Graco 3A0243D User Manual

Repair

GMAX™ II 3900/5900/7900
TexSpray

5900HD/7900HD

Airless Sprayers

- For Portable Airless Spraying of Architectural Coatings and Paints -

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

IMPORTANT SAFETY INSTRUCTIONS

Read all warnings and instructions in this
manual. Save these instructions.

GMAX 3900

™

Model Hi-Boy

Premium

(QuikReel)
248683 ✓
248684 ✓
249335 ✓
258731 ✓
258736 ✓

Model Hi-Boy

Premium

(QuikReel)
248687 ✓
248688 ✓
258732 ✓
258737 ✓

Model Hi-Boy

Premium

(QuikReel)
258734 ✓

Model Hi-Boy

Premium

(QuikReel)
248700 ✓
248701 ✓
258733 ✓
258738 ✓

Model Hi-Boy

Premium

(QuikReel)
258735 ✓

Hi-Boy

Standard

GMAX 5900

Hi-Boy

Standard

TexSpray 5900 HD

Hi-Boy

Standard

GMAX 7900

Hi-Boy

Standard

GMAX 7900

Hi-Boy

Standard

Lo-Boy

Premium

(QuikReel)

Lo-Boy

Premium

(QuikReel)

Lo-Boy

Premium

(QuikReel)

Lo-Boy

Premium

(QuikReel)

Lo-Boy

Premium

(QuikReel)

Lo-Boy

Standard

Lo-Boy

Standard

Lo-Boy

Standard

Lo-Boy

Standard

Lo-Boy

Standard

3A0243D

EN

ti14916a

Related Manuals:
Operation 3A0242

Parts 3A0244
Gun 311861

Warning

Warning

The following are general warnings related to the setup, use, maintenance and repair of this equipment. Additional,
more specific, warnings may be found throughout the text of this manual, 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.

• 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 all equipment in the 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.

• Keep a working fire extinguisher in the work area.

SKIN INJECTION HAZARD

High-pressure fluid from gun, hose leaks, or ruptured components will pierce skin. This may look like just
a cut, but it is a serious injury that can result in amputation. Get immediate surgical treatment.

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

• Engage trigger lock when not spraying.

• 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.

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

• Tighten all fluid connections before operating the equipment.

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

MOVING PARTS HAZARD

Moving parts can pinch, cut or amputate fingers and other body parts.

• Keep clear of moving parts.

• Do not operate equipment with protective guards or covers removed.

• Pressurized equipment can start without warning. Before checking, moving, or servicing equip­ment, follow the Pressure Relief Procedure and disconnect all power sources.

2 3A0243D

Warning

WARNING

PRESSURIZED ALUMINUM PARTS HAZARD

Use of fluids that are incompatible with aluminum in pressurized equipment can cause serious chemi­cal reaction and equipment rupture. Failure to follow this warning can result in death, serious injury, or
property damage.

• Do not use 1,1,1-trichloroethane, methylene chloride, other halogenated hydrocarbon solvents or
fluids containing such solvents.

• Many other fluids may contain chemicals that can react with aluminum. Contact your material sup­plier for compatibility.

SUCTION HAZARD

Powerful suction could cause serious injury.

• Never place hands near the pump fluid inlet when pump is operating or pressurized.

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.

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, hearing loss, inhala­tion of toxic fumes, and burns. This equipment includes but is not limited to:

• Protective eyewear, and hearing protection.

• Respirators, protective clothing, and gloves as recommended by the fluid and solvent manufac­turer.

CALIFORNIA PROPOSITION 65

The engine exhaust from this product contains a chemical known to the State of California to cause
cancer, birth defects or other reproductive harm.

3A0243D 3

Maintenance

Maintenance

Pressure Relief Procedure

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.

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.

Premium Sprayers Engine Oil Funnel:

Use the supplied engine oil funnel when draining oil.

NOTE: 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 that all hose fittings are secure.

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.

ti6200a

OIL FUNNEL

4 3A0243D

Troubleshooting

Troubleshooting

Problem Cause Solution

E=XX is displayed Fault condition exists. Determine fault correction from table, page 14.

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

Engine is out of gasoline. Refill gas tank. Honda Engine Manual.
Engine oil level is low. Try to start engine. Replenish oil, if necessary.

Honda Engine Manual.

Spark plug disconnected or damaged. Connect spark plug cable or replace spark

plug.
Engine is cold. Use choke.
Fuel shutoff lever is OFF. Move lever to ON position.
Oil is seeping into combustion chamber. Remove spark plug. Pull starter 3 to 4 times.

Clean or replace spark plug. Start engine.

Keep sprayer upright to avoid oil seepage.

False tripping of WatchDog system.
EMPTY is displayed. Pump does not
run.

Engine operates, but displacement
pump does not operate

Operating conditions out of WatchDog
parameters.

Pump output is low, page 6.
Error code displayed. Reference Pressure Control repair, page 21.
Pump switch is OFF. Turn pump switch ON.
Pressure setting too low. Turn pressure adjusting knob clockwise to

Fluid filter is dirty. Clean filter.
Tip or tip filter is clogged. Clean tip or tip filter (see gun manual).
Displacement pump piston rod is stuck

due to dried paint.
Connecting rod is worn or damaged. Replace connecting rod. Page 15.
Drive housing is worn or damaged. Replace drive housing. Page 16.
Electrical power is not energizing clutch

field.

Turn pressure down. Contact Graco Technical

Assistance to adjust WatchDog parameters.

Operate without WatchDog active (see Opera-

tion manual).

increase pressure.

Repair pump (see pump manual).

Check wiring connections. Page 21.

Reference Digital Display Messages.

Page 14.

Reference wiring diagram. Page 21.

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 for 3900 - 1.2

+ 0.2 Ω, for 5900/7900 1.7 ± 0.2 Ω; 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 17.

3A0243D 5

Adjust or replace clutch. Page 19.

Troubleshooting

Problem Cause Solution

Pump output is low Strainer is clogged. Clean strainer.

Piston ball is not seating. Service piston ball (see pump manual).
Piston packings are worn or damaged. Replace packings (see pump manual).
O-ring in pump is worn or damaged. Replace o-ring (see pump manual).
Intake valve ball is not seating properly. Clean intake valve (see pump manual).
Intake valve ball is packed with mate-

rial.
Engine speed is too low. Increase throttle setting (see operation man-

Clutch is worn or damaged. Adjust or replace clutch. Page 17.
Pressure setting is too low. Increase pressure (see operation manual).
Fluid filter, tip filter or tip is clogged or

dirty.
Large pressure drop in hose with heavy

materials.

Excessive paint leakage into throat
packing nut

Fluid is spitting from gun Air in pump or hose. Check and tighten all fluid connections. Rep-

Pump is difficult to prime Air in pump or hose. Check and tighten all fluid connections.

Throat packing nut is loose. Remove throat packing nut spacer. Tighten

Throat packings are worn or damaged. Replace packings (see pump manual).
Displacement rod is worn or damaged. Replace rod (see pump manual).

Tip is partially clogged. Clear tip (see gun manual).
Fluid supply is low or empty. Refill fluid supply. Prime pump (see operation

Clean intake valve (see pump manual).

ual).

Clean filter (see gun manual).

Use larger diameter hose and/or reduce overall
length of hose. Use of more than 100 ft of 1/4
in. hose significantly reduces performance of
sprayer. Use 3/8 in. hose for optimum perfor­mance (50 ft minimum).

throat packing nut just enough to stop leakage.

rime pump (see operation manual).

manual). Check fluid supply often to prevent
running pump dry.

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. Reas-

semble valve.
Pump packings are worn. Replace pump packings (see pump manual).
Paint is too thick. Thin the paint according to the supplier's rec-

ommendations.
Engine speed is too high. Decrease throttle setting before priming pump

(see operation manual).

Clutch squeaks each time clutch
engages

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

Gallon counter not working Bad sensor, broken or disconnected

No display, sprayer operates Display damaged or has bad connec-

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

Worn engine governor. Replace or service engine governor.

wire. Displaced or missing magnet.

tion.

Clutch surfaces need to wear into each other.

Noise will dissipate after a day of run time.

Check connections. Replace sensor or wire.

Reposition or replace magnet.

Check connections. Replace display.

6 3A0243D

Fluid Pump Runs Constantly

Troubleshooting Procedure:

Troubleshooting

1. Perform Pressure Relief Procedure (page 4), turn
prime valve forward to SPRAY position, and turn
power switch OFF.

2. Remove control box cover.

With a pressure gauge plumbed into the paint
hose, start the engine. Turn pump switch ON.
Does sprayer exceed maximum pressure?

YES

Disconnect clutch wires from control board (see
diagram, page 12). Does the pump stop run­ning?

YES

Make sure clutch wires are plugged in (see dia­gram, page 12). Do the clutch test points read
10-18 DC volts?

YES

NO

NO

NO

Pump problem. See the proper fluid pump
manual for the sprayer for further trouble­shooting procedures.

Mechanical problem in the clutch pinion as­sembly (clutch may be close to the rotor).

Check for a short from the two clutch wires
to the frame. If shorted, repair or replace
faulty wire.

Unplug transducer from control board.

YES

Bad transducer.
Replace and test with a new one.

3A0243D 7

NO

Replace the control board.

Troubleshooting

Control Board Malfunction

Troubleshooting Procedure
(see following page for actual steps):

Remove control box cover. Turn
sprayer ON. Observe control board
Green and Red LED lights.

No light

Once Normal operation

Red light on
continuously

Green light on
continuously

Flashing See error code

Red light on
continuously with
potentiometer
OFF after a
replacement
board is installed

Go to step 4.
Is 1-3 Ohms
reading pres­ent?

YES

Control board
commanding
engine to run

WatchDog
enabled

section for further
troubleshooting

Model not
selected

YES

If low resistance is

NO

present in step 4,
the problem is a
shorted field.
Replace pinion.
If an open in the
wiring is present,
check pinion
wiring
connections.

Go to step 3.
Is 10-12
VDC
present?

NO

Go to step 1.
Does switch
test positive?

YES

Go to step 2.
Do you have
proper engine
voltage?

YES

Go to step 5.
Does the
clutch
engage?

YES

Replace the
potentiometer.

NO

NO

NO

Replace the
switch.

Check wiring
from J1 and J2
for proper con­nection. If proper
connection is
detected, repair
or replace engine
generator.

Connect
a test
transducer to
the board.
Does the
clutch
engage?

Replace

YES

the
control
board.

NO

Mechanical
problem. Repair
or replace
clutch/pinion
assembly.

8 3A0243D

Replace
the
transducer.

Control Board Malfunction (Steps)

Troubleshooting

BEEP

-

-

+

STEP 1.

Turn engine
OFF and set
meter to
continuity.

ti14938a

Pump
On/Off
Switch

To Ground

To Engine

5900/7900

On/Off Switch

3900

ti14939a

Engine
Generator

J1J2

J4J3

12 -20 AC

V

-

-

Control
Board

STEP 2.

Turn engine
ON. Set meter
to AC volts and
connect wires
to control
board.

Control
Board

+

J1

J2

Clutch Test Points

LED
D12

J5

J10

J9

To Clutch
Field

+

Pinion
Assembly

ti14943a

ti14940a

Control
Board

10-12 DC

V

-

Drive
Housing

STEP 3.

Leave engine
running and turn
switch ON. Turn
potentiometer to
high and set
meter to DC
volts.

+

+

Clutch
Field

WatchDog

Transducer

Premium Display Board

1-3 ohms

STEP 4.

Turn engine

Potentiometer

OFF and
unplug

ti14942a

Control
Board

Clutch Test Points

-

clutch wires.

-

Set meter to

+

Ohms.

+-

Clutch
Field

3A0243D 9

STEP 5.

Turn engine
ON and turn
switch ON.

Control
Board

J5

ti14941a

Troubleshooting

Convertible Electric Motor Will Not Run

Troubleshooting Procedure
(see following page for actual steps):

See Step 1. Is there
over 100 AC volts?

YES

See Step 3. Is there
over 100 DC volts?

YES

See engine test section.

NO

NO

See step 2. Is there
over 100 AC volts?

YES

Replace the power switch.

See Step 4. Is there
continuity through the
thermal sensor?

YES

Replace engine
control board.

NO

NO

Repair or replace
the power cord.

If engine is hot, let
cool and retest. If
step 4 still shows an
open, replace engine.

10 3A0243D