Clemco 24189 User manual

POWER GUN
SUCTION ABRASIVE BLAST TOOLS
O. M. 24189
DATE OF ISSUE: 02/06
REVISION: C, 06/18
© 2018 CLEMCO INDUSTRIES CORP.
One Cable Car Dr.
Washington, MO 63090
Phone [phone]
Fax [phone]
Email: [email protected]
www.clemcoindustries.com
Do not use this equipment
before READING this
MANUAL and
UNDERSTANDING its
contents.
These WARNINGS are
included for the health
and safety of the operator
and those in the
immediate vicinity. Failure
to read and understand
these warnings can result
in injury or death.
Electronic files include a
Preface containing the
same important
information as in the
orange cover.
WARNING

POWER GUN SUCTION BLAST TOOLS Page 1
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
1.0 INTRODUCTION
1.1 Scope of Manual
1.1.1 This manual covers installation, operation,
maintenance, and replacement parts of Clemco Power
Gun suction blast tools.
1.1.2 All personnel involved with abrasive blasting
must be aware of the hazards associated with abrasive
blasting. The Clemco booklet Abrasive Blasting Safety
Practicesis included with every blast machine; it
contains important safety information about abrasive
blasting that may not be included in equipment operation
manuals. To request additional copies, email
[email protected].
1.2 Safety Alerts
1.2.1 Clemco uses safety alert signal words, based on
ANSI Z535.4-2011, to alert the user of a potentially
hazardous situation that may be encountered while
operating this equipment. ANSI's definitions of the signal
words are as follows:
This is the safety alert symbol. It is
used to alert you to potential physical
injury hazards. Obey all safety
messages that follow this symbol to
avoid possible injury or death.
NOTICE
Notice indicates information that is considered
important, but not hazard-related, if not
avoided, could result in property damage.
CAUTION
Caution indicates a hazardous situation that, if
not avoided, could result in minor or moderate
injury.
WARNING
Warning indicates a hazardous situation that, if
not avoided, could result in death or serious
injury.
DANGER
Danger indicates a hazardous situation that, if
not avoided, will result in death or serious injury.
1.3 Table of Contents
INTRODUCTION ........................................................ 1.0
Scope of Manual ..................................................... 1.1
Safety Alerts ............................................................1.2
Table of Contents ....................................................1.3
General Description ................................................ 1.4
Components and Operating Principles ................ 1.5
COMPRESSED AIR and ABRASIVES .................... 2.0
Compressed Air Requirements ..............................2.1
Abrasives ................................................................. 2.2
SETUP ........................................................................ 3.0
General Setup .........................................................3.1
Water Connection (H2O Model) ..........................3.2
OPERATION .............................................................. 4.0
Start Compressed-Air Supply ................................. 4.1
Operator Safety Equipment .................................... 4.2
Insert Lance into Optional Hopper .........................4.3
Insert Lance into Bagged Abrasive ........................ 4.4
Dry Blasting ............................................................. 4.5
Wetblasting, H2O Model Only ................................ 4.6
Shutdown ................................................................. 4.7
ADJUSTMENTS ........................................................ 5.0
Blast Pressure .........................................................5.1
Positioning of Hose and Gun ..................................5.2
Water Flow, H2O Model Only ................................5.3
Air Induction Valve (stops abrasive flow) ...............5.4
MAINTENANCE ......................................................... 6.0
Removing Nozzle and Air Jet ..............................6.1
Nozzle .................................................................6.2
Air Jet, Dry Blast .................................................6.3
Air Jet, H2O Model (wetblast)..............................6.4
CONVERTING DRY BLAST to H2O WETBLAST .7.0
TROUBLESHOOTING .............................................. 8.0
No Abrasive Flow ................................................8.1
Plugged Nozzle ...................................................8.2
Abrasive Bridging ................................................8.3
Neither Air Nor Abrasive Comes Out Nozzle ......8.4
Air Leaks from Gun After Trigger is Released ....8.5
Abrasive Surge ....................................................8.6
Poor Suction in Material Hose ............................8.7
Blow-Back Through Material Hose .....................8.8
Air Leak at Gun and Trigger Assembly .................8.9
ACCESSORIES AND REPLACEMENT PARTS ....9.0
Optional Accessories ..............................................9.1
Power Gun Systems ............................................... 9.2
Blast Gun Assembly, dry blast ............................... 9.3
System Replacement Parts ....................................9.4
Blast Gun Assembly, H2O Model ......................... 9.5
Gun and Trigger Assembly ..................................... 9.6

POWER GUN SUCTION BLAST TOOLS Page 2
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
Figure 1
1.4 General Description
1.4.1 This manual covers two Power Gun models.
Both models are available with or without the cart and 3
cuft hopper.
Conventional Power Gun: limited to dry blasting only.
Power Gun Model H2O: can be used for dry blasting and
has water connections to add water into the blast
stream.
1.4.2 Power Guns are ideally suited for light-duty,
small, and touchup blasting jobs. The performance of the
Power Gun approaches that of a small pressure system,
but does not require a pressure vessel nor does it require
the setup time and maintenance of a pressure system.
1.5 Components and Operating Principles
1.5.1 Components
1.5.1.1 Components of the Power Guns are shown in
Figure 1, the gun assembly is shown in Figure 2, and the
additional parts for the Model H2O wetblast gun
assembly are shown in Figure 3.
1.5.2 Operating Principles
1.5.2.1 When compressed air is supplied to the gun and
the trigger is pulled, air flows through the gun, creating a
partial vacuum in the material hose. As a result, abrasive
is drawn into the lance, through the material hose, and
into the mixing chamber. Abrasive mixes with the air
stream within the mixing chamber and is propelled
through the nozzle onto the surface being blasted.
Figure 2
1.5.2.2 Besides being an effective dry blaster, additional
parts provided with the H2O model (shown in the insert
in Figure 1 and Figure 3) include a water jacket and
hose, which attaches to a municipal water supply
(faucet). When the water supply is turned ON, the water
valve allows the operator to turn water ON and OFF and
regulate the amount of water added into the mixing
chamber and blast stream. Water entering the blast
Material Hose
Air Hose
Lance
Abrasive Inlet Holes
Air-Intake Holes
Safety Lock Pin
Connecting Collar
Air-Hose
Coupling Water Hose
Water Valve Ai
r
-Induction Valve
Callouts within broken lines are additional
i
te
m
s
in
c
l
uded
wi
t
h H2
O
m
od
e
l.
Mixing Chamber
Some items rotated for clarity.
Nozzle Mixing Chamber
H2O Model
Water Jacket
3/4" Water Connecto
r
Gun Assembly
Optional Cart with
3 Cuft Hopper
Blast-Pressure
Control Knob
Air Hose
Material Hose
Nozzle
Mixing Chamber
Gun Assembly
Trigger
Dry Blast Gun Assembly

POWER GUN SUCTION BLAST TOOLS Page 3
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
stream is combined with air and abrasive before exiting
the nozzle.
Additional controls on the H2O mixing chamber, allow
the user to control all of the following from the blast gun:
1. Dry blasting with air and abrasive
2. Wet blasting with air, abrasive, and water
3. Wash down with air and water
4. Blow down with air only
Figure 3
1.5.3 Hose Limitations
1.5.3.1 Material Hose: Standard Power Gun assemblies
come with 16 feet or 30 feet of material hose. The
maximum recommended length is 30 feet, provided
adequate pressure is maintained at the gun and the
nozzle and jet are maintained as noted in Section 6.0.
1.5.3.2 Air Hose: Standard Power Gun assemblies come
with 16 feet or 30 feet of air hose. Longer length of bulk
air hose may be ordered or a 3/4" ID or larger extension
hose may be added, provided adequate pressure is
maintained at the gun. Refer to Section 2.1.
2.0 COMPRESSED-AIR and ABRASIVES
2.1 Compressed Air Requirements
2.1.1 The table in Figure 4 shows approximate air
consumption (cfm) at various pressures (psi) for the
Power Gun alone. Additional air is needed for a
supplied-air respirator, plus other air tools that may be in
use at the same time as the Power Gun. The table
shows air consumption; it does not show the
recommended compressor size. Check with a
compressor supplier for compressor recommendations
based on total compressed-air requirements.
2.1.2 For most applications, the compressor should
be large enough to maintain 80-100 psi under working
conditions. Delicate work may require lower pressure,
and tough applications may require higher pressure.
2.1.3 The air-jet orifice is 1/4" ID and the nozzle orifice
is 1/2" ID.
Air consumption in cfm
PSI 40 50 60 70 80 90 100 120 140
CFM 49 58 67 76 85 94 103 121 138
Figure 4
2.2 Abrasives
2.2.1 Abrasive Size: The Power Gun utilizes common
abrasives that are 12 mesh and finer. Limited air supply,
low blast pressure, or heavy abrasive may limit abrasive
to smaller sizes.
2.2.2 Use only abrasives specifically manufactured for
blast cleaning and that are compatible with the surface
being blasted. Abrasive produced for other applications
may be inconsistent in size and shape, and contain
particles that could jam the suction gun, and produce an
unsatisfactory finish.
WARNING
All abrasives produce hazardous dust. Obtain a
safety data sheet (SDS) for the blast abrasive
being used and make sure it is available for the
operator to read and understand. Failure to use
appropriate respiratory equipment can result in
injury or death. 
H20-Blast Gun Assembly
Air Hose
Material Hose
Nozzle Mixing Chamber
Gun Assembly
3/4" Female Water
Hose Connection
Water Valve
Water Hose
Water Jacket
Air Induction
Valve

POWER GUN SUCTION BLAST TOOLS Page 4
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
3.0 SETUP
3.1 General Setup
3.1.1 An air filter is recommended in the air supply to
remove condensed moisture from the air line.
3.1.2 Connect the Power Gun’s air hose to a 3/4” or
larger air supply line. An isolation valve is required at the
air source to enable depressurization.
3.1.3 Secure all compressed-air supply hose
connections with safety lock pins and safety cables to
prevent accidental disconnection. Lock pins and safety
cables are listed in Section 9.1.
WARNING
Hose disconnection while under pressure can
cause serious injury or death. Use safety lock
pins or safety wire to lock twist-on claw type
couplings together and prevent accidental
separation, and safety cables to prevent hose
from whipping should separation occur.
3.1.4 Make sure the setscrews securing the nozzle,
jet, and gun assembly are tight.
3.2 Water Connection (H2O Model), Figure 5
3.2.1 Connect the water hose to a water faucet.
3.2.2 Make sure the water valve is in the OFF
position, handle perpendicular to the valve.
Figure 5
3.2.3 Loosen the air-induction tensioning knob and
rotate the sleeve to close the induction port. Tighten the
knob to secure.
3.2.4 Connect the water hose to a faucet; use a
garden hose if additional hose is needed.
3.2.5 Open the faucet to supply water to the Power
Gun.
3.2.6 Begin dry blasting per Section 4.5. After dry
blasting adjustments are made, open the water valve as
needed to regulate water flow. Open the valve only
enough to water to suppress dust and prevent it from
being airborne.
4.0 OPERATION
NOTE: Unless noted otherwise, the sequence of
operation in Sections 4.1 through 4.4 may be done in
any order that is best suited for the application.
4.1 Start Compressed Air Supply
4.1.1 For onsite blasting, locate the compressor
upwind and away from the blasting operation.
4.1.2 Make sure that all compressed-air supply-hose
claw-type couplings are secure with safety lock pins and
safety cables to prevent accidental disconnection. Lock
pins and safety cables are listed in Section 9.1.
WARNING
Hose disconnection while under pressure can
cause serious injury or death. Use safety lock
pins and safety cables on all blast hose and air
hose coupling connections to help prevent
hose couplings from accidental disconnection.
4.1.3 Close the air-supply valve, start the compressor
and bring it up to operating temperature and pressure.
4.1.4 Slowly open the compressor air valve to
pressurize the air-supply line. Listen for noise that
indicates any open lines or leaks.
4.1.5 Do not allow anyone around the blasting area
who is not appropriately fitted with approved personal
protective equipment, per Section 4.2.
Air Induction Valve
Tensioning Knob
Water Valve
Shown fully Closed.
Water Connection
(Garden hose swivel)
Water Hose
Air Induction Port
Shown open.

POWER GUN SUCTION BLAST TOOLS Page 5
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
4.2 Operator Safety Equipment
WARNING
Before blasting, test the coating and substrate
for toxic materials (such as lead, other heavy
metals, or asbestos). These hazards require
special measures to protect the operators and
the environment.
Obtain a safety data sheet (SDS) for the blast
abrasive to identify hazardous substances.
Silica sand (crystalline) can cause silicosis,
lung cancer, and breathing problems in
exposed workers. Slag abrasives may contain
amounts of toxic metals such as arsenic,
beryllium, and cadmium. Any abrasive dust has
potential to cause lung disease.
Abrasive blasting operations can create high
levels of dust and noise. No dust is safe to
breathe. Abrasive blasting can produce harmful
dust. Failure to wear NIOSH-approved
respirators can result in serious lung disease or
death. The respirators must be properly-fitted
and maintained. Use only NIOSH-approved,
type-CE supplied-air respirators approved for
abrasive blasting.
During abrasive blasting, abrasive particles and
dust in the area around the blast machine and
blast nozzle become airborne. Everyone
working in the vicinity of abrasive blasting must
wear properly-maintained, NIOSH-approved,
respiratory protection and eye protection
appropriate for the job site hazards.
Loud noise generated by the use of
compressed air can cause hearing damage.
Everyone in the blasting area must wear
approved hearing protection.
It is the employer’s responsibility to train
employees to identify hazardous substances
and to provide suitable policies, procedures,
monitoring, recordkeeping, and personal
protective equipment.
4.2.1 Operators and anyone else exposed to the
hazards generated by abrasive blasting must wear
appropriate protective gear, including abrasive-resistant
clothing, leather gloves, eye and hearing protection, and
a NIOSH-approved Type CE supplied-air respirator.
4.2.2 Don all protective blasting attire outside the blast
area in a clean nonhazardous environment free of
contaminants, where the air is safe to breathe.
4.2.3 When finished blasting and after cleanup is
completed, remove the respirator and protective clothing
outside the blasting area in a clean environment free of
contaminants where the air is safe to breathe.
4.3 Insert Lance into Optional Hopper ‒Figure 6
4.3.1 The hopper and cart assembly must be placed
on a firm and level surface.
WARNING
The four-wheel cart rolls easily. It must remain
on sound, level ground. Do not place the cart
on scaffolding. Do not use on elevated surfaces
unless it is adequately anchored to prevent
movement. Failure can result in injury.
4.3.2 Make sure the cart’s rear support bar is down.
4.3.3 Remove any foreign material that may have
fallen inside the hopper.
4.3.4 Insert the lance about halfway into the
connecting collar, making sure the air-intake holes
remain outside the collar. Tighten the thumbscrew to
secure the lance.
Figure 6
4.3.5 Pour abrasive into the hopper; remove any
foreign material that may fall in. Do not fill the hopper to a
level that impairs easy maneuvering. If preferred, bagged
abrasive may be placed inside the hopper, and the lance
inserted into the bag as described in Section 4.4.
4.4 Insert Lance into Bagged Abrasive ‒Figure 7
4.4.1 Abrasive may be kept in the bag or poured into
a hopper, bucket, or similar container. Insert the lance
into the abrasive, making sure the upper (air-intake)
holes remain open and outside of the abrasive.
4.4.2 To use bagged abrasive, pierce the bag with the
pointed end of the lance. Insert the lance into the
Air-Intake
Holes
Rear
Support Bar Lance
Thumb
Screw

POWER GUN SUCTION BLAST TOOLS Page 6
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
abrasive. Using bagged abrasive requires repositioning
of the lance as the abrasive level drops.
SILICA
FREE
ABRASIVE
Figure 7
4.5 Dry Blasting
4.5.1 Don appropriate protective gear, including a
NIOSH-approved supplied-air respirator, abrasive
resistant clothing, leather gloves, and hearing protection
as required. Refer to Section 4.2.
4.5.2 Hold the gun approximately 6 inches from the
blast surface and squeeze the trigger. Adjust the stand-
off distance and angle for optimum performance.
4.5.3 Adjust blast pressure per Section 5.1.
4.5.4 To stop blasting release the trigger.
4.6 Wetblasting, H2O Model Only ‒Figure 8
4.6.1 Set up water connections per Section 3.2.
4.6.2 Close air-induction valve and begin dry blasting,
and set blast pressure per Section 4.5.
4.6.3 A moment after pulling the trigger, open the
water valve and adjust water flow per Section 5.3.
NOTICE
Open the water valve only after pulling the
trigger to begin blasting and always close it
before releasing the trigger to stop blasting.
Failure to have the water valve closed when the
trigger is released can allow water to flow into
the mixing chamber and material hose, causing
blockage from wet abrasive.
4.6.4 To stop blasting, close the water valve before
releasing the trigger. By not closing the water valve first
will allow water to flow into the mixing chamber and
material hose, causing blockage.
4.6.5 Wash Down: While blasting, loosen the air-
induction tensioning knob and rotate the sleeve to fully
open the induction port. This step stops abrasive flow
while air and water continue to flow through the nozzle
as long as the trigger is pulled.
NOTICE
Whenever using water, open the water valve
after pulling the trigger and close the water
valve before releasing the trigger. By having the
valve open when the trigger is not pulled can
allow water to flow into the mixing chamber and
material hose, causing blockage
4.6.6 Air Drying and Blow-off: After wash-down,
close the water valve and continue to hold the trigger.
Doing so will have air alone coming from the gun to
speed up the drying process. This process can also be
used to blow-off the blasted surface after dry blasting.
Figure 8
Air-Intake Holes
Lance
Some items rotated for clarity.
Trigger
Tensioning Knob
Water Valve
Handle shown fully open.
Water Valve
Handle shown fully Closed
Air Induction Valve
Shown Open.

POWER GUN SUCTION BLAST TOOLS Page 7
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
4.6.7 To stop blasting release the trigger.
4.7 Shutdown
4.7.1 When finished blasting, remove the lance from
the abrasive and shake abrasive from the material hose.
If conditions are safe to do so, pull the trigger to further
empty the hose.
4.7.2 Depressurize the air-supply line and shut down
the compressor.
4.7.3 For H2O models, shut off the water supply, drain
the water hose, and disconnect the hose.
5.0 ADJUSTMENTS
5.1 Blast Pressure ‒Figure 9
To reduce blast pressure rotate the control knob
clockwise. Reduced pressure is caused from reducing
the air volume through the gun. If greater control is
required, install a pressure regulator in the air-supply
line.
5.1.1 The control knob adjusts the force of air (blast
pressure) coming out the nozzle. Turning the knob
clockwise decreases the blasting force for delicate jobs,
and turning it counterclockwise increases the blast force
for tougher jobs.
Figure 9
5.2 Positioning of Hose and Gun ‒Figure 10
5.2.1 Whether the operator is left or right handed
could determine the most comfortable positioning of the
handle grip and material hose. To change the orientation
of the material hose with that of the handle grip, loosen
the three setscrews securing the mixing chamber to the
air-jet assembly.
Figure 10
5.2.2 Rotate the mixing chamber to obtain the most
comfortable position while holding the gun assembly and
material hose.
5.2.3 Make sure the jet is fully seated into the mixing
chamber before tightening the setscrews.
5.3 Water Flow (H2O Model only) ‒Figure 11
5.3.1 The water valve opens, regulates, and closes
water flow. Open only enough to suppress dust.
Figure 11
Turn knob counterclockwise
to increase blast pressure.
Setscrews
Mixing Chamber
Air Jet
Material Hose
Grip
Turn knob clockwise to
decrease blast pressure.
Some item rotated for clarity.
Water Valve
Shown fully closed. Trigger

POWER GUN SUCTION BLAST TOOLS Page 8
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
5.3.2 Open the water valve only after the pulling the
trigger to begin blasting and closed before releasing the
trigger to stop blasting.
NOTICE
Open the water valve only after pulling the
trigger to begin blasting and always close it
before releasing the trigger to stop blasting.
Failure to have the water valve closed when the
trigger is released can allow water to flow into
the mixing chamber and material hose, causing
blockage from wet abrasive.
5.4 Air-Induction Valve (stops abrasive flow)
Figure 12
5.4.1 Opening the air-induction valve disrupts the
vacuum used to pull abrasive into the mixing chamber
allowing air only (no abrasive) to exit the nozzle. This step
is used to blow off dry abrasive from the blast surface or
assist in drying a wet surface after wet blasting.
5.4.2 To stop abrasive flow, loosen the tensioning
knob and rotate the sleeve to fully open the induction
port. Close the valve to resume blasting.
Wash Down: If the water valve is open, air and water
continue to flow through the nozzle (as long as the
trigger is pulled) to wash off the blast surface. Refer to
Section 4.6.5.
Air Drying and Blow-Off: If the water valve is closed,
air continues to flow through the nozzle (as long as the
trigger is pulled) to blow-off dry surface or assist in dry
wet surfaces. Refer to Section 4.6.6.
Figure 12
6.0 MAINTENANCE
WARNING
Failure to observe the following procedure
before performing any maintenance or service
can cause serious injury or death from the
sudden release of compressed air.
Lockout and tagout the compressed-air
supply.
Bleed the air-supply line.
Periodically inspect the air jet, mixing chamber, nozzle,
and material hose for wear.
6.1 Removing Nozzle and Air Jet: There are no
threads on the mixing chamber; the jet and nozzle are
held onto the mixing chamber with three setscrews. Use
a 2.5 mm hex key to loosen the setscrews and while
twisting the nozzle and jet to loosen them, pull out to
remove them from the mixing chamber.
6.2 Nozzle: A new nozzle has a 1/2" ID orifice.
Replace the nozzle when its diameter has increased by
more than 1/16" (9/16” ID) or sooner if suction
diminishes noticeably.
6.3 Air Jet, Dry Blast
Refer to Section 6.4 to service the H2O air jet.
NOTE: Breakaway thread sealant is used on the
threads between the air jet and gun. The sealant
prevents parts from rotating out of alignment during
operation. When removing the jet, use a strap
wrench or similar wrench that will not damage the
shaded areas shown in Figure 13. If a wrench that
can damage the surface must be applied to remove
the jet, the jaws must be placed in the recess area as
shown in Figure 13.
6.3.1 Separate the air jet from the mixing chamber.
Use a 2.5 mm hex key to loosen the three setscrews
holding the jet to the mixing chamber and while twisting
the jet to loosen it, pull out to remove it from the chamber.
6.3.2 Replace the air jet when wear reaches the orifice
and affects the overall length. New air-jet orifices are 1/4"
ID and extend approximately 1-5/16" from the jet body.
NOTICE
When removing and installing an air jet, do not
put a wrench on the shaded areas shown in
Figure 13. The jet is a slip fit into the mixing
chamber; gouges will interfere with the fit.
Induction Valve Sleeve
Tensioning Knob
Air Induction Port
Shown open.

POWER GUN SUCTION BLAST TOOLS Page 9
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
6.3.3 The recommended method for removing the air
jet from the gun is with a strap wrench or similar tool that
will not damage the outside surface of the jet. If a
suitable wrench is not available use a pipe wrench or
slip-joint plier on the recess of the jet. If the jet is worn
and needs to be replaced, it does not matter if the
surfaces are damaged upon removal.
6.3.4 While the jet is removed, inspect the gun seat
for wear or damage. Replace as needed.
Dry-blast jet shown for reference.
Figure 13
6.3.5 Apply breakaway sealant such as Loctite 243 to
the air-jet threads and while pulling the gun’s trigger,
thread the jet fully into the gun until it bottoms-out. Snug
hand-tight is adequate. Refer to the sealant’s directions
and allow the sealant to cure before putting the gun into
service.
6.4. Air Jet, H2O Model
Refer to Section 6.3 to service the dry blast jet.
NOTICE
When handling the H2O gun be careful not to
apply force pressure to the water fittings and
valve. Applying force on the fittings can break
the water jacket fitting.
NOTE: Breakaway thread sealant is used on the
threads between the air jet and water jacket and
between the water jacket and gun. The sealant
prevents parts from rotating out of alignment during
operation. When removing the jet, use a strap
wrench or similar wrench that will not damage the
shaded areas shown in Figure 13.
6.4.1 Separate the air jet from the mixing chamber.
Use a 2.5 mm hex key to loosen the three setscrews
holding the jet to the mixing chamber and while twisting
the jet to loosen it, pull out to remove it from the chamber.
6.4.2 Replace the air jet when wear reaches the
orifice and affects the overall length. New air-jet orifices
are 1/4" ID and extend approximately 1-5/16" from the
jet body.
NOTICE
When removing and installing an air jet, do not
put a wrench on the shaded areas shown in
Figure 13. The jet is a slip fit into the mixing
chamber, gouges will interfere with the fit.
6.4.3 The recommended method for removing the air
jet from the water jacket is with a strap wrench or similar
tool that will not damage the outside surface of the jet. If
a suitable wrench is not available use a pipe wrench or
slip-joint plier on the recess of the jet. If the jet is worn
and needs to be replaced, it does not matter if the
surfaces are damaged upon removal.
6.4.4 Remove the water disc and washer from the
water jacket. Inspect all items and replace any that are
worn.
6.4.5 While the jet is removed, remove the water
jacket from the gun for inspection and inspect the gun
seat for wear or damage. Replace as needed.
6.4.6 Make sure the jet slots are facing away from the
water jacket, as shown in Figure 14, and insert the
washer and waterjet disc into the jacket.
Figure 14
6.4.7 Apply breakaway sealant to the first few
threads on the jet (excessive sealant could plug the
slots in the waterjet disc) and screw the jet into the
water jacket until it bottoms-out.
Mixing Chamber
Do not put a wrench on these surfaces.
If needed, apply wrench to recessed area.
Apply breakaway sealant to the
threads just before reassembly.
Waterjet Disc
Washer
H2O Air Jet
Water Jacket Disc slots face
toward the air jet.

POWER GUN SUCTION BLAST TOOLS Page 10
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
6.4.8 Apply breakaway sealant to the threads on the
water jacket. While pulling the gun’s trigger, thread the
jacket fully into the gun. Position the jacket’s water port
as noted in paragraph 7.3.2.
7.0 Converting Dry Blast to H2O Model Wetblast
7.1 The following instruction explains the conversion
of a dry blast power gun to a wetblast power gun Model
H2O. Components of the conversion kit are shown in
Figure 15.
Figure 15
7.2 Remove Dry Blast Components from the
Power Gun ‒Figure 16
7.2.1 Separate the mixing chamber from the air jet.
Use a 2.5 mm hex key to loosen the three setscrews
holding the mixing chamber to the jet. Then while twisting
the mixing chamber to loosen it, pull out to remove it from
the jet.
7.2.2 Use the same process to remove the nozzle
from the mixing chamber. Set the nozzle aside for reuse;
the mixing chamber will not be reused.
7.2.3 Pry or cut the hose clamp from the material hose
(a new clamp is provided with the kit) and remove the
hose from the mixing chamber. Set the hose aside for
reuse.
Figure 16
7.2.4 Remove the existing air jet from the gun
assembly. NOTE: Breakaway thread sealant is used
on the threads between the air jet and gun. The
sealant prevents parts from rotating out of
alignment during operation. The recommended
method for removing the air jet is with a strap wrench or
similar tool that will not damage the outside surface of
the jet. If a suitable wrench is not available, use a pipe
wrench or slip-joint plier on the recess of the jet as
shown in Figure 17. The conversion kit comes with a
different type jet. If the existing jet will be discarded,
it does not matter if the surfaces are damaged upon
removal.
Figure 17
7.3 Assemble H2O Components
7.3.1 Refer to Figure 18 and separate the water
jacket/jet assembly from the mixing chamber assembly
by using a 2.5 mm hex key to loosen the three setscrews
holding the jet to the mixing chamber. Then while twisting
the jet to loosen it, pull out to remove it from the chamber.
Nozzle
,
remove and save for reuse
Mixing Chamber, not needed
Jet
,
not needed
Material Hose,
remove and save
Gun
,
remove and save for reuse
*Hose Clamp, cut or
pry open to remove
* A new clam
p
is included with conversion kit.
If needed, apply wrench to recessed area.
Gun Assembly
Air Jet
Do not put a wrench on these surfaces.
Mixing Chamber
Water Hose
Water Jacket
Air-Induction Valve
Clamp,
Material Hose
Water Connection
(3/4" Garden hose swivel)
Water Valve

POWER GUN SUCTION BLAST TOOLS Page 11
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
Figure 18
NOTE: Review the assembly process and dry fit the
water jacket/jet assembly to the gun to determine its
final position before applying thread sealant.
7.3.2 While applying slight pressure on the trigger,
screw the water jacket into the gun until the trigger
begins to move. Make note of the position of the
water port (Shown in Figure 19) in relation to the
gun, then screw the jacket in all the way. Note the
position of the water port when the jacket is threaded
into the gun. If the port is facing down or slightly to either
side of the bottom position, it is okay. If it is sideways or
facing UP, loosen the jacket until the port is facing down
or slightly to either side. Do not loosen it beyond the
position noted above in bold Italics or the gun will leak
air. Make a note of this positioning; this will be the final
position of the jacket when it is reinstalled using thread
sealant.
7.3.3 Note which side the water valve handle is
facing. After the jacket is removed, the valve may be
rotated to the left or right side, whichever is most
comfortable for the operator.
7.3.4 Remove the water jacket/jet assembly from the
gun and if necessary rotate the water valve so the
handle is in the most comfortable side for the operator to
adjust.
7.3.5 Apply breakaway thread sealant such as Loctite
243 to the first few threads on the water jacket and
screw the jacket into the gun to the position noted in
Paragraph 7.3.2.
7.3.6 Set the gun assembly aside and refer to the
sealant’s directions to allow the sealant to cure. NOTE:
Do not attach any other components to the gun
assembly until the sealant has cured for the
recommended time.
Figure 19
* Apply breakaway sealant such as Loctite 243 to the male threads when assembling these parts.
**Apply Teflon thread sealant or other common thread sealant to the male threads on these parts.
Mixing Chamber
Water Jacket/Jet Assembly
Setscrews
*
**
Hose Clamp
Material Hose
Air Induction Valve
Mixin
g
Chamber, H2O
Nozzle
Water Jacket
Air Jet, H2O
Gun Assembly
Water Hose Assembly
Water Port
Water Valve
Water Hose
Fitting

POWER GUN SUCTION BLAST TOOLS Page 12
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
7.3.7 Slide the new material-hose clamp onto the
material hose and slip the material hose onto the mixing
chamber’s connection pipe. Crimp the clamp ears to
tighten the clamp.
7.3.8 Install nozzle: Make sure the mixing chamber
setscrews do not extend past the inside of the mixing
chamber. Fully insert the nozzle into the end of the
mixing chamber and tighten the setscrews to secure.
7.3.9 After the thread sealant has cured, apply Teflon
sealant tape or other common thread sealant to the male
threads on the water hose fitting and thread the fitting
into the water valve. Tighten to secure.
7.3.10 Make sure the mixing chamber setscrews do not
extend past the inside of the mixing chamber. Fully
insert the jet into the end of the mixing chamber.
7.3.11 Rotate the mixing chamber to obtain the most
comfortable position while holding the gun assembly and
material hose and then tighten the setscrews to maintain
the position.
7.3.12 The conversion is complete. Refer to the
instructions within the manual for operation.
8.0 TROUBLESHOOTING
WARNING
Failure to observe the following procedure before
performing any maintenance or service can
cause serious injury from the sudden release of
trapped compressed air.
Lockout and tagout the compressed air
supply.
Bleed the air supply line.
8.1 No Abrasive Flow
8.1.1 Foreign material in the mixing chamber
assembly: Remove nozzle and check for blockage in the
mixing chamber and nozzle.
8.1.2 Abrasive blockage in the material hose: If the
material hose packs with abrasive, it is a sign that the
abrasive mixture is too rich. Make sure the air-intake
holes in the lance are open. When using the lance into
bagged abrasive make sure the intake holes are not
buried in abrasive
8.1.3 Worn nozzle: Replace the nozzle when the
orifice is worn to 9/16” or sooner if production decreases
noticeably.
8.1.4 Air jet worn: Inspect end of air jet and replace
when wear reaches the orifice.
8.1.5 Air jet and/or nozzle not seated correctly: The jet
and nozzle must be fully seated into the mixing chamber,
and the setscrews must be tight.
8.1.6 Abrasive bridging at the lance’s abrasive inlet
holes: Frequent bridges or blockages are most likely
caused by damp abrasive. Refer to Section 8.3.
8.1.7 Hole worn in material hose: Inspect hose for
holes and inspect the clamps for leaks. Repair as
needed.
8.2 Plugged Nozzle
8.2.1 Foreign material in the nozzle: Clean and re-
install.
8.2.2 Abrasive mixture too rich: Make sure the air-
intake holes in the lance are open.
8.3 Abrasive Bridging
8.3.1 Frequent bridging or blockage at the lance can
be caused by damp abrasive. Some abrasives tend to
absorb moisture from the air, especially fine-mesh
abrasives in high-humidity areas. Empty the material
hose and hopper of abrasive, and store the abrasive in
an airtight container when not in use.
8.4 Neither Air Nor Abrasive Comes Out the
Nozzle When Trigger is Pulled
8.4.1 Inspect nozzle for blockage: Refer to Section 8.2.
8.4.2 Make sure that the air compressor is on and air
supply valves are open.
8.5 Air Leaks from Gun After Trigger is Released
8.5.1 Binding at the trigger, rod, or rod guide: Clean
abrasive from parts and inspect for cause of resistance.
8.5.2 Worn or damaged rod tip or obstruction between
the rod tip and air jet: Repair as needed.

POWER GUN SUCTION BLAST TOOLS Page 13
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
8.6 Abrasive Surge
8.6.1 Abrasive flow is too rich: Make sure the air-
intake holes in the lance are open.
8.7 Poor Suction in Material Hose
8.7.1 Inadequate air supply: Refer to the table in
Figure 4.
8.7.2 Blockage in material hose or nozzle: Refer to
Sections 8.1 and 8.2.
8.7.3 H2O Model: Make sure the air-induction valve is
closed.
8.7.4 H2O Model: Check for water in material hose.
Open water supply after pulling trigger; close water
supply before releasing trigger.
8.8 Blow-Back Through Material Hose
8.8.1 Blockage in nozzle: Remove the nozzle and
check for blockage.
8.9 Air Leak at Gun and Trigger Assembly
8.9.1 Faulty rod seal: Replace seal.
9.0 ACCESSORIES AND REPLACEMENT PARTS
9.1 Optional Accessories
Lock pin, coupling, package of 25 ......................... 11203
Safety cable, 1/2" to 1-1/4" OD hose .....................15012
Conversion kit, dry blast to wetblast, items in Fig. 20
with 16-ft. water hose ...................................... 29255
with 30-ft. water hose ...................................... 29339
Figure 20
9.2 Power Gun Systems
Description Stock No.
Power Gun with 3 cuft cart and hopper
with 16-ft. air and material hose ......................99860
with 30-ft. air and material hose ......................24687
Power Gun without cart and hopper
with 16-ft. air and material hose ......................90253
with 30-ft. air and material hose ...................... 24688
H2O Power Gun with 3 cuft cart and hopper
with 16-ft. air and material hose ......................29335
with 30-ft. air and material hose ......................29337
H2O Power Gun without cart and hopper
with 16-ft. air and material hose ......................29249
with 30-ft. air and material hose ...................... 29336
9.3 Blast Gun Assembly, Dry Blast ‒Figure 21
Item Description Stock No.
(-) Blast gun assembly
includes all items shown in Figure 21 .100477
1. Gun and trigger assembly ........................ 27532
2. Nozzle, 1/2" orifice w/tungsten liner ......... 90209
3. Air jet, 1/4" orifice, tungsten carbide.......... 90213
4. Mixing chamber ........................................ 90366
Figure 21
1
4
3
2
Mixing Chamber
Water Hose
Water Jacket
Air-Induction Valve
Clamp,
Material Hose
Water Connection
(3/4" Garden hose swivel)
Water Valve

POWER GUN SUCTION BLAST TOOLS Page 14
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
9.4 System Replacement Parts ‒Figure 22
Refer to Section 9.5, Figure 23 for additional
items used with the H2O Model.
Item Description Stock No.
1. Blast gun assembly, dry blast model
refer to Figure 21 for individual parts ....100477
2. Lance .........................................................90214
3. Hose, material, bulk specify feet required
16-ft. and 30-ft. are standard lengths .....24778
4. Hose, air, bulk, specify feet required
16-ft. and 30-ft. are standard lengths .....24779
5. Clamp, material hose ................................24780
6.* Clamp, 3/4” OD band ................................28018
7. Coupling, air hose .....................................00595
8. Lock pin, package of 25 ........................... 11203
9. Hopper and lid, 3 cuft ............................... 25589
10. Cart assembly .......................................... 25591
11. Hopper and cart assembly, 3 cuft ............ 99899
12. Hose assembly, coupled air, includes:
three of Item 6 (one loose) and one Item 7
16-ft. long, standard length ................ 28177
30ft. long ............................................ 28178
* Field installation of this clamp requires a BAND-IT®
tool, number C00169 or equal.
Figure 22
2 5
3
10
76*
1
5
6*
9
11
4
8
12

POWER GUN SUCTION BLAST TOOLS Page 15
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
9.5 Blast Gun Assembly, H2O Model ‒Figure 23
Item Description Stock No.
1. Gun and trigger assembly ........................ 27532
2. Nozzle, 1/2" orifice w/tungsten liner ......... 90209
3. Water injector jacket ............................... 100496
4. Gasket, NW-0, jet disc .............................. 29251
5. Waterjet disc ........................................... 100495
6. Air jet, H2O 1/4" orifice, tungsten carbide. 100490
7. Mixing chamber, H2O ............................. 100491
8. Nipple, 1/8" x 1/4" reducing ...................... 29252
9. Valve, 1/4" NPT ball (shutoff) ................... 29254
10. Clamp, 1/2" ID hose .................................. 29658
11. Hose, 1/4" ID water, bulk, per foot
specify length required .........................04911
12. Hose fitting, 1/4 MNPT x 1/4" barb ...........02714
13. Bushing, 1/2" x 1/4" brass ........................ 02706
14. Adaptor, 1/2-FPT x 3/4" fem water swivel .. 02705
15. Washer, pack of 6 ..................................... 04370
16. Sleeve, air induction valve....................... 100492
17. Knob, tensioning .....................................100493
18. Screw, M4 x 5 socket head .................... 100494
19. Clamp, material hose ................................24780
20. Setscrew, M5 x 6mm, 6 required .............. 29253
21. Hose, material, bulk specify feet required
16-ft. and 30-ft. are standard lengths ....24778
Figure 23
3
1
4 5 6 20
7
20
2
8
9
12
10
11
10
13
14
15
16
19
17
18
21
12

POWER GUN SUCTION BLAST TOOLS Page 16
© 2018 CLEMCO INDUSTRIES CORP. www.clemcoindustries.com Manual No. 24189, Rev. C 06/18
9.6 Gun and Trigger Assembly ‒Figure 24
Item Description Stock No.
(-) Gun and trigger assembly
includes all items shown in Figure 24 ....27532
(-) Service kit, gun assembly,
includes items 1 thru 12 .........................90208
1. Knob, control .............................................90584
2. Bushing, knob stem ...................................90585
3. Nut, control knob retaining ........................90586
4. Stem, control knob ....................................90587
5. Screw, stem stop .......................................90588
6. Spring, control knob ..................................90589
7. Spring, return .............................................90590
8. Guide, rod ..................................................90591
9. Setscrew, rod guide ...................................90592
10. Plug, rod and seal .....................................90593
11. Rod and tip assembly ................................90594
12. Seal, rod ....................................................90595
13. Gun body and trigger assembly
.........................Not available as separate item
Figure 24
5
3
1
4
26
7
10
9
8
11 13 12