Graco 236-288 Operation manual

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INSTRUCTIONS–P ARTS LIST 308–316
Rev. D
Supersedes B
and PCN C
Foam Dispense Gun
150 psi (10 bar) Minimum Dynamic Working Air Pressure
180 psi (12 bar) Maximum Working Air Pressure
950 psi (66 bar) Maximum Working Fluid Pressure
Model 236–288, Series A
Includes a 0.215 in. (5.46 mm) diameter needle/nozzle assembly
Vsupply: +20 to 24 VDC
Imax: 50 mA
IMPORTANT!
This gun is intended for use only with the
Graco Shot Foam System to assure that
proper grounding and other safety devices
are in place .
U.S. Patent D346,729; 5,348,230
R.O.C. Patent 159444
Additional patent pending
GRACO INC. P.O. BOX 1441 MINNEAPOLIS, MN 55440–1441
COPYRIGHT 1994, GRACO INC.
This manual contains important
warnings and information.
READ AND RETAIN FOR REFERENCE
INSTRUCTIONS

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Symbols
Warning Symbol
WARNING
his 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
WARNING
INJECTION HAZARD
Spray from the gun, hose leaks, or ruptured components can inject fluid into your body and cause
extremely serious injury
, including the need for amputation. Splashing fluid in the eyes or on the skin
can also cause serious injury .
D Fluid injected into the skin might look like just a cut, but it is a serious injury . Get immediate
medical attention.
D
Do not point the gun at anyone or at any part of the body .
D
Do not put hand or fingers over the gun nozzle.
D Do not stop or deflect fluid leaks with your hand, body , glove, or rag.
D Be sure the piston rod safety operates before dispensing.
D Lock the piston rod safety when you stop dispensing and before wiping of f any buildup around the
nozzle.
D
Keep the tip of the nozzle and the nozzle head free of foam buildup. Foam buildup on the nozzle
can cause foam shots to be misdirected and splash foam in the eyes or on the skin.
D If the nozzle clogs, stop dispensing, lock the piston rod safety , and follow step 5 on page 8 to
clean the nozzle.
D Completely close the fluid manifold needle valves before removing the nozzle or cleaning, check -
ing, or servicing the gun. This will isolate the fluid pressure in the manifold and fluid hose.
DT ighten all the fluid connections before operating the equipment.
D Check the hoses, tubes, and couplings daily . Replace worn, damaged, or loose parts immediate -
ly
. Permanently coupled hoses cannot be repaired; replace the entire hose.
HOT MATERIAL HAZARD
Individual foam components will be heated to 180 _F (82_ C) maximum. The foam reaches approxi -
mately 350 _F (177_ C) immediately after the two components (resin and isocyanate) are mixed.
The foam, gun head, and other parts connected to the gun (including the hose, fittings, and tubing)
will be uncomfortable to the touch. T o avoid a burn or an injury from the foam adhering to the skin:
DW ear gloves when operating the gun.
D Do not come in contact with the dispensed material until it has cooled and cured.
D If you are burned, get emergency medical care at once. Do not pull the foam from your skin.

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WARNING
WARNING
PLURAL COMPONENT MATERIAL HAZARD
Before using this equipment, read the material manufacturer ’ s warnings and determine all facts relat -
ing to the materials used, including any of the potential hazards relating to toxic fumes, fires, explo -
sions, reaction times, and exposure of human beings to the individual components or their resultant
mixtures.
DW ear the appropriate protective clothing, gloves, eyewear , facemask, and respirator .
D
Store hazardous fluid in an approved container . Dispose of hazardous fluid according to all local,
state and national guidelines.
D Graco does not manufacture or supply any of the reactive chemical components that may be
used in this equipment and is not responsible for their ef fects. Graco assumes no responsibility
for loss, damage, expense or claims for personal injury or property damage, direct or consequen -
tial, arising from the use of such chemical components.
EQUIPMENT MISUSE HAZARD
Equipment misuse can cause the equipment to rupture, malfunction, or start unexpectedly and result
in serious injury .
D This equipment is for professional use only .
D
Read all instruction manuals, tags, and labels before operating the equipment.
D Use the equipment only for its intended purpose. If you are uncertain about usage, call Graco
T echnical Assistance at 1–800–543–0339.
D Do not alter or modify this equipment. Use only genuine Graco parts and accessories.
D Check the equipment daily . Repair or replace worn or damaged parts immediately .
D
Do not exceed the maximum working pressure of the lowest rated system component. This
equipment has a
950 psi (66 bar) maximum working fluid pressure and a 180 psi (12 bar)
maximum working air pressure .
D
Do not install a fluid shut-of f device at the fluid outlet of the heater or filter . Shutting of f only one
fluid component at the heater or filter outlet causes high back pressure, which can cause compo -
nent rupture.
D Route the hoses away from the traffic areas, sharp edges, moving parts, and hot surfaces. Do
not expose Graco hoses to temperatures above 180 _F (82_ C) or below –40 _F (–40_C).
D
Use fluids or solvents that are compatible with the equipment wetted parts. See the Technical
Data
section of all the equipment manuals. Read the fluid and solvent manufacturer ’ s warnings.
D Comply with all applicable local, state and national fire, electrical and other safety regulations.
INSTRUCTIONS

4 308-316
FIRE, EXPLOSION, AND ELECTRIC SHOCK HAZARD
Improper grounding, poor air ventilation, open flames, or sparks can cause a hazardous condition
and result in fire or explosion, electric shock and other serious injury .
D
All electrical wiring must be done by trained and qualified personnel.
D Ground the equipment and the object being sprayed. See Grounding the System on page 5.
D Provide fresh air ventilation to avoid the buildup of flammable fumes from solvent or the fluid be -
ing sprayed.
D Extinguish all the open flames or pilot lights in the spray area.
D Electrically disconnect all the equipment in the spray area.
D Keep the spray area free of debris, including solvent, rags, and gasoline.
D Do not turn on or of f any light switch in the spray area while operating or if fumes are present.
D Do not smoke in the spray area.
D Do not operate a gasoline engine in the spray area.
D If there is any static sparking while using the equipment, stop spraying immediately . Identify
and correct the problem.
WARNING
WARNING
Table of Contents
Symbols 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Warning 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pour Nozzle Performance Information 4. . . . . . . . . .
Terms 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Safety 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Grounding the System 5. . . . . . . . . . . . . . . . . . . . . .
Connecting the Hoses 6. . . . . . . . . . . . . . . . . . . . . . .
The Solvent Flushing System 6. . . . . . . . . . . . . . . .
Operation 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Piston Rod Safety Lock 7. . . . . . . . . . . . . . . . . . . . . .
General Startup 7. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lubricating Parts 9. . . . . . . . . . . . . . . . . . . . . . . . . . .
Needle/Nozzle Assembly Maintenance 9. . . . . . . .
Needle/Nozzle Assembly Repair or
Replacement 10. . . . . . . . . . . . . . . . . . . . . . . . . .
Air V alve Piston and Spool
Maintenance 14. . . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service 17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lubricating Parts 17. . . . . . . . . . . . . . . . . . . . . . . . . .
Tools 17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removing the Gun from the Production Line 18. .
Solenoid V alve 20. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Receptacle Assembly 21. . . . . . . . . . . . . . . . . . . . . .
Air V alve Piston Assembly 22. . . . . . . . . . . . . . . . . .
Piston Rod Safety 24. . . . . . . . . . . . . . . . . . . . . . . . .
Air V alve Spool Assembly 25. . . . . . . . . . . . . . . . . . .
Trigger Switch 27. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Assemble the Gun 28. . . . . . . . . . . . . . . . . . . . . . . . .
Install the Gun on the Production Line 29. . . . . . . .
Manifold Needle V alves Replacement 30. . . . . . . .
Parts 32 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Accessories 34 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Graco Phone Numbers 34. . . . . . . . . . . . . . . . . . . . . . .
Technical Data 35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Warranty 36 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pour Nozzle Performance Information
The 0.215 in. (5.46 mm) diameter nozzle was
designed to optimize pour foam quality at a flow rate of
80 grams per second, with the two foam components
heated to 150 _F (66_ C). Depending on the specific
system, these parameters may need to be adjusted
slightly to obtain the desired results.

5308-316
Installation
Terms
ISO: Isocyanate
RES:
Resin
Safety
For your safety , read all of the warnings and instruc -
tions in this manual, all system component manuals,
and the chemical manufacturer ’ s literature before
installing the equipment.
Grounding the System
FIRE, EXPLOSION, AND ELECTRIC
SHOCK HAZARD
Proper electrical grounding of every part
of your system is essential. Read the
warning section, FIRE, EXPLOSION,
AND ELECTRIC SHOCK HAZARD , on
page 4 and follow the grounding
instructions below and in the Graco Shot
Foam System manual. All electrical wir -
ing must be done by trained and quali -
fied personnel.
WARNING
1. Foam dispense gun: connect the electrical cable
(A), supplied with the Graco Shot Foam System,
to the receptacle (2b) under the shield (51). See
Fig. 1.
T o assure proper grounding, do not use a gun with
a damaged or improperly installed receptacle (2b).
The ground wire eyelet (N) must be securely fas -
tened to the gun cover (2a) as shown in Fig. 1.
See page 21 if the receptacle needs to be serv -
iced.
2. Pump: connect a ground wire and clamp to a true
earth ground as shown in your separate pump
manual.
3. Fluid hoses:
use only Graco heated hoses, which
are electrically conductive.
4. Air hoses: use only grounded air hoses.
5. Air compressor: follow the manufacturer ’ s recom -
mendations for grounding.
6. Object being sprayed: ground according to the
local code.
7. Fluid supply container: ground according to the
local code.
8. All solvent pails used when flushing: follow the
flushing procedure in the Graco Shot Foam
System manual.
Fig. 1 03156A
A
N2a
2b
51
03151A

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Installation
Connecting the Hoses
NOTE: The fitting that is necessary to connect the air
hose to the gun air inlet is part of the system installa -
tion and is not included with the gun.
1. Make sure that the piston rod safety (C) is locked
and the fluid manifold needle valves (3a) are
closed. See Fig. 2.
2. Install the fittings required to adapt the air hose to
the gun air inlet. The gun air inlet is 1/8 npt(f).
3. Connect the air hose (B) to the gun air inlet fit -
ting (F).
4.
Install the shield (51) over the electrical connector
and air inlet fitting as shown in Fig. 2. Secure the
shield with the screw (52).
CAUTION
The shield (51) must be installed and secured with
the screw (52) to ensure that the electrical and air
connections are protected from damage and that
the cover is properly secured to avoid leakage.
5. Connect the ISO hose (E) to the fluid manifold inlet
marked ISO. See Fig. 2. The ISO fitting (3d) is 1/4
npsm(f).
6.
Connect the RES hose (D) to the fluid manifold
inlet marked RES. The RES fitting (3c) is 1/2
JIC (m).
NOTE: The fluid manifold connection to the gun nozzle
head is keyed so that crossing materials at this con -
nection is not possible if hoses are attached to the cor -
rect manifold inlets.
The fluid manifold inlets are marked ISO and RES.
When connecting the Graco Shot Foam Heated
Hoses to the fluid manifold, make only ISO to ISO
and RES to RES connections. See Fig. 2. Cross -
ing fluid can damage the hoses and gun. Refer to
the Graco Shot Foam System manual.
CAUTION Fig. 2 03156A, 3168A
ED
B
RES
ISO
3c 3d
51
52
3a
1
1
Turn clockwise to close needle valve
C
F
The Solvent Flushing System
You need a solvent flushing system to clean the nozzle
head assembly . See the Graco Shot Foam System
manual for the flushing procedure.

7308-316
Operation
Piston Rod Safety Lock
WARNING
INJECTION AND HOT MA TERIAL
HAZARDS
T
o reduce the risk of serious injury from
fluid injection or contact with hot mate -
rial, lock the piston rod safety whenever you stop
dispensing.
The gun has a piston rod safety lock, which is a detent
device positioned across the neck of the gun, adjacent
to the main body of the gun. See Fig. 3.
T o lock the piston rod safety and make the gun inop -
erative, slide the safety detent fully to the left, as
shown in Fig. 3-- Locked . T o unlock the piston rod
safety and make the gun operative, slide the safety
detent fully to the right until the red mark is visible, as
shown in Fig. 3-- Unlocked.
Fig. 3 02675A
Piston Rod Safety
Unlocked
Piston Rod Safety
Locked
red mark
visible
TOP VIEW OF GUN
General Startup
INJECTION AND HOT MA TERIAL
HAZARDS
To reduce the risk of serious injury from
fluid
injection or contact with hot material:
DLock the piston rod safety whenever you stop
dispensing.
DW
ear the appropriate protective clothing,
gloves, eyewear , facemask, and respirator .
WARNING
Follow the startup procedure in the Graco Shot Foam
System manual. A general startup procedure is pro -
vided below , however , each application will dif fer in
some way . Always follow the specific recommenda -
tions of the system and material suppliers.
1. Adjust the fluid temperature.
Read the Graco Shot Foam System manual and
material supplier recommendations for the best
hose control temperature settings for your specific
application. Typical foams are designed to spray at
150_F (65_C).
2. Adjust the pump outlet pressure.
Read the Graco Shot Foam System manual and
material supplier recommendations. T ypical pres -
sures are 400 to 500 psi (28 to 35 bar).
WARNING
COMPONENT RUPTURE HAZARD
Do not exceed the maximum working
pressure of the lowest rated system
component. This equipment has a 950
psi (66 bar) maximum working fluid pressure
and a 180 psi (12 bar) maximum working air
pressure . Exceeding these pressures can cause
component rupture, which can result in serious in -
jury or property damage.
Continued on the next page.

 
Operation
General Startup (continued)
3. Allow the fluid to heat thoroughly,
as recommended by the Graco Shot Foam System
manual and the material supplier . If the gun has
not been operated for 15 minutes or more, even if
the material has been kept heated, you may need
to dispense several shots to bring thoroughly
warmed material to the gun.
4. Dispense the foam.
Follow the instructions in the Graco Shot Foam
System manual.
CAUTION
When opening the fluid manifold needle valves,
open the RES side first, then open the ISO side.
Be sure both needle valves are fully open before
triggering the gun. This will help avoid material
cross-over.
5.
IMPORTANT: Keep the tip of the nozzle and
the nozzle head free of foam buildup.
INJECTION AND HOT MA TERIAL
HAZARDS
To reduce the risk of serious injury from
fluid
injection or contact with hot material:
DLock the piston rod safety before wiping the
nozzle tip and nozzle head clean.
D Keep the tip of the nozzle and the nozzle head
free of foam buildup. Foam buildup on the
nozzle can cause foam shots to be misdirected,
which can splash foam in the eyes or on the
skin.
WARNING
a. Between sets of foam shots, lock the piston
rod safety , and wipe the nozzle (5) and nozzle
head (4) with a dry cloth. See Fig. 4. T o im -
prove nozzle life, use a cloth dampened with
gun cleaning solution when cleaning the gun.
b. Periodically , the foam buildup may need to be
scraped of f the front nozzle area (X) with a
sharp knife or razor blade. See Fig. 4. Be sure
to keep the blade flat when sliding it across the
nozzle (5) tip surface; do not insert the blade
into the nozzle (5) tip.
CAUTION
Do not insert the knife/razor blade into the nozzle
(5) tip while cleaning the front nozzle area (X) as it
may gouge the nozzle or needle. Be careful not to
damage the exposed portions of the needle,
nozzle, and nozzle head.
Fig. 4
4
5
X


9308-316
Maintenance
Lubricating Parts
Two types of grease are used with this gun:
D ISO grease (part no. 106–565) is packed inside the
nozzle retainer (5b--refer to Fig. 5) reservoir to
keep the needle wetted. The ISO grease is used
because it is compatible with the isocyanate
material.
D
Lithium grease is used to lubricate the o-rings.
NOTE: During operation, a small amount of ISO
grease (which is gray colored) may leak out the back
of the end cap (5a) and build up around the needle.
Wipe this residue off occasionally to keep the quick-
disconnect clean.
CAUTION
If a yellow/brown residue is leaking out the back of
the end cap (5a), it indicates that foam material is
leaking past the forward seal. The foam may
adhere and eventually harden on the quick-discon -
nect. If foam is leaking, repair or replace the
needle/nozzle assembly to avoid seizure of the
quick-disconnect.
Needle/Nozzle Assembly Maintenance
The needle/nozzle assembly needs to be repaired or
replaced when one or more of the following conditions
exist:
D
One or both foam component materials leak from
the nozzle tip. If this happens, repair or replace the
needle/nozzle assembly immediately to avoid
cross-over.
D
The needle sticks in the closed position for a
moment before opening. The foam gun may recoil
slightly when this happens. Once detected, this
condition will progressively worsen until the needle
freezes completely .
D ISO and RES pressures begin to dif fer , indicating a
partial clog in the impinger port of the higher pres -
sure component. If pressures differ by 250 psi (17.5
bar) or more, repair or replace the needle/nozzle
assembly immediately to avoid cross-over .
D
Foam material is leaking out the back of the end
cap (5a) or is visible in the quick-disconnect groove.
Repair or replace the needle/nozzle assembly to
avoid seizure of the quick-disconnect.
Nozzle life will vary slightly , depending on the applica -
tion. Once the normal life of the nozzle is established
with your system, it is recommended that you set a
maintenance schedule to repair or replace the needle/
nozzle assembly just before the expected failure to
avoid the downtime it might cause.
It is recommended that you pre-build the nozzle head
assemblies (4 and 5) so they are available for quick
replacement.
Fig. 5 
4
5b
5a
5
Continued on the next page.

 
Maintenance
Needle/Nozzle Assembly Repair or
Replacement
INJECTION AND HOT MA TERIAL
HAZARDS
To reduce the risk of serious injury from
fluid
injection or contact with hot material:
DLock the piston rod safety whenever you stop
dispensing.
D
Close the fluid manifold needle valves
completely with the nut driver provided before
servicing the gun; this will isolate the fluid pres -
sure in the manifold and fluid hose.
WARNING
The needle/nozzle assembly (5) can be replaced as
one complete assembly , part no. 236–310. See Fig. 6.
Fig. 6 04718
5
Or it can be repaired with the Needle/Nozzle Kit (5d),
part no. 236–287. See Fig. 7.
Fig. 7 04719
5d
5e
1
1Wiper
seal (5e) is included with the needle/nozzle kit (5d)
Remove the Needle/Nozzle Assembly:
1. Lock the piston rod safety (C) and close the fluid
manifold needle valves (3a) with the nut driver
(49). See Fig. 8.
03184A
3a
1
1
Turn clockwise to close needle valve.
T urn counterclockwise to open needle valve.
49
C
Fig. 8
2. Loosen the one fluid manifold screw (3b) with the
3/16” hex wrench (47), and disconnect the man -
ifold (3) from the nozzle head (4). See Fig. 9.
3. Clean out both manifold ports; be careful not to
mix material while cleaning.
4. Loosen the two nozzle head screws (4e).
47
3b
4
3
4e
Fig. 9 03153A

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Maintenance
Needle/Nozzle Assembly Repair or
Replacement (continued)
5. Insert the quick-disconnect hook (50) into the slot
on the gun body neck. Hook the quick-disconnect
sleeve, and pull it back toward the rear of the gun
while you remove the nozzle head assembly (4, 5).
See Fig. 10.
NOTE: Y ou must use the quick-disconnect tool to
disconnect the needle from the piston rod before
you can remove the nozzle head assembly .
6.
Remove and retain the thermal spacer (16). See
Fig. 1 1.
7. T
ake the nozzle head assembly (4, 5) to a flushing
station for cleaning. See the flushing procedure in
the Graco Shot Foam System manual for specific
flushing instructions.
NOTE: The gun body can remain on the produc -
tion line if no foam buildup is visible on the piston.
If there is buildup, remove the gun from the pro -
duction line, as instructed on page 18, and clean it.
8. Remove the nozzle retainer (5b). See Fig. 12.
9. Press the needle/nozzle assembly (5) out of the
nozzle head (4). Clean the nozzle head thoroughly .
Be careful not to damage any sealing surfaces.
10. If you are replacing the complete needle/nozzle
assembly (5), continue with step 22, page 13. If
you are using the needle/nozzle kit to repair the
needle/nozzle assembly, continued with step 1 1 on
page 12.
03285A
50
4, 5
Fig. 10
Fig. 11
4, 5
16 03155
1
02677
4
5b
5a
5
Fig. 12
Continued on the next page.

 
Maintenance
Needle/Nozzle Assembly Repair or
Replacement (continued)
Repairing the Needle/Nozzle Assembly
11. Pull the nozzle retainer (5b) with the end cap (5a)
of f of the needle/nozzle (5d). Refer to Fig. 13.
12. Unscrew the end cap (5a) from the nozzle retainer
(5b).
13.
Remove the sleeve seal (5c) from the end cap
(5a). Remove the wiper seal (5e) from the end cap
with a pick.
14. Discard the old needle/nozzle set (5d) and the old
wiper seal (5e). Clean the nozzle retainer (5b), end
cap (5a), and sleeve seal (5c) thoroughly with gun
cleaning solution and a pick, and retain them for
reassembly.
NOTE: If the parts are worn or cannot be cleaned as
needed, replace them with new parts.
Fig. 13 03879
5d
5b
5a
5c
5e
1
1Wiper
seal (5e) is included with the needle/nozzle kit (5d)
15. Insert the seal installation tool (53) into the wiper
seal (5e) that is included with the kit. Orientate the
seal and tool as shown in Fig. 14.
16. Press the wiper seal (5e) into the end cap (5a) with
the seal installation tool (53), then remove the tool.
17. Press the sleeve seal (5c) into the end cap (5a).
See Fig. 15.
18. Slide the nozzle retainer (5b) onto the needle/
nozzle (5d).
19. Using a graduated syringe containing ISO grease,
fill the reservoir of the nozzle retainer (5b) with 1.4
to 1.5 cc of ISO grease (Graco part no. 106–565) .
20. Slide the installation bullet (54) over the needle to
protect the wiper seal (5e) as shown in Fig. 15.
Then slide the end cap (5a) onto the needle and
remove the installation bullet.
21. T ighten the end cap (5a) securely into the nozzle
retainer (5b) (about 1/4 turn past hand-tight). Be
careful not to damage the nozzle retainer when
tightening the end cap.
CAUTION
Do not tighten the needle nozzle assembly into the
nozzle head before tightening the end cap (5a) into
the nozzle retainer (5b) as that could cause the
grease to be over-pressurized and result in prema -
ture leaking.
Fig. 14 03878
5e 535a
Fig. 15 03877
5b 1
1Fill
with 1.4 to 1.5 cc of ISO grease
T ighten securely (about 1/4 turn past hand-tight)
54
5a 5c
5d
2
2


Maintenance
Needle/Nozzle Assembly Repair or
Replacement (continued)
Check V alve Maintenance
The nozzle head check valve needs periodic mainte -
nance as the foam material can build up in this area
and cause pressure variations. In extreme cases, ma -
terial cross-over may occur . Service the check valve
as instructed below whenever you repair or replace a
needle/nozzle assembly .
NOTE: A Repair Kit, part no. 237–257, is available.
See page 33.
22. Remove the plastic seat (4a) and o-ring (4d) from
each check valve with a pick. See Fig. 16.
23. Remove the ball (4b) and spring (4c) from each
check valve.
24. Clean all the parts thoroughly , including the nozzle
housing bore (U). Replace the check valve parts
as needed.
25. Install the spring (4c) and ball (4b) into the nozzle
housing.
26.
Install the o-ring (4d) onto the seat (4a). Press the
seat into the nozzle housing until it is flush with the
top of the bore (U).
Install the Needle/Nozzle Assembly and
Reassemble the Gun
27. Push the needle/nozzle assembly (5) into the
nozzle head (4). See Fig. 17. T orque the nozzle
retainer (5b) to 15 ft-lb. (20.25 N Sm); do not turn
the end cap (5a) while tightening the retainer .
28.
Install the thermal spacer (16) against the back of
the nozzle head (4). See Fig. 18.
29. Slide the nozzle head assembly (4, 5) and thermal
spacer (16) onto the gun body (1). Align the needle
with the quick-disconnect hole and push it in. Y ou
should feel when the needle sets into the quick-
disconnect.
Fig. 16 03162
4a
4b
4c
4d
U
Fig. 17 02677
5b
5a
5
1
1Torque
nozzle retainer (5b) to 15 ft-lb. (20.25 N Sm).
4
Fig. 18
4, 5
16
03155
1
Continued on the next page.

14 308-316
Maintenance
Needle/Nozzle Assembly Repair or
Replacement (continued)
30. Tighten the two nozzle head screws (4e) to 4.5 to
6.5 ft-lb (6.1 to 8.8 N S m). See Fig. 19.
INJECTION AND HOT MA TERIAL
HAZARDS
T
o avoid serious injury and property
damage, be sure the two nozzle head
screws (4e) are properly tightened to 4.5 to 6.5 ft-lb
(6.1 to 8.8 N S m). Failure to tighten the screws will
cause the gun to fail open.
WARNING
31. Inspect the fluid manifold (3) ports to make sure
they are clean. Install the fluid manifold (3) onto
the nozzle head (4). T orque the manifold screw
(3b) to 40 in-lb (4.52 N Sm).
32.
Open the fluid manifold needle valve (3a) for the
RES side first, then open the ISO side. See
Fig. 20.
CAUTION
When opening the fluid manifold needle valves
(3a), open the RES side first, then open the ISO
side. Be sure both the needle valves are fully open
before triggering the gun. This will help avoid
material cross-over .
Air V alve Piston and Spool Maintenance
Lubricate the air valve piston and spool o-rings with
lithium grease after approximately 100,000 cycles. See
pages 22 to 25 to disassemble and service the piston
and spool.
INJECTION AND HOT MA TERIAL
HAZARDS
The piston and spool o-rings must be
lubricated approximately every 100,000
cycles to reduce the risk of piston failure. If the fail -
ure occurs when the gun is triggered, fluid may
continue to flow , which could cause serious injury
or property damage.
WARNING
47
3b
4
3
4e
1
2
Fig. 19
1
2
03153A
Torque manifold screw (3b) to 40 in-lb (4.52 N Sm).
Torque
nozzle head screws (4e) to 4.5 to 6.5 ft-lb (6.1 to 8.8 N Sm)
03184A
1Turn
clockwise to close needle valve.
T urn counterclockwise to open needle valve.
Fig. 20
3a
1
49

15308-316
Troubleshooting
INJECTION AND HOT MA TERIAL HAZARDS
T o reduce the risk of serious injury from fluid injection or contact with hot material:
D Lock the piston rod safety whenever you stop dispensing.
D Close the fluid manifold needle valves completely with the nut driver provided before servicing the gun; this
will isolate the fluid pressure in the manifold and fluid hose.
D If service or maintenance requires removing the gun from the production line, follow the procedure on page
18 to remove the gun.
WARNING
PROBLEM CAUSE SOLUTION
Air leaks:
1. Between gun body and cover ,
when gun is triggered or not
triggered
1. O-ring (29) is missing or damaged 1. Install or replace o-ring. See Parts,
page 32.
2. Between gun body and cover ,
when gun is triggered
2. O-ring (43) is missing or damaged 2. Install or replace o-ring. See Parts,
page 32.
3. Through exhaust holes:
a. When gun is not triggered
b. When gun is triggered or not
triggered
c.
When gun is triggered
3. a.
Solenoid (2f) failed
Rear spool o-ring (7b) failed
Front piston separator o-ring (32)
failed
b. Middle spool o-ring (7b) failed
Front piston o-ring (33) failed
c. Rear piston separator o-ring (32)
failed
Front spool o-ring (7b) failed
3. a.
Replace solenoid. See page 20.
Lubricate or replace o-ring.
See page 25.
Lubricate or replace o-ring.
See page 22.
b. Lubricate or replace o-ring.
See page 25.
Lubricate or replace o-ring.
See page 22.
c. Lubricate or replace o-ring.
See page 22.
Lubricate or replace o-ring.
See page 25.
4. Through safety lock area, when
gun is triggered
4. Gun body o-ring (25) and back-up
ring (24) failed
4. Lubricate or replace o-ring and back-
up ring. See page 22.
Fluid leaks:
1. Between nozzle & needle, hous -
ing or packing
1. W orn nozzle or seals 1. Repair or replace needle/nozzle
assembly (5). See page 10.
2. Between nozzle & housing 2. Foam buildup on nozzle sealing
surfaces in nozzle head (4)
2. Clean or replace nozzle head.
See page 10.
Gun operates slowly when it is
triggered 1.
Inbound air pressure is too low 1. Increase air pressure, but do not
exceed 180 psi (12 bar) Maximum
Working Air Pressure.
2. Air valve is leaking air 2. See Air leaks section, above.
3. Needle sticking due to foam buildup
as nozzle wears 3.
Repair or replace needle/nozzle
assembly (5). See page 10.
4. Air valve spool or piston o-rings dry ,
causing drag
4. Lubricate or replace o-rings. See
pages 22 and 25.

 
Troubleshooting
PROBLEM CAUSE SOLUTION
Gun is slow to de-trigger. NOTE:
Over-shoot
in excess of preset toler -
ance may cause system to lock-out.
1. Inbound air pressure is too high 1. Decrease air pressure, do not exceed
180 psi (12 bar) Maximum W orking
Air Pressure.
yy
2. Solenoid (2f) failed 2. Replace solenoid. See page 20.
3. Spool spring (7a) is broken or worn 3. Replace spring. See page 25.
Gun fails closed 1. Safety lock is engaged 1. Disengage safety lock.
2. Air pressure loss to gun 2. Check air line connection and pres -
sure source.
3. Electrical power loss to gun 3. Check electrical connection and
power source.
4. Needle/nozzle assembly is frozen 4. Repair or replace needle/nozzle
assembly (5). See page 10.
5. Solenoid (2f) failed 5. Replace solenoid. See page 20.
6. Inbound air pressure is too low 6. Increase air pressure, but do not
exceed 180 psi (12 bar) Maximum
Working Air Pressure.
7. T riggering device failed 7. Replace trigger switch (9). See page
27.
8. Quick-disconnect is not properly
connected 8.
Clean or replace piston rod/quick-
disconnect (6). See page 23.
9. Needle is not properly installed in gun 9. Check that needle is positioned flush
in nozzle. Correct as needed.
Gun fails open 1. Spool spring (7a) is missing or bro -
ken 1.
Install or replace spring. See page
25.
2. Needle/nozzle assembly is frozen 2. Repair or replace needle/nozzle
assembly (5). See page 10.
3. Solenoid (2f) failed 3. Replace solenoid. See page 20.
4. Air pressure to gun is too high 4. Decrease air pressure, do not exceed
180 psi (12 bar) Maximum W orking
Air Pressure.
5. Rear spool o-ring (7b) failed 7. Replace o-ring. See page 25.

17308-316
Service
Lubricating Parts
Two types of grease are used with this gun:
D ISO grease (part no. 106–565) is packed inside the
nozzle retainer reservoir as it is compatible with the
isocyanate material.
D Lithium grease is used to lubricate o-rings.
Tools
The following tools are supplied with the gun
(see Fig. 21):
Ref. Description
47 3/16” hex T -handle wrench
48 9/64” hex T -handle wrench
49 Nut driver
50 Quick-disconnect hook
53 Seal Installation T ool
54
Installation Bullet
In addition, you will need the tools listed below (see
Fig. 22 and 23). See Accessories , page 34 to order
items AA to CC. Items DD to HH are standard tools
you must provide.
Ref. Description
AA Spool removal tool, part no. 189–553
BB Piston removal tool, part no. 189–555
CC Air valve hook, part no. 178–583
DD Small adjustable wrench
EE 7/16” open end wrench
FF Screw driver
GG 5/64” allen wrench
HH 9/16” thin wall socket wrench
Fig. 21 
49
47
Tools Included with the Gun
50
48
54
53

BB CCAA
Accessories
Fig. 22
Fig. 23 
DD EE
FF
Standard T ools
HH
GG

 
Service
Removing t h e G u n f ro m t h e P roductio n L ine
NOTE: The gun must be removed from the production
line for most service procedures.
See page 33 to order repair kits.
INJECTION AND HOT MA TERIAL
HAZARDS
To reduce the risk of serious injury from
fluid
injection or contact with hot material:
DLock the piston rod safety whenever you stop
dispensing.
D
Close the fluid manifold needle valves
completely with the nut driver provided before
servicing the gun; this will isolate the fluid pres -
sure in the manifold and fluid hose.
WARNING
1. Lock the piston rod safety (C) and close the fluid
manifold needle valves (3a) with the nut driver
(49). See Fig. 24.
2. T urn of f the air supply to the gun and bleed of f the
air pressure.
3. Remove the screw (52) and shield (51). Set them
aside to reinstall when the gun is installed back on
the production line.
4. Remove the air hose (B) from the gun.
5. Remove the electric cable (A) from the gun.
NOTE: Y ou have two options for disconnecting the gun
from the fluid supply:
D Disconnect the nozzle head assembly from the gun
and leave it connected to the manifold, then re -
move the gun body from the production line. Fluid
pressure will be isolated in the nozzle head, man -
ifold, and fluid hose.
D Disconnect the manifold from the nozzle head and
remove the gun body and nozzle head assembly
from the production line. Fluid pressure will be iso -
lated in the manifold and fluid hose. This is the pro -
cedure that follows.
6. T o disconnect the gun body and nozzle head
assembly from the production line, loosen the one
fluid manifold screw (3b) with the wrench (47), and
disconnect the manifold (3) from the nozzle head
(4). See Fig. 25.
7. Loosen the two nozzle head screws (4e).
03156A
A
51
52
Fig. 24
1
1
Turn clockwise to close needle valve. T urn counterclockwise
to open needle valve.
C
3a
B
47
3b
4
3
4e
Fig. 25
03838

19308-316
Service
Removing the Gun from the Production
Line (continued)
8. Insert the quick-disconnect hook (50) into the slot
on the gun body neck. Hook the quick-disconnect
sleeve, and pull it back toward the rear of the gun
while you remove the nozzle head assembly (4, 5).
See Fig. 26.
NOTE: Y ou must use the quick-disconnect tool to
disconnect the needle from the piston rod before
you can remove the nozzle head assembly .
Fig. 26 03154A
50
4, 5
9. Remove and retain the thermal spacer (16). See
Fig. 27.
10. T ake the nozzle head assembly (4, 5) to a flushing
station for cleaning as needed. See the flushing
procedure in the Graco Shot Foam System
manual.
11.
The gun body is now separated and ready for ser -
vice. Follow the service procedures on the follow -
ing pages of this manual.
Fig. 27
4, 5
16 03155
1

 
Service
Solenoid V alve
Slow operation of the gun, failure to operate, or air
leakage through the exhaust holes when the gun is
untriggered may indicate a solenoid valve failure. T o
replace the solenoid, follow the procedure below .
NOTE: A Repair Kit, part no. 237–621, is available.
See page 33.
1. Remove the gun from the production line as
instructed on page 18.
2. Remove the screws (39) and the cover (2a) from
the back of the gun. See Fig. 28.
NOTE: Removing the cover will unplug the trigger
switch electrical connector (Q) and may cause the
spool return spring (7a) to fall out of place.
3. Disconnect the solenoid connectors (J). See
Fig. 29.
4. Insert the straight end of the air valve hook
(CC--shown in Fig. 21) into the base of the sole
-
noid valve (2f) and unscrew it from the cover (2a).
5. Install a new solenoid valve (2f). T ighten it with the
air valve hook (CC).
6. Loosen the solenoid valve ring (L) by hand and
adjust the orientation of the contacts (K) so they
line up with the center of the cover protrusion (M),
as shown in Fig. 29. Only loosen the ring, do not
disassemble the solenoid valve.
CAUTION
Do not disassemble the solenoid valve as the
internal spider spring has been custom-shimmed
for each valve to provide the required performance.
7. After the contacts are orientated, tighten the sole -
noid valve ring (L).
8. Connect the solenoid connectors (J). See Fig. 28.
NOTE: One connector lead is longer for easier
connection to the farthest contact.
9. Assemble the gun as instructed on page 28 if no
further maintenance or service is required.
Fig. 28 03157A
39
J
2a
Q
7a
Fig. 29
KL
M
J
2f
2a
03807