De Havilland JGA-510, HLPV Service Manual

SERVICE MANUAL

JGA-510 (HVLP)

SUCTION/PRESSURE FEED

SPRAY GUN

EN

(GOVERNMENT NSN NO. 4940-01-046-9919 = KK-4987-2)

MAJOR REPAIR KIT KK-4987-2

MINOR REPAIR KIT KK-5034

IMPORTANT: Before using this equipment,
read all safety precautions and instructions.
Keep for future use.

DESCRIPTION

The high volume low pressure JGA-HVLP gun
is designed to apply a wide variety of finish­ing materials. This gun was manufactured
to provide maximum transfer efficiency by

limiting air cap pressure to 10 psi (complies
with rules issued by SCAQMD and other air
quality authorities). The gun is available in

both suction feed and pressure feed versions
of fluid delivery.

This gun will produce approximately
10 psi cap pressure at 50 psi gun inlet
pressure, as measured at the gun inlet.
An air cap test kit (see Accessories, Page

6) should be used to insure 10 psi air cap
pressure is not exceeded.

Note

This gun includes 300 series
stainless steel fluid passages
and 400 series tip and needle.
Guns may be used with chlorinated
solvent materials. See Page 2 for
additional warnings.

IMPORTANT: This gun may be used with
most common coating and finishing ma­terials. It is designed for use with mildly
corrosive and nonabrasive materials. If
used with other high corrosive or abra­sive materials, it must be expected that
frequent and thorough cleaning will be
required and the necessity for replacement
of parts will be increased.

INSTALLATION

For maximum transfer efficiency, do not use
more pressure than is necessary to atomize
the material being applied.

Connect the gun to a clean, moisture and oil
free air supply using a hose size of at least
5/16" I.D. Do not use 1/4" I.D. hose (25' x 1/4"
hose at 18 CFM has a pressure loss of 25 psi.
25' x 5/16" hose at 18 CFM has a pressure
loss of 8 psi.

Note

Depending on hose length, larger
I.D. hose may be required. Install a
HAV-501 air gauge at the gun handle
and air cap test kit over tip. When
gun is triggered on, adjust regulated
pressure to desired setting to pro­vide a maximum of 10 psi at the air
cap. Do not use more pressure than

is necessary to atomize the mate­rial being applied. Excess pressure

will create additional overspray and
reduce transfer efficiency.

Note

If quick connects are required,
use only high flow quick con­nects approved for HVLP use
such as DeVilbiss HC-4419 &
HC-4699. Other types will not flow
enough air for proper gun operation.

Note

If an air adjusting valve is used
at the gun inlet, use DeVilbiss Model
HAV-500 or HAV-501. Some compet­itive adjusting valves have signifi­cant pressure drop that can adverse­ly affect spray performance. Models
HAV-500 and 501 have minimal
pressure drop, which is important
for HVLP spraying.

OPERATION

Strain material thru 60 or 90 mesh screen.
Best atomization will occur with 10 psig
air cap pressure. However, some materials
can be sprayed at lower pressures, improving
transfer efficiency.

Open fluid adjusting screw (27) by turning
counterclockwise. If gun is a suction feed
version, make sure vent hole in suction
cup is clean. If gun is a pressure feed
version, turn on air to paint supply
and adjust fluid pressure to deliver the
desired paint volume.

Turn on air supply to gun and set gun
inlet pressure to lowest recommended
pressure for material being sprayed. Spray
a test area. Air pressure and paint flow
should be adjusted to provide a uniform
dispersion of atomized paint throughout
the pattern. Keep air pressure as low as
possible to minimize bounce-back and
overspray. Excessive fluid flow will result
in heavy center spray patterns. Inade­quate flows may cause the pattern to split. See
TROUBLESHOOTING, page 5, if any problems
occur. If finer atomization is required, increase
gun inlet pressure. If a reduced fluid flow rate
is required, turn fluid adjusting screw (27)
clockwise until desired fluid flow is obtained
or reduce fluid pressure (pressure feed only).

Order a free copy of Spray Gun Troubleshoot­ing and Preventive Maintenance Guide, SB­2-001 latest revision, for details concerning
setup of spray guns.

PREVENTIVE MAINTENANCE

To clean air cap and fluid tip, brush exterior
with a stiff bristle brush. If necessary
to clean cap holes, use a broom straw
or toothpick. Never use a wire or hard
instrument. This may scratch or burr
holes causing a distorted spray pattern. See
page 6 for gun cleaning accessories.

To clean fluid passages, remove excess
material at source Then proceed as follows:

Suction Feed Guns - Wash out cup with
solvent. Wipe off cup suction tube, then
fill cup with solvent. Spray until fluid
passages are clean.

Pressure Feed Guns - Flush fluid delivery sys­tem with a suitable solvent using a device such
as the SolventSaver™ (see ACCESSORIES).

Wipe exterior with a solvent dampened cloth,
or use 29-3100 Scrubs
Never completely immerse in solvent as this
is detrimental to the performance and gun
life expectancy, as well as destroying the
lubricants and packings.

When replacing the fluid tip or fluid
needle, replace both at the same
time. Using worn parts can cause
fluid leakage. See Chart 1 for order­ing information. Also, replace the
needle packing at this time. Lightly
lubricate the threads of the fluid tip
before reassembling. Torque to
20-25 ft. lbs.

To prevent damage to fluid tip
(3) or fluid needle (32), be sure
to either 1) pull the trigger and
hold while tightening or loos­ening the fluid tip, or 2) re­move fluid needle adjusting screw
(27) to relieve spring pressure
against needle collar.

®

(shown on page 6.)

Note

SB-2-248-L (11/2014) 1 / 8

EN

SAFETY PRECAUTIONS

This manual contains information that is important for you to know and understand. This information relates to USER SAFETY
and PREVENTING EQUIPMENT PROBLEMS. To help you recognize this information, we use the following symbols.
Please pay particular attention to these sections.

Note

Important safety information - A hazard
that may cause serious injury or loss of life.

HAZARD CAUSES SAFEGUARDS

Fire

Solvent and coatings can be highly flammable Adequate exhaust must be provided to keep air free of

or combustible especially when sprayed. accumulations of flammable vapors.

Smoking must never be allowed in the spray area.

Fire extinguishing equipment must be present in spray area.

Solvent Spray

solvents can be forcefully expelled from fluid
and air passages. Some solvents can cause
eye injury.

Inhaling Toxic
Substances

Adequate exhaust must be provided to keep the air free of toxic
materials.

Use a mask or respirator whenever there is a chance of inhaling
sprayed materials. The mask must be compatible with the
material being sprayed and its concentration. Equipment must
be as prescribed by an industrial hygienist and be NIOSH
approved.

Explosion Hazard
Incompatible
Materials

that might be used in many system components. regulators, valves and cups. Check all equipment items before
The chemical reaction caused by these solvents use and make sure they can also be used safely with these
reacting with aluminum can become violent and solvents. Read the label or data sheet for the material you
lead to an equipment explosion. intend to spray. If in doubt as to whether or not a coating or
cleaning material is compatible, contact your material supplier.

General Safety

maintenance of the equipment (in accordance with the
requirements of NFPA-33, Chapter 15). Users must comply with
all local and national codes of practice and insurance company
requirements governing ventilation, fire precautions, operation,
maintenance and housekeeping. These are OSHA Sections

1910.94 and 1910.107 and NFPA-33.

Cumulative Trauma Use of hand tools may cause cumulative trauma Pain, tingling, or numbness in the shoulder, forearm, wrist,

Disorders (CTD's)

symptoms of a CTD. Do not ignore them. Should you
CTD's, or musculo- CTD’s, when using hand tools, tend to affect the experience any such symptoms, see a physician immediately.
skeletal disorders, upper extremities. Factors which may increase Other early symptoms may include vague discomfort in the
involve damage to the risk of developing a CTD include: hand, involve loss of manual dexterity, and nonspecific pain
the hands, wrists 1. High freequency of the activity. in the arm. Ignoring early symptoms and continued repetitive
elbows, shoulders, 2. Excessive force, such as gripping, pinching use of the arm, wrist and hand can lead to serious disability.
neck and back. or pressing with the hands and fingers.
Carpal tunnel 3. Extreme or awkard finger, wrist, or arm
syndrome and positions.
tendinitis (such 4. Excessive duration of the activity.
as tennis elbow or 5. Tool vibration.
rotor cuff syndrome) 6. Repeated pressure on a body part.
are examples of 7. Working in cold temperatures.

CTD's.

CTD's can also be caused by such activities as sewing, golf, tennis and bowling, to name a few.

During use and while cleaning and flushing, Wear eye protection.

Certain materials may be harmful if inhaled, Follow the requirements of the Material Safety Data Sheet

or if there is contact with the skin. supplied by your coating material manufacturer.

- Halogenated hydrocarbon solvents - for example; Guns with stainless steel internal passageways may be used

methylene chloride and 1, 1, 1 - Trichloroethane with these solvents. However, aluminum is widely used in

are not chemically compatible with the aluminum other spray application equipment - such as material pumps,

Improper operation or maintenance of equipment. Operators should be given adequate training in the safe use &

disorders (“CTD’s”). hands or fingers, especially during the night, may be early

Important information that tells how to
prevent damage to equipment, or how to
avoid a situation that may cause minor injury.

The following hazards may occur during the normal use of this equipment.

Please read the following chart before using this equipment.

CA PROP

65

Information that you should pay special
attention to.

PROP 65 WARNING

WARNING: This product contains chemicals
known to the State of California to cause
cancer and birth defects or other
reproductive harm.

SB-2-248-L (11/2014)2 / 8

EN

SPRAY GUN LUBRICATION

Daily, apply a drop of •SSL-10 spray gun
lube at trigger bearing stud (20) and the
stem of the air valve (12) where it enters
the air valve assembly (16). The shank of
the fluid needle (32) where it enters the
packing nut (18) should also be oiled.
The fluid needle packing (17) should be
lubricated periodically. Make sure the
baffle (5) and retaining ring (1) threads are
clean and free of foreign matter. Before
assembling retaining ring to baffle, clean
the threads thoroughly, then add two
drops of SSL-10 spray gun lube to
threads. The fluid needle spring (29) and
air valve spring (11) should be coated
with a very light grease, making sure that
any excess grease will not clog the air pas­sages. For best results, lubricate the points
indicated, daily.

•A Material Safety Data Sheet is available
from DeVilbiss upon request.

A. Trigger Points

A

B. Packing
C. Adjusting
Valves

C
D. Baffle
Threads
E. Air Valve
Cartridge

D

B

E

PARTS REPLACEMENT - FLUID INLET
GASKET (6) REPLACEMENT INSTRUC­TIONS

1. Remove fluid inlet adapter (8) with ap-

propriate wrench.

2. Clean Loctite from gun body inlet threads

and seal area.

3. Place gasket (6) squarely onto the fluid

inlet adapter and push it down until it
is flat against the shoulder.

4. Place a couple of drops of medium

strength thread sealant (i.e. Loctite 242
blue, or equal) on threads before install­ing fluid inlet adapter.

5. Torque fluid inlet adapter to 20-25 ft. lbs.

and tighten locknut.

Figure 1 Baffle

Maximum air pressure required
to assure compliance of 10 psi
Max. Cap Pressure - this reading
must be taken at the spray gun
handle inlet fitting.

50

57

Chart 1

FLUID TIP AND NEEDLE

Tip Size
Needle Tip (I.D.)
In. mm

JGA-402-DEX AV-2125-D .086 2.2

JGA-402-E AV-2125-DE .070 1.8
JGA-402-FX AV-2125-DFX .042 1.1

Note: Do not use AV-1 copper
gasket with this spray gun.

Chart 2

AIR CAP & BAFFLE COMBINATION

No. Stamped on Part

Air Cap Ref. No. 2 Ref. No. 5
Part No. Baffle Air Cap Baffle

57 57 JGHV-101-57 JGHV-457-57

Set

JGHV-101-57 Air Cap
Performance Charts

Graph 1

Air Flow Rate (SCFM)

Gun Inlet Pressure (PSI)

Graph 2

Air Cap Pressure (PSI)

Gun Inlet Pressure (PSI)

DISASSEMBLY INSTRUCTIONS ­NEW BAFFLE ASSEMBLY

The baffle design incorporates a tight,
press fit with the fluid tip, assuring a
positive air seal. With this design, the
baffle may pull away from the gun body
when the tip is removed and stay locked
onto the fluid tip. If this occurs, follow the
instructions below.

Note

A bench vise should be used for
convenience and to avoid damage
to the spray gun.

1. Secure the spray gun in a bench vise
with padded jaws, or use a rag to
avoid scratching the gun body.

2. Using a 1/2" socket, loosen the fluid
tip three (3) turns only, which will
leave about a 1/16" gap between the
baffle gasket and gun body. See

Figure 2. Do not loosen the fluid tip
more than three (3) turns, as

damage may occur.

Figure 2

Loosen fluid tip

Fluid Tip

3 turns only.

Baffle

Baffle
Gasket

1/16" gap
(approx.)

Bench
Vise

3. Place a 1" socket (12 pt.) over the fluid
tip so that it rests on the top surface
of the baffle. See Figure 3.

4. Press downward on the socket with
sufficient force to free the baffle from
the tip. See Figure 3.

5. The fluid tip and baffle can now be
removed normally from the gun.

Figure 3

Press Down

1" Socket
(12 pt.)

Air cap number located on face
of cap - cap number must cor­respond with baffle number to
assure 10 psi cap pressure.

SB-2-248-L (11/2014) 3 / 8