Graco 235-459 Operation manual

308–235
Rev. F
Supersedes Rev
. E
INSTRUCTIONS-PARTS LIST
INSTRUCTIONS
This manual contains important
warnings and information.
READ AND KEEP FOR REFERENCE.
Flex Airless Spray Gun
5000 psi (345 bar) MAXIMUM WORKING PRESSURE
Model 235–457, Series C
Bare gun.
Model 237–691, Series B
Includes RAC  IV DripLess  T ip Guard, 517 size
SwitchTip , and 2 finger trigger .
Model 235–459, Series D
Includes RAC  IV DripLess  T ip Guard, 517 size
SwitchTip , and 2 finger trigger .
Model 235–458, Series C
Includes the Standard (non-reversing) DripLess 
T
ip Guard. Spray tip not included; order separately .
Patents Pending
GRACO INC. P.O. BOX 1441 MINNEAPOLIS, MN 55440–1441
COPYRIGHT 1992, GRACO INC.
Graco Inc. is registered to I.S. EN ISO 9001
Model 235–458
Model 235–459
01460


Table of Contents
Warnings 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation/Operation 4 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pressure Relief Procedure 5. . . . . . . . . . . . . . . . . . .
System Requirements 5. . . . . . . . . . . . . . . . . . . . . . .
How to Use the Gun Trigger Safety 5. . . . . . . . . . .
How to Use the Gun 6. . . . . . . . . . . . . . . . . . . . . . . .
How to Adjust the Spray Pattern 6. . . . . . . . . . . . . .
How to Clean the Spray T ip
and Clear a Spray T ip Obstruction 7. . . . . . . . . . . .
How to Check the Gun Dif fuser 8. . . . . . . . . . . . . . . .
How to Clean the Filter 6. . . . . . . . . . . . . . . . . . . . . . . .
How to Flush the Gun 8. . . . . . . . . . . . . . . . . . . . . . . . .
Service 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Drawing 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Technical Data 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Graco Phone Numbers 14. . . . . . . . . . . . . . . . . . . . . . . . .
Warranty 16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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
or destruction of 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 .

This equipment is for professional use only .

Read all instruction manuals, tags, and labels before operating the equipment.
 Use the equipment only for its intended purpose. If you are not sure, call your Graco distributor .

Do not alter or modify this equipment.
 Check equipment daily . Repair or replace worn or damaged parts immediately .
 Do not exceed the maximum working pressure of the lowest rated system component. Refer to the
T echnical Data on page 14 for the maximum working pressure of this equipment.
 Use 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.
 Do 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.
 Do not use hoses to pull equipment.
 Route hoses away from traffic areas, sharp edges, moving parts, and hot surfaces. Do not expose
Graco hoses to temperatures above 66  C (150  F) or below –40  C (–40 F).
W
ear hearing protection when operating this equipment.
 Do not lift pressurized equipment.
 Comply with all applicable local, state, and national fire, electrical, and safety regulations.

 
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 .

Fluid injected into the skin might look like just a cut, but it is a serious injury . Get immediate medi -
cal attention.

Do not point the gun at anyone or at any part of the body .

Do not put your hand or fingers over the spray tip.
 Do not stop or deflect leaks with your hand, body , glove or rag.
 Do not “blow back” fluid; this is not an air spray system.
 Always have the tip guard and the trigger guard on the gun when spraying.
 Check the gun dif fuser operation weekly . See page 8.
 Be sure the gun trigger safety operates before spraying.
 Lock the gun trigger safety when you stop spraying.
 Follow the Pressure Relief Procedure on page 5 if the spray tip clogs and before cleaning,
checking or servicing the equipment.
T ighten all fluid connections before operating the equipment.
 Check the hoses, tubes, and couplings daily . Replace worn or damaged parts immediately.
Do not repair high pressure couplings; you must replace the entire hose.
 Fluid hoses must have spring guards on both ends, to help protect them from rupture caused by
kinks or bends near the couplings.
MOVING P ARTS HAZARD
Moving parts can pinch or amputate your fingers.
 Keep clear of all moving parts when starting or operating the pump.
 Before servicing the equipment, follow the Pressure Relief Procedure on page 5 to prevent the
equipment from starting unexpectedly .
RECOIL HAZARD
Due to the high pressure fluid emitted, a strong recoil action may occur when you trigger this gun. If
you are unprepared, your hand could be forced back toward your body or you could lose your balance
and fall, resulting in serious injury .

4308-235
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
.

If 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.
 Provide fresh air ventilation to avoid the buildup of flammable fumes from solvents or the fluid
being sprayed.
 Keep the spray area free of debris, including solvent, rags, and gasoline.
 Electrically disconnect all equipment in the spray area.
 Extinguish all open flames or pilot lights in the spray area.
 Do not smoke in the spray area.
 Do not turn on or of f any light switch in the spray area while operating or if fumes are present.
 Do not operate a gasoline engine in the spray area.
 Ground the equipment and the object being sprayed. Refer to your pump instruction manual.
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.
 Know the specific hazards of the fluid you are using.
 Store hazardous fluid in an approved container . Dispose of hazardous fluid according to all local,
state and national guidelines.
 Always wear protective eyewear , gloves, clothing and respirator as recommended by the fluid and
solvent manufacturer .

 
Installation/Operation
Pressure Relief Procedure
WARNING
INJECTION HAZARD
The system pressure must be manually
relieved to prevent the system from
starting or spraying accidentally . Fluid
under high pressure can be injected through the
skin and cause serious injury . T o reduce the risk of
an injury from injection, splashing fluid, or moving
parts, follow the Pressure Relief Procedure
whenever you:
 are instructed to relieve the pressure,
 stop spraying,
 check or service any of the system equipment,
 or install or clean the spray tips.
1. Lock the gun trigger safety .
2. Shut of f the power supply to the pump. Close any
bleed-type master air valves.
3. Unlock the gun trigger safety .
4.
Hold a metal part of the gun firmly to the side of a
grounded metal pail, and trigger the gun to relieve
pressure.
5.
Lock the gun trigger safety .
6.
Open the drain valve (required in your system),
having a container ready to catch the drainage.
7. Leave the drain valve open until you are 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 the
tip guard retaining nut or hose end coupling and relieve
pressure gradually , then loosen completely . Now clear
the tip or hose.
System Requirements
WARNING
Keep the wallet-sized warning card provided with
this gun with the operator at all times. The card
contains important treatment information should an
injection injury occur . Additional cards are available
at no charge from Graco Inc.
WARNING
Be sure your system has a bleed-type master air
valve (pneumatic pumps only) and a pressure drain
valve. These accessories help reduce the risk of
serious bodily injury , including fluid injection,
splashing in the eyes or on the skin, or injury from
moving parts, if you are adjusting or repairing the
pump or gun.
1. The bleed-type master air valve (air-powered
pumps only) relieves air trapped between this
valve and the pump after the air regulator is shut
off. T rapped air can cause the pump to cycle
unexpectedly.
2.
The pressure drain valve assists in relieving fluid
pressure in the displacement pump, hose and gun:
triggering the gun to relieve pressure may not be
sufficient.
3.
Strain the fluid you are spraying if it contains
particles which could clog the spray tip.
How to Use the Gun Trigger Safety
1. To lock the gun trigger safety , turn the latch (A) to
a right angle with the gun body . See Fig. 1.
2. T o unlock the gun trigger safety , push the latch (A)
out and turn it parallel with the gun body .
Fig. 1
LOCKED
UNLOCKED
01464


Installation/Operation
How to Use the Gun
1. Guide a grounded fluid hose (with spring guard)
through the hose guard (14) and connect the hose
to the gun inlet. See Fig. 2.
2. With no tip installed, start the pump. Flush the
pump according to the instructions supplied with it.
Prime the system with the fluid.
WARNING
T o reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 5.
3. Relieve the pressure. Be sure the gun trigger
safety is locked. See Fig. 1.
4. Model 235–459: Unscrew the tip guard (1) and
install the tip (A) and the gasket (2d) in the nut of
the tip guard. Screw the assembly firmly onto the
gun. T ighten the assembly with a wrench. See
Fig. 2.
NOTE: If the gasket (2d) is not installed, the gun
will leak.
5. Models 235–459 and 237–691: install the
SwitchT ip (19) and the tip guard (18). See manual
308–644, supplied.
Fig. 2
2d
01463
A
1
18
19 14
6.
Start the pump. Adjust the fluid pressure until the
spray is completely atomized. Use the lowest
pressure necessary to get the desired results.
Higher pressure may not improve the spray pattern
and will cause premature tip wear and pump wear .
7.
If adjusting the pressure does not give a good
spray pattern, follow the Pressure Relief Proce -
dure
on page 5 and then try another tip size.
8. Use a full-open, full-close triggering action. Hold
the gun about 14 in. (350 mm) from and at right
angles to the work surface. Don’t swing the gun in
an arc. Practice to find the best length and speed
of stroke.
How to Adjust the Spray Pattern.
1. To adjust the spray pattern direction, follow the
Pressure Relief Procedure on page 5. Loosen
the tip guard retaining nut (B). T urn the tip guard/
tip groove horizontally (C) for a horizontal pattern
and vertically (A) for a vertical pattern. T
ighten the
retaining nut.
2. The spray tip orifice and spray angle determines
the coverage and size of the pattern. When more
coverage is needed, use a larger spray tip rather
than increasing the fluid pressure.
CAUTION
The openings in the tip guard reduce paint buildup on
the tip guard while spraying. Any damage to the
sharp edges of the openings causes paint to collect
at that area. Never hang the gun by the tip guard.
A
BC
KEY
ATip
guard shown in position for
vertical spray pattern
B Retaining nut
CT ip guard shown in position for
horizontal spray pattern
Fig. 3

 
Installation/Operation
How to Clean the Spray Tip
and Clear a Spray Tip Obstruction.
WARNING
To reduce the risk of fluid injection or splashing in
the eyes or on the skin, do not hold a hand, body
or rag in front of the spray tip when cleaning or
checking a clogged tip. Point the gun toward the
ground or into a waste container when checking to
see if the spray tip is cleared.
Do not try to “blow back” paint; this is not an air
spray gun.
Do not wipe fluid buildup of f the gun or spray tip
until pressure is relieved.
Cleaning during the day.
1. Follow the Pressure Relief Procedure, page 5.
2. Clean the front of the tip frequently during the day
to help reduce buildup. Also clean the tip and tip
guard at the end of each work day . Use a solvent-
soaked brush to clean the spray tip.
Clearing an obstruction.
If the spray tip clogs while spraying, immediately stop
spraying, then:
Gun 235–458 – with standard tip guard
1. Engage the trigger safety latch, open the pressure
drain valve.
2. Remove the spray tip and blow out the obstruction
by applying air to the front of the spray tip. Or , let
the spray tip and gun nozzle soak to dissolve the
obstruction. If it won’t dissolve, jar it out by tapping
the back of the spray tip against a flat surface.
CAUTION
Never soak the entire gun in solvent. Prolonged
exposure to solvent can ruin the packings.
Gun 235–459 and 237–691– with RAC IV tip guard
1. Engage the trigger safety latch. Rotate the RAC IV
tip handle 180  . See Fig. 4.
2. Disengage the trigger safety latch. T rigger the gun
into a pail or onto the ground to remove clog.
3. Engage the trigger safety latch. Rotate the tip
handle to the spraying position.
4. If the tip is still clogged, lock the gun trigger safety ,
shut of f the sprayer and disconnect the power
source, and open the pressure drain valve to
relieve pressure. Clean the spray tip as shown in
manual 308–644, supplied with the RAC IV .
Fig. 4
KEY
A Handle
shown in
spraying position. T urn
handle 180  and
trigger gun to clear
clog.
A


Installation/Operation
How to Check the Gun Diffuser Operation
Check the dif fuser operation weekly . The gun dif fuser/
seat (2a) breaks up spray and reduces the risk of fluid
injection when the tip is not installed. Perform the test
below . If it fails, replace the entire Needle Kit, Part No.
235–474, as instructed on page 7. Dif fuser/seats are
not sold separately since the gun will leak if an old
needle is used with a new dif fuser/seat.
WARNING
T o reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 5.
1. Follow the Pressure Relief Procedure , page 5.
2. Remove the tip guard and spray tip.
3. Start the sprayer and adjust it to the lowest
pressure.
4. Aim the gun into a grounded metal pail while
holding it firmly to the pail. T rigger the gun. If the
fluid emitted is not dif fused into an irregular
stream, replace the entire needle kit immediately .
See Fig. 5.
Fig. 5
2a
How to Flush the Gun.
Always flush the pump and the gun before the fluid
being sprayed can dry in it.
NOTE: If it is available, the flushing procedure
provided in your pump or sprayer manual should be
used instead of this procedure.
WARNING
FIRE AND EXPLOSION HAZARD
Static sparking and splashing may cause
fire, explosion and serious injury . To
reduce static sparking and splashing,
always remove the spray tip from the gun, and hold
a metal part of the gun firmly to the side of a
grounded metal pail when flushing.
WARNING
T o reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 5.
1. Follow the Pressure Relief Procedure, page 5.
2. Remove the tip guard and spray tip. Soak and
clean the parts.
3. Put the pump intake in a grounded pail of water or
solvent.
4.
Start the pump at its lowest pressure.
5. T rigger the gun into the original pail. When solvent
appears, release the trigger .
6. Now trigger the gun into the solvent pail. Circulate
the fluid until the system is thoroughly flushed.
7. Follow the Pressure Relief Procedure , page 5.

 
Service
CAUTION
Do not attempt to install an old style needle in this
gun. The front of the new needle is marked with a +
below the Graco symbol.
Notes:
Use Needle Kit 235–474.
Use all the new parts for the best results. Parts
included in the kit are shown with one asterisk, (2a*).
Keep parts very clean. Dried paint or other contami -
nants cause friction which causes parts to wear faster .
Needle Replacement.
WARNING
To reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 5.
1. Follow the Pressure Relief Procedure , page 5.
2. Remove the hose, tip guard, spray tip and gasket.
3. Remove the dif fuser/seat (2a*) and gasket (2b*).
Remove the screw (12), pivot pin (1 1), and trigger
(8). See Fig. 6.
Fig. 6
8
2a*
2b*
12
02349
11

Lubricate,
then torque
to 20–25 ft–lb (27–34 N.m)

4. Insert a punch into the rear of the gun and tap it to
push the needle (2c*) out the front of the gun. See
Fig. 7.
Fig. 7
2c
02350
5. Clean the internal passages of the gun.
6. Grease the rings (A) of the new needle (2c*). See
Fig. 8.
Fig. 8
A

10 308-235
Service
7. Slide the rear of the needle (2c*) into the front of
the gun. Slide the tool (B), provided with the repair
kit, into the gun, around the needle. Lightly tap the
tool with a hammer or lightly press the tool against
a flat surface to seat the needle. See Fig. 9.
Remove the tool.
CAUTION
T apping or pressing the tool too hard may jam the
tool and damage the needle.
Fig. 9
2c
02351
B
8. Grease the end of the needle.
9. Grease the dif fuser/seat threads. Place the new
gasket (2b*) on the dif fuser/seat (2a*) and screw
the assembly into the fluid housing (7). T
orque to
20–25 ft-lb (27–34 N.m). See Fig. 6.
10. Install the trigger (8), pivot pin (1 1) and screw (12).
See Fig. 6.
NOTE: No needle or trigger adjustment is needed.