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.

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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
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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.

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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