3/8 inch ID. An
undersized hose may result in poor equipment
performance and damage to the clutch.
GRACO INC. P.O. BOX 1441 MINNEAPOLIS, MN 55440–1441
ECOPYRIGHT 1996, GRACO INC.
Graco Inc. is registered to I.S. EN ISO 9001
Model 231363 Shown
06001B

3086202
Table of Contents
Warnings 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Component Identification and Function 5. . . . . . . . . . . .
Setup 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fueling 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Startup 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Flushing 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Drive Housing, Connecting Rod, Crankshaft 16. . . . . .
Pressure Control 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pinion, Clutch, Clamp, Field, & Engine 23. . . . . . . . . . .
Pinion Housing 24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clutch 25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine 26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Field & Wiring Harness 27. . . . . . . . . . . . . . . . . . . . . . . . .
Clamp 27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clutch Housing 27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Reassembly 28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Displacement Pump Repair 31. . . . . . . . . . . . . . . . . . . . .
Pressure Control Parts list 33. . . . . . . . . . . . . . . . . . . . . .
Upright Sprayer Parts Drawing 34. . . . . . . . . . . . . . . . . .
Upright Sprayer Parts List 35. . . . . . . . . . . . . . . . . . . . . .
Lo-Boy Sprayer Parts Drawing 36. . . . . . . . . . . . . . . . . .
Lo-Boy Sprayer Parts List 37. . . . . . . . . . . . . . . . . . . . . .
Parts List & Drawing – Complete Sprayers 38. . . . . . .
Pinion Assembly Parts list and Drawing 38. . . . . . . . . .
Accessories 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Technical Data 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dimensions 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Graco Phone Number 39. . . . . . . . . . . . . . . . . . . . . . . . . .
Graco Warranty 40. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Symbols
Warning Symbol
WARNING
This symbol alerts you to the possibility of serious
injury or death if you do not follow the instructions.
Caution Symbol
CAUTION
This symbol alerts you to the possibility of damage to
equipment if you do not follow the instructions.
WARNING
INSTRUCTIONS
EQUIPMENT MISUSE HAZARD
Equipment misuse can cause the equipment to rupture or malfunction and result in serious injury.
DThis equipment is for professional use only.
DRead all instruction manuals, tags, and labels before operating the equipment.
DUse the equipment only for its intended purpose. If you are not sure, call your distributor.
DDo not alter or modify this equipment. Use only genuine Graco parts.
DCheck equipment daily. Repair or replace worn or damaged parts immediately.
DDo not exceed the maximum working pressure of the lowest rated system component. Refer to the
Technical Data on page 39 for the maximum working pressure of this equipment.
DUse fluids and solvents which are compatible with the equipment wetted parts. Refer to the Tech-
nical Data section of all equipment manuals. Read the fluid and solvent manufacturer’s warnings.
DDo not use hoses to pull equipment.
DRoute hoses away from traffic areas, sharp edges, moving parts, and hot surfaces. Do not expose
Graco hoses to temperatures above 82_C (180_F) or below –40_C (–40_F).
DDo not lift pressurized equipment.
DComply with all applicable local, state, and national fire, electrical, and safety regulations.
DWear hearing protection when operating this equipment.
DDo not use 1,1,1–trichloroethane, methylene chloride, other halogenated hydrocarbon solvents or
fluids containing such solvents in pressurized aluminum equipment. Such use could result in a
chemical reaction, with the possibility of explosion.

308620 3
WARNING
INJECTION HAZARD
Spray from the gun, leaks or ruptured components can inject fluid into your body and cause extremely
serious injury, including the need for amputation. Fluid splashed in the eyes or on the skin can also
cause serious injury.
DFluid injected into the skin may look like just a cut, but it is a serious injury. Get immediate medi-
cal attention.
DDo not point the gun at anyone or at any part of the body.
DDo not put your hand or fingers over the spray tip.
DDo not stop or deflect leaks with your hand, body, glove or rag.
DDo not “blow back” fluid; this is not an air spray system.
DAlways have the tip guard and the trigger guard on the gun when spraying.
DCheck the gun diffuser operation weekly. Refer to the gun manual.
DBe sure the gun trigger safety operates before spraying.
DLock the gun trigger safety when you stop spraying.
DFollow the Pressure Relief Procedure on page 12 if the spray tip clogs and before cleaning,
checking or servicing the equipment.
DTighten all fluid connections before operating the equipment.
DCheck the hoses, tubes, and couplings daily. Replace worn or damaged parts immediately. Do not
repair high pressure couplings; you must replace the entire hose.
DFluid hoses must have spring guards on both ends, to help protect them from rupture caused by
kinks or bends near the couplings.
TOXIC FLUID HAZARD
Hazardous fluid or toxic fumes can cause serious injury or death if splashed in the eyes or on the skin,
inhaled, or swallowed.
DKnow the specific hazards of the fluid you are using.
DStore hazardous fluid in an approved container. Dispose of hazardous fluid according to all local,
state and national guidelines.
DAlways wear protective eyewear, gloves, clothing and respirator as recommended by the fluid and
solvent manufacturer.
FUEL HAZARD
The fuel used in this unit is combustible and when spilled on a hot surface can ignite and cause a fire.
DDo not fill the fuel tank while the engine is running or hot.
EXHAUST HAZARD
The exhaust contains poisonous carbon dioxide which is colorless and odorless.
DDo not operate this equipment in a closed building.

3086204
WARNING
FIRE AND EXPLOSION HAZARD
Improper grounding, poor ventilation, open flames or sparks can cause a hazardous condition and
result in a fire or explosion and serious injury.
DIf there is any static sparking or you feel an electric shock while using this equipment, stop spray-
ing immediately. Do not use the equipment until you identify and correct the problem.
DProvide fresh air ventilation to avoid the buildup of flammable fumes from solvents or the fluid
being sprayed.
DKeep the spray area free of debris, including solvent, rags, and gasoline.
DDisconnect all electrical equipment in the spray area.
DExtinguish all open flames or pilot lights in the spray area.
DDo not smoke in the spray area.
DDo not turn on or off any light switch in the spray area while operating or if fumes are present.
DDo not operate a gasoline engine in the spray area.
DGround the sprayer to a true earth ground with the ground wire and clamp (supplied).
DUse only electrically conductive hoses.
MOVING PARTS HAZARD
Moving parts can pinch or amputate your fingers.
DKeep clear of all moving parts when starting or operating the sprayer.
DBefore servicing the equipment, follow the Pressure Relief Procedure on page 12 to prevent the
equipment from starting unexpectedly.
Liquids can be injected into the body by high pressure airless
spray or leaks – especially hose leaks.
Keep body clear of the nozzle. Never stop leaks with any part of the
body. Drain all pressure before removing parts.Avoid accidental
triggering of gun by always setting safety latch when not spraying.
Never spray without a tip guard.
In case of accidental skin injection, seek immediate
“Surgical Treatment”.
Failure to follow this warning can result in amputation or serious
injury.
FIRE AND
EXPLOSION HAZARD
SKIN INJECTION
HAZARD
READ AND UNDERSTAND ALL LABELS AND INSTRUCTION MANUALS BEFORE USE
Spray painting, flushing or cleaning equipment with flammable
liquids in confined areas can result in fire or explosion.
Use outdoors or in extremely well ventilated areas. Ground
equipment, hoses, containers and objects being sprayed.
Avoid all ignition sources such as static electricity from plastic
drop cloths, open flames such as pilot lights, hot objects such as
cigarettes, arcs from connecting or disconnecting power cords
or turning light switches on and off.
Failure to follow this warning can result in death or serious injury.
NOTE: This is an example of the DANGER label on your sprayer. This label is available in other languages, free of
charge. See page 39 to order.

308620 5
06001B
C
Fig. 1
E
F
D
A
G
M
B
H
R
T
P
S
U
N
J
K
Component Identification and Function
L
V
0016
0015
APressure Control Switch ON/OFF, enables/disables clutch function
BPressure Adjusting Knob Controls fluid outlet pressure
CAir Cleaner* Filters air entering the carburetor
DFuel Tank* Holds 0.66 gallons (2.5 liters) of [(R+M)/2]; 86 octane gasoline
EMuffler* Reduces noise of internal combustion
FSpark Plug Cable* Routes electrical current to spark plug
GFuel Valve* On/off valve to regulate fuel flow from gasoline tank to carburetor
HChoke* Enriches air/gasoline mixture for cold starting
JThrottle* Adjusts engine speed for large or small orifice spray tips
KEngine Switch* Enables/disables engine operation
LFluid Outlet Hose and spray gun are connected here
MPressure Control Controls clutch cycling to maintain fluid pressure.
NEngine* 4.0 HP gasoline engine
PClutch Transfers power from engine to drive assembly
RDrive Assembly Transfers power from clutch to displacement pump
SDisplacement Pump Provides fluid to be sprayed through spray gun
TFluid Filter Filters fluid between source and spray gun
UGrounding Clamp and Wire Grounds sprayer system
VPressure Drain Valve Relieves fluid pressure when open
*For more detailed explanations of these controls, refer to the Honda engine manual; supplied

3086206
Setup
CAUTION
To avoid damaging the pressure control, which may
result in poor equipment performance and component
damage, follow these precautions.
1. Always use nylon spray hose. Never use a wire
braid hose; it is too rigid to act as a pulsation
dampener.
2. Always use a minimum hose length of 50 foot
(15 m) x 1/4 inch ID or 50 foot (15 m) x 3/8 inch
ID hose.
3. Never install any shutoff device between the filter
(21) and the main hose. See Fig. 2.
4. Always use the main filter outlet (20) for a one
gun operation. Never plug this outlet.
1. Connect hose and gun. (Refer to Fig. 2.)
a. Remove the plastic cap from the 1/4 npsm (m)
filter outlet nipple (20). Screw the main fluid
hose onto the nipple. Read the CAUTION,
above.
b. Connect the whip end hose between the main
fluid hose and the inlet adapter of the gun.
c. Do not use thread sealant, and do not install
the spray tip yet!
WARNING
If you supply your own hoses and spray gun, be
sure the hoses are electrically conductive, that the
gun has a tip guard, and that each part is rated for
at least 3000 psi (210 bar, 21 MPa) Maximum
Working Pressure. This is to reduce the risk of
serious injury caused by static sparking, fluid
injection or over-pressurization and rupture of the
hose or gun.
2. Fill packing nut/wetcup. Fill the packing nut/wet-
cup (A) 1/3 full with Graco Throat Seal Liquid
(TSL), supplied. See Fig. 2.
3. Check the engine oil level. Refer to the Honda
engine manual, supplied. This is a summary of the
information: Remove one of the oil fill plugs (M);
the oil should be almost overflowing. See Fig. 3.
Add oil as necessary.
Recommended lubrication oil: Use a high-quality,
detergent oil, SAE 10W–30, classified “FOR
SERVICE SG or SF”, for regular use and for
breaking–in a new engine.
Fig. 2
20
A
46
21
21 Fluid Filter
46 Pressure drain valve
20 1/4 npsm(m) fluid outlet
A Wetcup 05832

308620 7
Setup
4. Be sure your system is properly grounded
before operating it. Connect the sprayer to a true
earth ground with the grounding wire and clamp
(80) ; for example, a cold water pipe or a ground
rod driven into the earth.
5. Fill the gas tank. See Fueling, page 8.
6. Flush the pump to remove the lightweight oil
which was left in the pump to protect it from corro-
sion.
a. Before using water–base paint, flush with
mineral spirits, followed by soapy water, and
then flush with clean water.
b. Before using oil–base paint, flush with mineral
spirits, only.
c. See Flushing on page 13 for the flushing
procedure.
7. Prepare the paint according to the manufacturer’s
recommendations.
a. Remove any skin that may have formed.
b. Stir the paint to mix the pigments.
c. Strain the paint through a fine nylon mesh bag
(available at most paint dealers) to remove the
particles that could clog the filter or spray tip.
This is probably the most important step
toward trouble–free spraying.
8. Keep the sprayer upright and level during
operation and whenever it is being moved. See the
CAUTION on page 10.
Fig. 3
K
L
80
M
0015
06906A

3086208
Fueling
WARNING
FIRE AND EXPLOSION HAZARD
Gasoline is extremely flammable and
explosive under certain conditions.
Always turn the engine switch (K) to off
before refueling. (Fig. 3)
Refuel in a well-ventilated area.
Do not smoke or allow flames or sparks in the area
where the engine is refueled or where the gasoline
is stored.
Do not overfill the tank. Make sure the gas fill cap
(L) is securely closed after refueling. (Fig. 3)
Be careful not to spill fuel when fueling. Fuel vapor
or spilled fuel can ignite. If any fuel is spilled, make
sure the area is dry before starting the engine.
1. Fuel specifications. Use automotive gasoline
with a pump octane number of 86 or higher, or a
research octane number of 91 or higher. Unleaded
fuel minimizes the combustion chamber deposits.
2. Gasolines containing alcohol (gasohol). Do not
use gasohol which contains methanol, if the gaso-
hol does not contain cosolvents and corrosion
inhibitors for methanol. Even if it does contain such
additives, do not use the gasohol if it contains
more than 5% methanol or 10 % ethanol.
NOTE: The Honda engine warranty does not cover
the damage resulting from the use of gasolines con-
taining a higher percentage of alcohol than mentioned
in step 2. See the Honda engine manual for more
information.
3. General. Do not use any oil and gasoline mixtures
or contaminated gasoline. Avoid getting any dirt,
dust or water in the fuel tank.
4. Tank Capacity. 0.66 gallons (2.5 liters). Always
leave at least 1/2 in. (13 mm) at the top of the tank
for expansion.
5. Shut off the engine before refueling.
6. After refueling, tighten the fuel tank cap firmly.

308620 9
Startup
Before You Start the Sprayer
1. See Flushing on page 12 to determine if you
should flush the sprayer.
2. Be sure the gas tank is full.
3. Check the engine oil level.
NOTE: The engine stops automatically, or will not
start, if it is low on oil. Refer to the oil fill procedure in
the Honda engine manual or to step 3, page 6.
4. Be sure the spark plug cable is firmly pushed
onto the plug.
Starting the Sprayer
NOTE: Refer to Fig. 1 as you start the sprayer.
1. When starting a sprayer that IS NOT PRIMED,
remove the spray tip.
2. Place the suction tube into the paint, water or
solvent container, depending on whether you are
flushing or are ready to spray.
3. Open the black fuel shutoff lever by pushing it in
the direction of the arrow.
CAUTION
Never try to start the engine unless fluid pressure is
relieved and the pressure control switch is OFF.
Trying to start the engine when it is pressurized
could damage the recoil system.
4. Move the pressure control switch to OFF.
5. To start the engine:
a. Turn the pressure adjusting knob all the way
counterclockwise to the lowest pressure set-
ting.
b. Slide the metal throttle lever away from the
fuel tank to maximum position (fully left).
c. If the engine is cold, close the choke by mov-
ing the gray lever.
d. If the engine is warm, close the choke by
moving the gray lever only half way or not at
all.
e. Turn the engine switch to ON.
WARNING
MOVING PARTS HAZARD
A rope which recoils too quickly may hit
someone and cause serious injury. The
rope could also jam in recoil assembly.
f. Hold the frame of the sprayer with one hand
and pull the starter rope rapidly and firmly.
Continue holding the rope as you let it return.
Pull and return the rope until the engine starts.
g. Open the choke as soon as the engine starts,
except in cold weather. In cold weather, leave
the choke closed for 10 to 30 seconds before
opening it to keep the engine running.
6. Unlock the gun trigger safety.

30862010
Startup
7. Prime the pump:
a. Place the suction tube in the bucket of paint,
water, or solvent.
b. Open the pressure drain valve.
c. Set engine speed to idle.
d. Move the pressure control switch to ON. Turn
the pressure adjusting knob slowly until the
sprayer starts.
e. Run the pump until fluid is flowing smoothly
from the pressure drain valve, indicating the
pump is primed.
f. Move the pressure control switch to OFF.
g. If the pump was primed with water or solvent,
remove the suction tube from the water or
solvent and place it in the paint. Repeat steps
b through f.
h. Close the pressure drain valve.
8. When the pump is primed:
a. Remove the spray tip.
b. Set the engine speed to full flow.
c. Move the pressure control switch to ON. Turn
the pressure adjusting knob slowly until the
sprayer starts.
d. Unlock the gun trigger safety.
e. Trigger the gun into the pail until fluid flows
from the gun. If pumping solvent or solvent–
based paint, hold a metal part of the gun firmly
against a grounded metal pail.
f. Release the gun trigger and lock the gun
trigger safety.
g. Move the pressure control switch to OFF.
h. Relieve pressure by opening the pressure
drain valve.
i. Close the pressure drain valve.
WARNING
INJECTION HAZARD
To reduce the risk of serious injury from
fluid injection, never operate the spray
gun with the tip guard removed.
9. Install the spray tip in the gun. See the separate
tip instruction manual, 308–644, supplied.
10. Move the pressure control switch to ON.
11. Adjust the engine speed and pump pressure.
Unlock the gun trigger safety. Trigger the gun onto
a test paper to check the spray pattern and atom-
ization. Turn the pressure adjusting knob until you
get a good pattern. Then slowly lower the throttle
setting as far as you can without changing the
spray pattern.
CAUTION
Always use the lowest needed fluid pressure and the
lowest needed throttle setting, to increase the life of
the sprayer. Higher settings cause excessive clutch
cycling, premature tip wear and premature pump
wear.
CAUTION
Close the black fuel shutoff lever whenever you are
transporting the sprayer to prevent fuel from flooding
the engine.
Keep the sprayer upright and level when operating it
and when transporting it. This prevents crankcase oil
from leaking into the combustion chamber, which
makes startup very difficult.