Graco Inc 310813D User Manual

Repair

GMAX™ 3400
Airless Sprayers

Korean patent: 10-0647761

310813D

- For Portable Airless Spraying of Architectural Coatings and Paints -

3300 psi (22.8 MPa, 228 bar) Maximum Working Pressure

Read all warnings and instructions

ti5944a

248664 ✓✓
248666 ✓✓

ti5523a

ti5447a

310802 311861

309250 309640

Graco Inc. P.O. Box 1441 Minneapolis, MN 55440-1441

Copyright 2005, Graco Inc. is registered to I.S. EN ISO 9001

ti5944a

Contents

Manual Conventions

WARNING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Drive Housing and Connecting Rod . . . . . . . . . . . 8

Pinion Assembly/Clutch Armature/Clamp . . . . . . . 9

Clutch Housing . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Pressure Control . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Displacement Pump . . . . . . . . . . . . . . . . . . . . . . . 14

Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Manual Conventions

WARNING

Hazard Symbol

WARNING: a potentially hazardous situation which, if

not avoided, could result in death or serious injury.
Warnings in the instructions usually include a symbol

indicating the hazard. Read the general Warnings
section for additional safety information.

GMAX 3400 Hi-Boy Sprayers . . . . . . . . . . . . . . . . 16

Pinion Housing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

GMAX 3400 Lo-Boy Sprayers . . . . . . . . . . . . . . . . 20

Pressure Control/Filter Assembly . . . . . . . . . . . . . 22

Pressure Control Wiring Diagram . . . . . . . . . . . . . 23

Complete Sprayers . . . . . . . . . . . . . . . . . . . . . . . . 24

Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Graco Standard Warranty . . . . . . . . . . . . . . . . . . . 26

CAUTION

CAUTION: a potentially hazardous situation which, if

not avoided, may result in property damage or
destruction of equipment.

Note

Additional helpful information.

2 310813D

Warning

Warning

The following warnings include general safety information for this equipment. Further product specific warnings may
be included in the text where applicable.

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.Do not fill fuel tank while engine is running or hot; shut off
engine and let it cool. Fuel is flammable and can ignite or explode if spilled on hot surface.

• Do not fill fuel tank while engine is running or hot; shut off engine and let it cool. Fuel is flammable
and can ignite or explode if spilled on hot surface.

• When flammable liquid is sprayed or used for flushing or cleaning, keep sprayer at least 20 feet (6 m)
away from explosive vapors.

• Eliminate all ignition sources; such as pilot lights, cigarettes, portable electric lamps, and plastic drop
cloths (potential static arc).

• Keep work area free of debris, including solvent, rags and gasoline.

• Do not plug or unplug power cords, or turn power or light switches on or off when flammable fumes
are present.

• Ground equipment and conductive objects in work area. See Grounding instructions.

• Use only grounded hoses.

• Hold gun firmly to side of grounded pail when triggering into pail.

• If there is static sparking or you feel a shock, stop operation immediately. Do not use equipment
until you identify and correct the problem.

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 medical attention.

• 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.

• Do not spray without tip guard and trigger guard installed.

• Engage trigger lock when not spraying.

• Follow Pressure Relief Procedure in this manual, when you stop spraying and before cleaning,
checking, or servicing equipment.

PRESSURIZED EQUIPMENT HAZARD

Fluid from the gun/dispense valve, leaks, or ruptured components can splash in the eyes or on skin and
cause serious injury.

• Follow Pressure Relief Procedure in this manual, when you stop spraying and before cleaning,
checking, or servicing equipment.

• Tighten all fluid connections before operating the equipment.

• Check hoses, tubes, and couplings daily. Replace worn or damaged parts immediately.

MOVING PARTS HAZARD

Moving parts can pinch 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 in this manual. Disconnect power or air supply.

310813D 3

Warning

WARNING

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. 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.

• Check equipment daily. Repair or replace worn or damaged parts immediately.

• 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 use hoses to pull equipment.

• Keep children and animals away from work area.

• Comply with all applicable safety regulations.

PRESSURIZED ALUMINUM PARTS HAZARD

Do not use 1,1,1-trichloroethane, methylene chloride, other halogenated hydrocarbon solvents or fluids
containing such solvents in pressurized aluminum equipment. Such use can cause serious chemical
reaction and equipment rupture, and result in death, serious injury, and property damage.

SUCTION HAZARD

Never place hands near the pump fluid inlet when pump is operating or pressurized. Powerful suction
could cause serious injury.

CARBON MONOXIDE HAZARD

Exhaust contains poisonous carbon monoxide, which is colorless and odorless. Breathing carbon mon­oxide can cause death. Do not operate in an enclosed area.

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.

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. Wait until equipment/fluid has cooled completely.

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 eyewear

• Clothing and respirator as recommended by the fluid and solvent manufacturer

•Gloves

• Hearing protection

RECOIL HAZARD

Brace yourself; gun may recoil when triggered and cause you to fall, which could cause serious injury.

4 310813D

Maintenance

Maintenance

Pressure Relief Procedure

WARNING

Read Injection Hazard, page 3; Burn Hazard, page 4

1. Lock gun trigger safety.

2. Turn engine ON/OFF switch to OFF.

3. Move pump switch to OFF and turn pressure control knob
fully counterclockwise.

4. Unlock trigger safety. Hold metal part of gun firmly to side
of grounded metal pail, and trigger gun to relieve
pressure.

5. Lock gun trigger safety.

6. Open pressure drain valve. Leave valve open until ready
to spray again.

If you suspect that the spray tip or hose is completely
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. Now clear
tip or hose.

CAUTION

For detailed engine maintenance and specifications,
refer to separate Honda Engines Owner's Manual,
supplied.

DAILY: Check engine oil level and fill as necessary.

DAILY: Check hose for wear and damage.

DAILY: Check gun safety for proper operation.

DAILY: Check pressure drain valve for proper operation.

DAILY: Check and fill the gas tank.

DAILY: Check level of TSL in displacement pump pack-

ing nut. Fill nut, if necessary. Keep TSL in nut to help
prevent fluid buildup on piston rod and premature wear
of packings and pump corrosion.

AFTER THE FIRST 20 HOURS OF OPERATION:

Drain engine oil and refill with clean oil. Reference
Honda Engines Owner's Manual for correct oil viscosity.

WEEKLY: Remove engine air filter cover and clean ele­ment. Replace element, if necessary. If operating in an
unusually dusty environment: check filter daily and
replace, if necessary.

Replacement elements can be purchased from your
local HONDA dealer.

AFTER EACH 100 HOURS OF OPERATION:

Change engine oil. Reference Honda Engines Owner's
Manual for correct oil viscosity.

SPARK PLUG: Use only BPR6ES (NGK) or W20EPR-U
(NIPPONDENSO) plug. Gap plug to 0.028 to 0.031 in.
(0.7 to 0.8 mm). Use spark plug wrench when installing
and removing plug.

310813D 5

Troubleshooting

Problem Cause Solution

Engine will not start Engine switch is OFF Turn engine switch ON

Engine is out of gasoline Refill gas tank. Honda Engines

Owner's Manual.

Engine oil level is low Try to start engine. Replenish oil, if

necessary. Honda Engines Owner's
Manual.

Engine operates, but displacement
pump does not operate

Spark plug is disconnected of dam­aged
Cold engine Use choke
Fuel shutoff lever is OFF Move lever to ON position
Oil is seeping into combustion
chamber

Pump switch is OFF Turn pump switch ON
Pressure setting too low Turn pressure adjusting knob clock-

Fluid filter (29) is dirty Clean filter. Page 22.
Tip or tip filter is clogged
Displacement pump piston rod is
stuck due to dried paint
Connecting rod is worn or damaged
Drive housing is worn or damaged Replace drive housing. Page 8.
Electrical power is not energizing
clutch field

Connect spark plug cable or replace
spark plug

Remove spark plug. Pull starter 3 to 4
times. Clean or replace spark plug.
Start engine. Keep sprayer upright to
avoid oil seepage

wise to increase pressure.

Clean tip or tip filter. Manual 311861.
Repair pump. Manual 309250.

Replace connecting rod. Page 8.

Check wiring connections. Page 11.

Reference pressure control repair. Page 13.

Troubleshooting

Reference wiring diagram. Page 23.

With pump switch ON and pressure turned to
MAXIMUM, use a test light to check for power
between clutch test points on control board.

Remove clutch wires from control
board and measure resistance across
clutch coil. At 70° F, the resistance
must be between 1.2 +0.2Ω; if not,
replace pinion housing.

Have pressure control checked by authorized

Graco dealer
Clutch is worn, damaged, or incor­rectly positioned
Pinion assembly is worn or damaged Repair or replace pinion assembly. Page 9.

Adjust or replace clutch. Page 9.

6 310813D

Problem Cause Solution

Pump output is low Strainer (16) is clogged Clean strainer.

Piston ball (206) is not seating Service piston ball. Manual 309250.
Piston packings are worn or damaged
O-ring (227) in pump is worn or damaged
Intake valve ball is not seating properly
Intake valve ball is packed with material
Engine speed is too low

Replace packings. Manual 309250.
Replace o-ring. Manual 309250.
Clean intake valve. Manual 309250.
Clean intake valve. Manual 309250.

Increase throttle setting. Manual 310802.
Clutch is worn or damaged Adjust or replace clutch. Page 9.
Pressure setting is too low Increase pressure. Manual 310802.
Fluid filter (29), tip filter or tip is

Clean filter. Manual 310802 or 311861.
clogged or dirty

Large pressure drop in hose with
heavy materials

Use larger diameter hose and/or

reduce overall length of hose. Use of

more than 100 ft of 1/4 in. hose signifi-

cantly reduces performance of sprayer.

Use 3/8 in. hose for optimum perfor-

mance (50 ft minimum).

Excessive paint leakage into throat
packing nut

Throat packing nut is loose Remove throat packing nut spacer.

Tighten throat packing nut just enough

to stop leakage.
Throat packings are worn or damaged
Displacement rod is worn or damaged

Fluid is spitting from gun Air in pump or hose

Replace packings. Manual 309250.

Replace rod. Manual 309250.

Check and tighten all fluid connections.

Prime pump. Manual 310802.
Tip is partially clogged Clear tip. Manual 311861.
Fluid supply is low or empty Refill fluid supply. Prime pump. Manual

310802. Check fluid supply often to

prevent running pump dry.

Pump is difficult to prime Air in pump or hose

Check and tighten all fluid connections.

Troubleshooting

Reduce engine speed and cycle pump

as slowly as possible during priming.
Intake valve is leaking Clean intake valve. Be sure ball seat is

not nicked or worn and that ball seats

well. Reassemble valve.
Pump packings are worn

Replace pump packings. Manual 309250.
Paint is too thick Thin the paint according to the sup-

plier's recommendations
Engine speed is too high Decrease throttle setting before prim-

ing pump. Manual 310802.

Clutch squeaks each time clutch
engages

Clutch surfaces are not matched to each
other when new and may cause noise

Clutch surfaces need to wear into each

other. Noise will dissipate after a day of

run time.

High engine speed at no load Misadjusted throttle setting Reset throttle to 3300 engine rpm at no

load
Worn engine governor Replace or service engine governor

310813D 7

Drive Housing and Connecting Rod

NOTE: The item numbers referenced are for the Hi-Boy

models. The Lo-Boy models may have different item
numbers. Use the Hi-Boy item number and part to find
the corresponding Lo-Boy part and item number.

Drive Housing and Connecting Rod

CAUTION

DO NOT use drive housing screws (18) to align or seat
bearing housing with drive housing. Align these parts
with locating pins, to avoid premature bearing wear.

Removal

WARNING

Read Injection Hazard, page 3; Burn Hazard, page 4

1. Relieve pressure, page 5.

IG. 1. Remove screws (10) and front cover (62).

2. F

3. Remove pump. Refer to Displacement Pump, Removal,

page 14.

4. Remove four screws (18) from drive housing (49).

CAUTION

Thrust washers may stick to grease inside of drive
housing. Do not lose or misplace.

5. Pull connecting rod (6) and lightly tap lower rear of drive
housing (49) with plastic mallet to loosen from pinion
housing (50). Pull drive housing and connecting rod
assembly off pinion housing.

6. Inspect crank (B) and connecting rod (6) for excessive
wear and replace parts as needed.

7. Install screws (18) in drive housing. Torque evenly to note
3 value in Fig. 1.

8. Install pump. Refer to Displacement Pump, Installation,
page 14.

50

52

57

49

1

56

C

18

9

ti5527a

B

3

18

2

D

2

E

10

62

10

6

93

5

8

54

4

A

15

2

ti5990a

12

57

56

1

2

17

Steel

Copper

1

Installation

1. Evenly lubricate inside of bronze bearing (C) in drive
housing (49) with high-quality motor oil. Liberally pack top
roller bearing (E), lower bearing (D) inside connecting rod
(6) with bearing grease.

2. Assemble connecting rod (6) to drive housing (49). Rotate
connecting rod to lowest position.

3. Apply grease to washers 52, 57 and 56. Install in order
shown in F

4. Lubricate gears with 0.26 pint of 110293 grease (supplied
with drive housing). Pack grease evenly around gears.

5. Clean mating surfaces of pinion and drive housings.

6. Align connecting rod with crank (B) and carefully align
locating pins in drive housing (49) with holes in pinion
housing (50). Push drive housing onto pinion housing or
tap into place with plastic mallet.

8 310813D

IG. 2.

FIG. 1

FIG. 2

Oil

2

Pack with bearing grease 110293

3

Torque to 130 - 150 in-ib (14 - 16.9 N m)

1

52

B

Pinion Assembly/Clutch Armature/Clamp

Pinion Assembly/Clutch Armature Removal

Pinion Assembly

If pinion assembly (50) is not removed from clutch housing
(51), do 1. through 3. Otherwise, start at 4.

WARNING

Pinion Assembly/Clutch Armature/Clamp

41

34

E

E

Read Injection Hazard, page 3; Burn Hazard, page 4

1. Relieve pressure, page 5.

2. Remove drive housing; page 8.

3. F

IG. 14. Disconnect clutch (A) and clutch (B) connectors

from control board.
a. Remove two screws (91) and swing down cover (77).
b. Remove strain relief 24b.

4.

FIG. 3

. Remove four screws (18) and pinion assembly (50).

18

51

ti5530a

50

18

FIG. 3

5. FIG. 4. Place pinion assembly (50) on bench with rotor
side up.

6. Remove four screws (41) and lock washers (34). Install
two screws in threaded holes (E) in rotor. Alternately
tighten screws until rotor comes off.

ti5481b

ti5987b

FIG. 4

7. FIG. 5. Remove retaining ring (50d).

8. Turn pinion assembly over and tap pinion shaft (50c) out
with plastic mallet.

50d

50c

50e

ti5532a

FIG. 5

Clutch Armature

9. FIG. 6. Use an impact wrench or wedge something
between clutch armature (38) and clutch housing to hold
engine shaft during removal.

10. Remove four screws (35) and lock washers (34).

11. Remove armature (38).

38

34

35

ti5533a

FIG. 6

310813D 9

Installation

Pinion Assembly/Clutch Armature/Clamp

Clutch Armature

1. FIG. 7. Lay two stacks of two dimes on smooth bench
surface.

2. Lay armature (38) on two stacks of dimes.

3. Press center of hub down to bench surface.

38

ti6008a

0.12 +.01 in. (3.0 +.25 mm)

dimes

FIG. 7

Clamp Removal

1. Do Engine Removal.

WARNING

Gasoline can spill and cause a fire or explosion if
engine is tipped on side.

4. Install armature (38) on engine drive shaft.

5. Install four screws (35) and lock washers (34) with torque
of 125 in-lb.

Pinion Assembly

6. Install o-ring (50e).

IG. 5. Tap pinion shaft (50c) in with plastic mallet.

7. F

8. Install retaining ring (50d) with beveled side facing up.

9. FIG. 4. Place pinion assembly on bench with rotor side up.

10. Apply locktite to screws. Install four screws (41) and lock
washers (34). Alternately torque screws to 125 in-lb until
rotor is secure. Use threaded holes to hold rotor.

IG. 3. Install pinion assembly (50) with four screws (18).

11. F

IG. 4. Connect clutch (A) and clutch (B) connectors to

12. F
control board.

Face of clutch housing

1

1.550 ±.010 in. (39.37±.25 mm)

2

Torque to 125 ±.10 in-lb (14 ±1.1 N·m)

33

Chamfer this side

44

2. Drain gasoline from tank according to Honda manual.

3.

FIG. 8

. Tip engine on side so gas tank is down and air

cleaner is up.

4. FIG. 9. Loosen two screws (35) on clamp (37),

5. Push screwdriver into slot in clamp (37) and remove
clamp.

ti6199a

FIG. 8

Clamp Installation

1. FIG. 9 Install engine shaft key (36)

2. Tap clamp (37) onto engine shaft (A). Maintain dimension
shown note 2. Chamfer must face engine.

3. Check dimension: Place rigid, straight steel bar (B) across
face of clutch housing (51). Use accurate measuring
device to measure distance between bar and face of
clamp. Adjust clamp as necessary. Torque two screws
(35) to 125 ±10 in-lb (14 ±1.1 N·m)

36

FIG. 9

1

51

2

37

35

4

3

B

ti5988a

A

10 310813D

Clutch Housing

Removal

1. Remove clamp. Do Clamp Removal, page 10.

2. FIG. 10. Remove four screws (60) and lock washers (59)
which hold clutch housing (51) to engine.

3. Remove screw (64) from under mounting plate (D).

4. Pull off clutch housing (51).

Installation

36

Clutch Housing

51

1. FIG. 10. Push on clutch housing (51).

2. Install four capscrews (60) and lock washers (59) and
secure clutch housing (51) to engine. Torque to 200 in-lb
(22.6 N·m).

3. Install screw (64) from beneath mounting plate (D).
Torque to 26 ft-lb (35.2 N·m).

Engine

Removal

NOTE: All service to the engine must be performed by

an authorized HONDA dealer.

1. Remove Pinion Assembly/Clutch Armature/Clamp and
Clutch Housing, as instructed on pages 9, 10 and 11.

IG. 11. Disconnect all necessary wiring.

2. F

3. FIG. 12. Remove two locknuts (3) and screws (2) from
base of engine.

4. Lift engine carefully and place on work bench.

1

To the field

2

1

To the engine

3

Ground

FIG. 10

ti5536a

59

60

D

64

2

ti5537a

3

IG. 12

F

Green

Installation

1. Lift engine carefully and place on cart.

IG. 12. Install two screws (2) in base of engine and

2. F

ti5535a

2

3

FIG. 11

310813D 11

secure with locknuts (3). Torque to 20 ft-lb (27.12 N·m).

3. FIG. 11. Connect all necessary wiring.

4. Install Pinion Assembly/Clutch Armature/Clamp and
Clutch Housing, as instructed on pages 9 and 10 and 11.

5. Set engine to 3300 rpm.

Pressure Control

On/Off Switch

Pressure Control

Removal

WARNING

Read Injection Hazard, page 3; Burn Hazard, page 4

1. Relieve pressure, page 5.

2. FIG. 13. Remove two screws (91) and swing down
cover (77).

3. Disconnect ON/OFF switch connector (B) from PC board.

4. Press in on two retaining tabs on each side of ON/OFF
switch (71) and remove switch from cover.

Installation

1. Install new ON/OFF switch (71) so tabs of switch snap
into place on inside of cover.

2. Connect ON/OFF switch connector (B) to PC board.

3. Swing up cover (77) and secure with two screws (91).

77

To Engine

24a

89

24b

FIG. 13

71

79

77

91 68

CLUTCH (A)

CLUTCH (B)

70a

78

20

63

30

69

B

D

70

ti5538a

90

E

12 310813D

Control Board

Pressure Control

Removal

WARNING

Read Injection Hazard, page 3; Burn Hazard, page 4

1. Relieve pressure, page 5.

2. FIG. 13. Remove two screws (91) and swing down
cover (77)

3. Remove strain relief bushing (24a).

4. Disconnect engine and ground wires.

5. Disconnect at control board (90):

• Lead (D) from potentiometer

Pressure Control Transducer

Removal

WARNING

Read Injection Hazard, page 3; Burn Hazard, page 4

• Lead (E) from transducer

• Lead (B) from ON/OFF switch

• Clutch wires

6. Remove four screws (89) and control board (90).

Installation

1. FIG. 13. Install control board (90) with four screws (89).

2. Connect at control board (90):

• Clutch wires

• Lead (B) from ON/OFF switch

• Lead (E) from transducer

• Lead (D) from potentiometer

3. Connect engine and ground wires.

4. Install strain relief bushing (24a).

5. Swing up cover (77) and secure with two screws (91).

Installation

1. FIG. 13. Install o-ring (63) and pressure control transducer
(20) in filter housing (30). Torque to 35 - 45 ft-lb.

2. Install transducer connector and rubber grommet in
control housing.

3. Connect lead (E) to control board (90).

4. Swing up cover (77) and secure with two screws (91).

1. Relieve pressure, page 5.

IG. 13. Remove two screws (91) and swing down

2. F
cover (77)

3. Disconnect lead (E) from control board (90).

4. Pull transducer connector through rubber grommet (78).

5. Remove pressure control transducer (20) and o-ring (63)
from filter housing (30).

Pressure Adjust Potentiometer

Removal

WARNING

Read Injection Hazard, page 3; Burn Hazard, page 4

1. Relieve pressure, page 5.

2. Fig. 13.Remove two screws (91) and swing down
cover (77).

3. Disconnect lead (D) from control board (90).

4. Loosen set screws on potentiometer knob (68) and remove
knob, shaft nut, lock washer and potentiometer (70).

5. Remove seal (69) from potentiometer.

Installation

1. Install seal (69) on potentiometer (70).

2. FIG. 13. Install potentiometer, shaft nut, lock washer and
potentiometer knob (68).
a.Turn potentiometer shaft clockwise to internal stop.

Assemble potentiometer knob (68) to strike pin on
cover (77).

b.After adjustment of step a., tighten both set screws in

knob 1/4 to 3/8 turn after contact with shaft.

3. Connect lead (D) to control board (90).

4. Swing up cover (77) and secure with two screws (91).

310813D 13

Displacement Pump

Displacement Pump

Removal

1. Flush pump.

WARNING

Read Injection Hazard, page 3; Burn Hazard, page 4

2. Relieve pressure, page 5.

IG. 15. Stop pump with piston rod (201) in its lowest

3. F
position.

4.

FIG. 14

. Loosen two screws (10) and remove pail hook (9).

10

ti5526a

6. FIG. 16. Loosen jam nut by hitting firmly with a 20 oz
hammer. Unscrew pump.

ti5545a

FIG. 16

Repair

9

See manual 309250 for pump repair instructions

FIG. 14

5. FIG. 15. Remove hose (93). Use screwdriver; push
retaining spring up; push out pin (8).

8

ti5541a

201

93

FIG. 15

14 310813D

Installation

WARNING

If pin works loose, parts could break off and project
through the air and result in serious injury or property
damage. Make sure pin is properly installed.

Displacement Pump

ti6111a

CAUTION

• Replacement pump comes with an outlet fitting
installed. Replace installed fitting with fitting marked
“GMAX 3400”.

• If the pump jam nut loosens during operation, the
threads of the bearing housing and drive train will
be damaged. Tighten jam nut as specified.

1. Fig. FIG. 17. Pull piston rod out. Screw in pump until holes
in connecting rod and piston rod align.

ti5546a

ti6110a

ti5544a

FIG. 18

4. FIG. 19. Fill packing nut with Graco TSL until fluid flows
onto the top of seal. Install pail hook (9).

ti5543a

1

Drive housing face

1

FIG. 19

FIG. 17

2. FIG. 11. Push pin (8) into hole. Push retaining ring spring
into groove all the way around connecting rod.

3.

FIG. 18

. Screw jam nut down onto pump until nut stops.

Screw pump up into drive housing until top threads of pump

FIG. 19

are flush with drive housing face (
and jam nut to align pump outlet to side. Tighten jam nut by
hand, then tap 1/8 to 1/4 turn with a 20 oz (maximum)
hammer to approximately 75 ±5 ft-lb (102 N·m). Connect
hose (93).

310813D 15

). Back off pump

Parts

Parts Drawing - GMAX 3400 Hi-Boy Sprayers

Parts

Ref 46

42

43

2

73

DETAIL A

99

72

DETAIL A

45

44

48

Ref 19

3

61

95

FOR PARTS
SEE PAGE 22

80

46

ti5524a

1

18

51

36

60

37

35

38

39

35

59

101

34

74

41

67

83

57

56

93

81

(Ref 93)

64

19

82

3

100

18

40

1

6

5

11

14

15

12

Bottom View

50

52

53

13

49

9

10

62

10

7

8

4

94

54

17

55

77

54

1

See parts page 18

16

16 310813D

Parts List - GMAX 3400 Hi-Boy Sprayers

Parts

Model 248664

Ref.
No. Part No. Description Qty.

1 108879 ENGINE, gasoline, 4.0 HP 1
2 110837 SCREW, flange, hex 2
3 110838 NUT, lock 2
4 246428 PUMP, displacement, st 1

Manual 309250
5 119789 FITTING, elbow, street, 45°, 1/4 npt 2
6 287053 ROD, connecting 1
7 195150 NUT, jam, pump 1
8 196762 PIN, straight 1
9 15C146 HOOK, pail 1
10 117501 SCREW, mach, hex washer hd 4
11 115099 WASHER, garden hose 1
12 15E813 NUT, jam 1
13 15B652 WASHER, suction 1
14 103413 O-RING 2
15 15E805 TUBE, intake (3400) 1
16 246385 STRAINER, 7/8-14 unf 1
17 276888 CLIP, drain line 1
18 119426 SCREW, mach, hex washer hd 8
19 287411 FRAME, cart (GMAX 3400 hi) 1
34 105510* WASHER, lock, spring (hi-collar) 10
35 108803 SCREW, hex, socket head 6
36 183401 KEY, parallel 1
37 193680 COLLAR, shaft 1
38 * ARMATURE, clutch, 4 in. 1
39 * HUB, armature 1
40 * ROTOR, clutch, 4 in. 1
41 101682* SCREW, cap, sch 4
42 112827 BUTTON, snap 2
43 192027 SLEEVE, cart 2
44 108068 PIN, spring straight 2
45 183350 WASHER, 2
46 245245 HANDLE, cart 1

Ref.
No. Part No. Description Qty.

48 109032 SCREW, mach, pnh 4
49 287483 HOUSING, drive, 3400 1

includes 9, 10, 18 & grease 110293
50 287376 HOUSING, pinion, 3400 1
51 15E535 HOUSING, clutch, mach, 3400 1
52 116074 WASHER, thrust 1
53 287484 CRANK, GMAX 3400 1

includes 52, 56, 57
54 244240 HOSE, coupled, includes 55 1
55 241920 DEFLECTOR, threaded 1
56 180131 BEARING, thrust 1
57 107434 BEARING, thrust 1
59 100214 WASHER, lock 4
60 108842 SCREW, cap, hex hd 4
61 119420 WHEEL, pneumatic 2
62 287487 COVER, front, painted, includes 10 1
64 112395 SCREW, cap, flnghd 1
67 15C871 CAP, leg 2
72 237686 WIRE, ground assembly w/clamp 1
73 112798 SCREW, thread forming, hex hd 1
80 156306 WASHER, flat 2
82 119510 HOLDER, manual 1
83 15E736 BRACKET, holder, manual 1
93 241926 HOSE, coupled 1
94 15E850 LABEL, identification 1
95 15E891 CLIP, retaining 2
99▲ 15F638 LABEL, warning 1
100 114678 BUSHING, strain relief 1
101 119569 BUSHING, strain relief 1

▲ Replacement Danger and Warning labels, tags, and

cards are available at no cost

* Included in Clutch Replacement Kit 241109

310813D 17

Parts Drawing and List - Pinion Housing

Ref No. 50: Pinion Housing

No. Part No. Description Qty

50 PINION HOUSING 1
50a 287482 KIT, repair, coil 1
50b 105489 PIN 2
50c* 287485 PINION SHAFT 1
50d* 113094 RETAINING RING, large 1

* Must be ordered separately

Parts

50b

50a

50d

50c

50e

ti5539a

18 310813D

Notes

Parts

310813D 19

Parts Drawing - GMAX 3400 Lo-Boy Sprayers

Parts

Ref 46

42

43

73

DETAIL A

99

72

DETAIL A

45

44

48

Ref 19

46

1

Bottom View

18

51

36

60

37

2

35

38

39

35

40

1

50

52

53

59

101

49

9

10

62

64

41

34

3

10

67

ti5525a

57

56

18

6

95

61

80

19

100

74

82

3

83

93

5

6a

7

94

8

4

54

11

14

81

17

16

15

55

FOR PARTS
SEE PAGE 22

(Ref 93)

54

1

77

See parts page 18

20 310813D

Parts List - GMAX 3400 Lo-Boy Sprayers

Parts

Model 248666

Ref
No. Part No. Description Qty

1 108879 ENGINE, gasoline, 4.0 HP 1
2 110837 SCREW, flange, hex 2
3 110838 NUT, LOCK 2
4 246428 PUMP, displacement, st 1

Manual 309250
5 119789 FITTING, elbow, street, 45°, 1/4 npt 2
6 287053 ROD, connecting; includes 6a, 8 1
6a 196750 RING, retaining 1
7 195150 NUT, jam, pump 1
8 196762 PIN, straight 1
9 15C146 HOOK, pail 1
10 117501 SCREW, mach, hex washer hd 4
11† 115099 WASHER, garden hose 1
12 15E813 NUT, jam 1
14† 103413 PACKING, o-ring 2
15† 287416 HOSE, suction 1
16† 246385 STRAINER, 7/8-14 unf 1
17† 276888 CLIP, drain line 1
18 119426 SCREW, mach, hex washer hd 8
19 287411 FRAME, cart (GMAX 3400 Hi) 1
34 105510* WASHER, lock, spring (hi-collar) 10
35 108803 SCREW, hex, socket head 6
36 183401 KEY, parallel 1
37 193680 COLLAR, shaft 1
38 * ARMATURE, clutch, 4 in. 1
39 * HUB, armature 1
40 * ROTOR, clutch, 4 in. 1
41 101682* SCREW, cap, sch 4
42 112827 BUTTON, snap 2
43 192027 SLEEVE, cart 2
44 108068 PIN, spring straight 2
45 183350 WASHER 2
46 245245 HANDLE, cart 1

Ref
No. Part No. Description Qty

48 109032 SCREW, mach, pnh 4
49 287483 HOUSING, drive, 3400 1

includes 9, 10, 18 & grease 110293
50 287376 HOUSING, pinion, 3400 1
51 15E535 HOUSING, clutch, mach, 3400 1
52 116074 WASHER, thrust 1
53 287484 CRANK, GMAX 3400 1

includes 52, 56, 57
54† 244240 HOSE, coupled, includes 55 1
55† 241920 DEFLECTOR, threaded 1
56 180131 BEARING, thrust 1
57 107434 BEARING, thrust 1
59 100214 WASHER, lock 4
60 108842 SCREW, cap, hex hd 4
61 119420 WHEEL, pneumatic 2
62 287487 COVER, front, painted, includes 10 1
64 112395 SCREW, cap, flng hd 1
67 15C871 CAP, leg 2
72 237686 WIRE, gnd assy w/clamp 1
73 112798 SCREW, thread forming, hex hd 1
80 156306 WASHER, flat 2
82 119510 HOLDER, manual 1
83 15E736 BRACKET, holder, manual 1
93 241926 HOSE, coupled 1
94 15E850 LABEL, identification 1
95 15E891 CLIP, retaining 2
99▲ 15F638 LABEL, warning 1
100 114678 BUSHING, strain relief 1
101 119569 BUSHING, strain relief 1

▲ Replacement Danger and Warning labels, tags, and

cards are available at no cost
* Included in Clutch Replacement Kit 241109
† Included in Suction Hose Kit 249356

310813D 21

Pressure Control/Filter Assembly

GMAX 3400 Sprayers

Pressure Control/Filter Assembly

50 CLUTCH (A)

50 CLUTCH (B)

77

71

79

91 68

(A) to1 Engine

97

70a

78

89

71

20

69

63

24

70b

91

20

(A)

77

90

24

30

31

58

28

29

81

ti5540a

84

85

27

2625

22a

2221

22b

66

65

22 310813D

Pressure Control/Filter Assembly

GMAX 3400 Sprayers

Pressure Control/Filter Assembly

Ref. Part Description Qty.

20 243222 TRANSDUCER, pressure contl

includes 63
21 224807 BASE, valve 1
22 235014 VALVE, drain; includes 22a, 22b 1
24 119545 BUSHING, strain, relief 2
25 15C780 HANDLE, 1
26 15C972 PIN, grooved 1
27 164672 NIPPLE, adapter 1
28 15C766 TUBE, diffusion 1
29 FILTER, fluid

244071 30 mesh 1
244067 60 mesh, original equipment 1
244068 100 mesh 1

244069 200 mesh 1
30 15E284 HOUSING, filter 1
31 287285 CAP, filter, includes 28, 58 1
58 117285 O-RING 1
63 111457 O-RING 1

Ref. Part Description Qty.

65 248314 PLUG, auto clean, includes 66 1

1

66 15D541 SEAL, washer 1
68 116167 KNOB, potentiometer 1
69 198650 SPACER, shaft 1
70 241443

POTENTIOMETER; includes 70a, 70b
71 116752 SWITCH, rocker 1
77 249357

BOX, control

includes 68, 69, 70, 71, 79, 89, 90, 97
78 15E925 GASKET, transducer 1
79 119548 PLUG, cap 1
81 113161 SCREW, flange, hex hd 3
84 164672 ADAPTER 1
85 104813 PLUG, pipe 1
89 117317 SCREW, plastite, pan head 4
90 287486 CONTROL, board, 3400 1
91 116585 SCREW, mach, pan hd 6
97 15E856 LABEL, identification 1

DRIVE
HOUSING

PINON
HOUSING

1

1

Pressure Control
Wiring Diagram

TO GROUND

TO ENGINE

ON/OFF SWITCH

CLUTCH B CLUTCH A

CONTROL BOARD

POTENTIOMETER

TRANSDUCER

ti5542a

310813D 23

Complete Sprayers - with RAC X Tip, Gun & Hose

GMAX 3400 Airless Paint Sprayers
Includes items 201 to 204

Ref
No. Part No. Description Qty

201 248664 Hi-Boy Sprayer 1

See parts list on page 17

248666 Lo-Boy Sprayer 1

See parts list on page 21

202 240794 HOSE, grounded, nylon; 1/4 in. ID; 1

cpld 1/4 npsm(fbe); 50 ft (15 m);
spring guards both ends
3300 psi (227 bar, 27.7 MPa)

203 238358 HOSE, grounded, nylon; 3/16 in.

ID;
cpld 1/4 npsm(m) x 1/4 npsm(f)

swivel;
3 ft (0.9 m); spring guards both

ends

204 288420 CONTRACTOR II SPRAY GUN

Includes RAC X 517-size SwitchTip
and HandTite Guard
See 311861 for parts 1

1

Complete Sprayers - with RAC X Tip, Gun & Hose

204

203

ti5989a

202

24 310813D

Technical Data

Technical Data

Honda GX120 Engine

ANSI Power Rating @ 3600 rpm 4.0 Horsepower

(2.9 kW)

Maximum working pressure 3300 psi

(227 bar, 22.7 MPa)

Noise Level

Sound power 100 dBa

per ISO 3744

Sound pressure 86 dBa

measured at 3.1 feet (1 m)
Maximum delivery rating 0.75 gpm (2.84 liter/min)
Maximum tip size 1 gun with 0. 027 in. tip
Inlet paint strainer 12 mesh (893 micron)

stainless steel screen, reusable

Outlet paint filter 60 mesh (250 micron)

stainless steel screen, reusable
Pump inlet size 1¼-12 unf-2b
Fluid outlet size ¼ npsm from fluid filter
Wetted parts zinc-plated carbon steel,

PTFE, Nylon, polyurethane, UHMW polyethylene, fluo­roelastomer, acetal, leather, aluminum, tungsten carbide,
nickel- and zinc-plated carbon steel, stainless steel,
chrome plating

Dimensions

Sprayer

(without hose and gun)

248664 Hi-Boy 89 (40.4) 31.5 (80) 22.5 (58) 31 (79)
248666 Lo-Boy 89 (40.4) 31.5 (80) 22.5 (58) 31 (79)

310813D 25

Weight lb (kg) Height in. (cm) Width in. (cm) Length in. (cm)

Graco Standard Warranty

Graco Standard Warranty

Graco warrants all equipment referenced in this document which is manufactured by Graco and bearing its name to be free from defects in
material and workmanship on the date of sale to the original purchaser for use. With the exception of any special, extended, or limited warranty
published by Graco, Graco will, for a period of twelve months from the date of sale, repair or replace any part of the equipment determined by
Graco to be defective. This warranty applies only when the equipment is installed, operated and maintained in accordance with Graco’s written
recommendations.

This warranty does not cover, and Graco shall not be liable for general wear and tear, or any malfunction, damage or wear caused by faulty
installation, misapplication, abrasion, corrosion, inadequate or improper maintenance, negligence, accident, tampering, or substitution of
non-Graco component parts. Nor shall Graco be liable for malfunction, damage or wear caused by the incompatibility of Graco equipment with
structures, accessories, equipment or materials not supplied by Graco, or the improper design, manufacture, installation, operation or
maintenance of structures, accessories, equipment or materials not supplied by Graco.

This warranty is conditioned upon the prepaid return of the equipment claimed to be defective to an authorized Graco distributor for verification of
the claimed defect. If the claimed defect is verified, Graco will repair or replace free of charge any defective parts. The equipment will be returned
to the original purchaser transportation prepaid. If inspection of the equipment does not disclose any defect in material or workmanship, repairs will
be made at a reasonable charge, which charges may include the costs of parts, labor, and transportation.

Graco’s sole obligation and buyer’s sole remedy for any breach of warranty shall be as set forth above. The buyer agrees that no other remedy
(including, but not limited to, incidental or consequential damages for lost profits, lost sales, injury to person or property, or any other incidental or
consequential loss) shall be available. Any action for breach of warranty must be brought within two (2) years of the date of sale.

GRACO MAKES NO WARRANTY, AND DISCLAIMS ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE, IN CONNECTION WITH ACCESSORIES, EQUIPMENT, MATERIALS OR COMPONENTS SOLD BUT NOT
MANUFACTURED BY GRACO. These items sold, but not manufactured by Graco (such as electric motors, switches, hose, etc.), are subject to

the warranty, if any, of their manufacturer. Graco will provide purchaser with reasonable assistance in making any claim for breach of these
warranties.

In no event will Graco be liable for indirect, incidental, special or consequential damages resulting from Graco supplying equipment hereunder, or
the furnishing, performance, or use of any products or other goods sold hereto, whether due to a breach of contract, breach of warranty, the
negligence of Graco, or otherwise.

FOR GRACO CANADA CUSTOMERS

The Parties acknowledge that they have required that the present document, as well as all documents, notices and legal proceedings entered into,
given or instituted pursuant hereto or relating directly or indirectly hereto, be drawn up in English. Les parties reconnaissent avoir convenu que la
rédaction du présente document sera en Anglais, ainsi que tous documents, avis et procédures judiciaires exécutés, donnés ou intentés, à la suite
de ou en rapport, directement ou indirectement, avec les procédures concernées.

ADDITIONAL WARRANTY COVERAGE

Graco does provide extended warranty and wear warranty for products described in the Graco Contractor Equipment Warranty Program.

TO PLACE AN ORDER, contact your Graco distributor, or call 1-800-690-2894 to identify the nearest distributor.

All written and visual data contained in this document reflects the latest product information available at the time of publication.

Graco reserves the right to make changes at any time without notice.

English GN 310813 MM 310813

Graco Headquarters: Minneapolis

International Offices: Belgium, Korea, China, Japan

GRACO INC. P.O. BOX 1441 MINNEAPOLIS, MN 55440-1441

http://www.graco.com

Written in U.S.A. 2/2005, Rev 05/2009

26 310813D