DeVilbiss SRI PRO series Technical Bulletin

Service Bulletin

SB-2-855-B

Replaces SB-2-855-A

Technical Bulletin

SRi Pro range of Gravity Spray Guns

for spot repairs and small areas

AUTOMOTIVE REFINISHING

Page 2 SB-2-855-B

Table of Contents

Topic Page

EC Declaration of Conformity ................................................ 3

Operational Description .................................................... 3

Construction Features ...................................................... 4

Materials of Construction ................................................... 4

Speciﬁcations & Technical Data .............................................. 4

Safety Precautions ......................................................... 5

Parts List ................................................................. 6

Exploded Parts View ....................................................... 7

Installation, Operation, Preventive Maintenance & Cleaning, Spray Gun Lubrication .. 8

Parts Replacement/Maintenance ............................................. 9-13

A. Servicing Air Valve ................................................. 9

B. Replacing Air Valve ................................................. 10

C. Needle Packing, Spreader Valve Assembly .............................. 11

D. Replacing Separator Seal ............................................ 12

E. Chart 1 – Air Caps, Chart 2 – Fluid Nozzles & Fluid Needles ................ 13

Troubleshooting Possible Problems in Operation ............................... 14, 15

Accessories .............................................................. 16

Warranty ................................................................. 16

Page 3SB-2-855-B

EC Declaration of Conformity

We, Finishing Brands UK Ltd., Ringwood Rd, Bournemouth, Dorset, BH11 9LH, UK, as the manufacturer of the Spray gun model SRi-PRO, declare, under our sole responsibility, that the equipment to which this document relates is in conformity with the following standards or other normative documents:

BS EN 292-1 PARTS 1 & 2: 1991, BS EN 1953: 1999; and thereby conform to the protection

requirements of Council Directive 98/37/EEC relating to Machinery Safety Directive, and;

EN 13463-1:2001, council Directive 94/9/EC relating to Equipment and Protective Systems intended for use in Potentially Explosive Atmospheres protection level II 2 G X. This product also complies with the requirements of the EPA guidelines, PG6/34.

D. Smith, Vice President

1st May 2012

Operational Description

This SRi PRO Spray Gun is a professional quality gun designed with both high volume, low pressure (HVLP) technology or Trans-Tech® technology. HVLP Technology reduces overspray and limits air cap pressure to 0.7 bar (10 psi) (complies with rules issued by SCAQMD and other air quality authorities). Trans-Tech technology, when tested under recommended conditions with automotive reﬁnishing materials, has been found to exceed 65% transfer efﬁciency.

IMPORTANT: These Sprayguns are suitable for use with both waterbased and solvent based coating materials. These guns are not designed for use with highly corrosive and/or abrasive materials and if used with such materials it must be expected that the need for cleaning and/or replacement of parts will be increased. If there is any doubt regarding the suitability of a speciﬁc material, contact your DeVilbiss Distributor or DeVilbiss direct.

NOTE: This gun is not to be used with halogenated hydrocarbon solvents or cleaning agents such as 1,1,1,-Trichloroethane or methylene chloride. These solvents can react with the aluminium components used in this gun and cup. The reaction can become violent and lead to an equipment explosion.

Finishing Brands UK Ltd. reserve the right to modify equipment speciﬁcation without prior notice.

Page 4 SB-2-855-B

MATERIALS OF CONSTRUCTION

Gun Body Anodized aluminium Air Cap Nickel plated brass Fluid Nozzle, Fluid Needle, Fluid Inlet, Trigger Stud Stainless steel (303) Springs, Clips, Screws Stainless steel (303) Seals, Gaskets Solvent resistant Trigger Chrome plated steel Air Inlet, Body Bushing, Spreader Valve Body, Air Valve Nut,

Air Cap Retaining Ring, Knobs

Chrome plated brass

Air Valve Assembly Stainless steel (303), HPDE

SPECIFICATIONS & TECHNICAL DATA

Air Supply Connection Universal 1/4" BSP and 1/4" NPS male Maximum Static Air Inlet Pressure P1 = 175 psi (12 bar) Nominal Gun Air Inlet Pressure for HVLP (HS1) and

Trans-Tech

(TS1) with gun triggered

29 psi (2.0 bar)

Fluid Supply Connection 7/16 – 14 UNC Service Temperature 32 to 104°F (0 to 40°C) Gun Weight (gun only)

(with cup)

15.0 oz (425 g)

17.1 oz (485 g)

CONSTRUCTION FEATURES

Air Cap (nickel plated brass for long durability)

Air Cap Retaining Ring (allows easy rotation of air cap)

Fluid Nozzle (ideal for automotive topcoat systems)

Fluid Needle (grooved stem for easy removal)

Fluid Inlet (7/16” – 14 UNC thread) – accepts DeVilbiss SRI cup systems

Air Inlet (universal thread, accepts G 1/4 & 1/4 NPS)

Self Adjusting Needle Packing (for trouble free operation)

8 Trigger (ergonomic for comfort)

Trigger Stud & Screw (easy replacement design)

Fan Air Adjustment (stepless regulation for fan to round spray)

Fluid Adjustment (stepless regulation of ﬂuid volume)

Interchangeable Color ID System (4 colored rings supplied)

Anodized, forged aluminium gun body (ergonomic, good looking & durable, easy

to clean) 14 125cc Acetal Cup (easy clean, anti-static) 15 Cup Lid with Drip Free Vent (avoid drips)

Air Valve (design offers low pull force & low

pressure drop)

Gun acceptable for waterborne and solvent

borne applications

Gun can be used with DeVilbiss disposable

cups

Page 5SB-2-855-B

CAUTION

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

NOTE

Information that you should pay special attention to.

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.

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

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

Please read the following chart before using this equipment.

HAZARD CAUSE SAFEGUARDS

Fire

Solvent and coatings can be highly ﬂammable or combustible especially when sprayed.

Adequate exhaust must be provided to keep air free of accumulations of ﬂammable vapors.

Smoking must never be allowed in the spray area.

Fire extinguishing equipment must be present in the spray area.

Solvent Spray

During use and while cleaning and ﬂushing, solvents can be forcefully expelled from ﬂuid and air passages. Some solvents can cause eye injury.

Wear eye protection.

Inhaling Toxic Substances

Certain materials may be harmful if inhaled, or if there is contact with the skin.

Follow the requirements of the Material Safety Data Sheet supplied by your coating material manufacturer.

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

Use a mask or respirator whenever there is a chance of inhal

ing sprayed materials. The mask must be compatible with the material being sprayed and its concentration. Equipment must be as prescribed by an industrial hygienist or safety expert, and be NIOSH approved.

Explosion Hazard Incompatible Materials

Halogenated hydrocarbon solvents

- for example; methylene chloride and 1,1,1, Trichloroethane are not chemically compatible with the aluminum that might be used in many system components. The chemical reaction caused by these solvents reacting with aluminum can become violent and lead to an equipment explosion.

Guns with stainless steel internal passageways may be used with these solvents. However, aluminum is widely used in other spray application equipment - such as material pumps, regulators, valves, and this gun and cup. Check all equip

ment items before use and make sure they can also be used safely with these solvents. Read the label or data sheet for the material you intend to spray. If in doubt as to whether or not a coating or cleaning material is compatible, contact your material supplier.

General Safety

Improper operation or maintenance of equipment.

Operators should be given adequate training in the safe use and 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 Disorders ("CTD's")

CTD's, or musculoskeletal disorders, involve damage to the hands, wrists, elbows, shoulders, neck, and back. Carpal tunnel syndrome and tendonitis (such as tennis elbow or rotator cuff syndrome) are examples of CTD's.

Use of hand tools may cause cumulative trauma disorders ("CTD's").

CTD's, when using hand tools, tend to affect the upper extremities. Factors which may increase the risk of developing a CTD include:

1. High frequency of the activity.

2. Excessive force, such as gripping, pinching, or pressing with the hands and ﬁngers.

3. Extreme or awkward ﬁnger, wrist, or arm positions.

4. Excessive duration of the activity.

5. Tool vibration.

6. Repeated pressure on a body part.

7. Working in cold temperatures.

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

Pain, tingling, or numbness in the shoulder, forearm, wrist, hands, or ﬁngers, especially during the night, may be early symptoms of a CTD. Do not ignore them. Should you experience any such symptoms, see a physician immediately. Other early symptoms may include vague discomfort in the hand, loss of manual dexterity, and nonspeciﬁc pain in the arm. Ignoring early symptoms and continued repetitive use of the arm, wrist, and hand can lead to serious disability. Risk is reduced by avoiding or lessening factors 1-7.

Page 6 SB-2-855-B

PARTS LIST

REF. NO.

DESCRIPTION PART NO. QTY.

1 Air Cap Retaining Ring 1 2 Slip Ring 1 3 Air Cap 1 5 Retaining Ring Seal SRI-35-K5 1 6 Air Cap & Ring See chart 1, p13 1 8 Fluid Nozzle See chart 2, p13 1 9 Separator SRIPRO-2-K5 1 12* Body Bushing Seal 1 13 Body Bushing 1 14 Body Bushing & Seal 702728 1 15 Fluid Needle See chart 2, p13 1 16* Needle Spring 1 17* Needle Spring Pad 1 18 Fluid Adjusting Knob 1

Fluid Adjusting Knob, Spring & Pad Kit

PRO-3-K 1

20* Retaining Clip 1 21 Spreader Valve Body 1 22* Spreader Valve Seal 2

Spreader Valve Adjusting Knob

24* Valve Pin 1 25 Spreader Valve Assembly SRIPRO-401-K 1 26* Needle Packing 1 27* Packing Spring 1 28 Packing Nut 1

Packing, Spring & Packing Nut Kit

702731 1

30 Air Valve Body 1 31 Air Valve Cage 1

REF. NO.

DESCRIPTION PART NO. QTY.

32 Air Valve Poppet 1 33 Air Valve Spring 1 34 Air Valve Spring Pad 1 35 Air Valve Seal SN-34-K5 1 36 Air Valve Assembly 702732 1

37*

Trigger Stud Screw (T20 Star)

38 Trigger 1 39* Trigger Stud 1 40 Trigger, Stud & Screw Kit SN-42-K 1 41 Air Inlet SN-40-K 1

Color ID Ring Kit (4 colors)

702735 1

43 Airﬂow Valve PRO-404-K 1 44 Circlip 1 45 Wrench (kit of 2) SRI-50-K2 1

Air Valve Service Tool (included in 702732)

47 Air Flow Valve Knob 1

SERVICE PARTS

Spray Gun Repair Kit

(includes items marked *)

702736

Seal & Pin Kit, kit of 5

(items 20, 22 and 24)

GTI-428-K5

For accessories, see page 16

Page 7SB-2-855-B

Fluid Nozzle

(Torque to 80-90 in-lbs)

Fig. B

Fig. A

Views showing correct Air Cap/Retaining Ring assembly.

Page 8 SB-2-855-B

INSTALLATION

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

HS1, HVLP setup do not exceed 29.0 psi (2 bar) inlet pressure. This will insure HVLP compliance by limiting air cap pressure to 10 psi (0.7 bar).

1. Connect the gun to a clean, moisture and oil free air supply using a conductive hose.

NOTE

Install an air gauge at the gun handle. When gun is triggered on, adjust regulated pressure to 29.0 psi (2.0 bar). 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 an air adjusting valve is used at the gun inlet, use DeVilbiss model HAV-

512. Some competitive adjusting valves have signiﬁcant pressure drop that can adversely affect spray performance. The DeVilbiss model HAV-512 has minimal pressure drop, which is important for HVLP spraying.

2. Attach the gravity feed cup to the material inlet.

NOTE

Before using the gun, ﬂush it with solvent to ensure that the ﬂuid passages are clean.

OPERATION

1. Mix coating material to manufacturer’s instructions.

2. Strain the material.

3. Fill the cup to no more than 1/2 inch from the top of the cup. DO NOT OVERFILL.

4. Attach Cup Lid. Make sure that the cup lid vent hole is clear.

5. Turn ﬂuid adjusting knob (18) clockwise to prevent ﬂuid needle movement.

6. Turn spreader valve adjusting knob (23) counter clockwise to fully open.

7. Adjust inlet air pressure to 29.0 psi (2.0 bar).

8. Turn ﬂuid adjusting knob counter clockwise until ﬁrst thread shows.

9. Test spray. If the ﬁnish is too dry, reduce airﬂow by reducing air inlet pressure.

10. If ﬁnish is too wet, reduce ﬂuid

ﬂow by turning ﬂuid adjusting knob (18) clockwise. If atomization is too coarse, increase inlet air pressure. If too ﬁne, reduce inlet pressure.

11. The pattern size can be reduced

by turning spreader valve knob (23) clockwise.

12. Hold gun perpendicular to surface

being sprayed. Arcing or tilting may result in uneven coating.

13. The recommended spray distance

is 3-6 in (75-150 mm).

14. Spray edges ﬁrst. Overlap each

stroke a minimum of 75%. Move gun at a constant speed.

15. Always turn off air supply and

relieve pressure when gun is not in use.

PREVENTIVE MAINTENANCE & CLEANING

To clean air cap and ﬂuid nozzle, brush exterior with a stiff bristle brush. If necessary to clean cap holes, use a broom straw or toothpick if possible. If a wire or hard instrument is used, extreme care must be used to prevent scratching or burring of the holes which will cause a distorted spray pattern.

To clean ﬂuid passages, remove excess material from cup, then ﬂush with gun wash solution. Wipe the gun exterior with a dampened cloth. Never completely immerse in any solvent or cleaning solutions as this is detrimental to the lubricants and life of the spray gun.

NOTE

When replacing the ﬂuid nozzle or ﬂuid needle, replace both at the same time. Using worn parts can cause ﬂuid leakage. See page 13, Chart 2. Also, replace the needle packing at this time. Torque the ﬂuid nozzle to 80-90 in-lbs (9-10 Nm). Do not over tighten.

CAUTION

To prevent damage to ﬂuid nozzle (8) or ﬂuid needle (15), be sure to either 1) pull the trigger and hold while tightening or loosening the ﬂuid nozzle, or 2) remove ﬂuid adjusting knob (18) to relieve spring pressure against needle collar.

SPRAY GUN LUBRICATION

Daily, apply a drop of SSL-10 spray gun lube at trigger bearing stud (39) and the stem of the air valve (32). The shank of the ﬂuid needle (15) where it enters the packing nut (28) should also be oiled. Make sure the retaining ring (1) threads are clean and free of foreign matter. Before assembling retaining ring to spray gun, clean the threads thoroughly, then add two drops of SSL-10 spray gun lube to threads. The ﬂuid needle spring (16) should be coated with a very light grease. For best results, lubricate the points indicated, daily.

A. Trigger Points B. Packing C. Adjusting Valves D. Gun/Air Cap Threads E. Air Valve Cartridge

Page 9SB-2-855-B

PARTS REPLACEMENT/MAINTENANCE

AIR VALVE INSTRUCTIONS

Servicing Air Valve

Reasons to service air valve:

A) Air valve not functioning correctly (may need

cleaning).

B) Routine maintenance.

C) Air leaks (advise replacement, see p10)

1. Remove trigger using a Star T20 key. (See ﬁg 1 & 2)

2. Unscrew air valve using a (14 mm wrench. (See fig 3)

3. Remove air valve by gripping stem. (See ﬁg 4)

4. Remove spring with spring pad. (See ﬁg 5)

5. DO NOT REMOVE REAR SEAL (35) FROM GUN

BODY. (See ﬁg 6)

6. DO NOT REMOVE PLASTIC CAGE FROM AIR VALVE

BODY AS THIS MAY DAMAGE THE CAGE. (See ﬁg 7)

7. CLEAN

a. Remove all paint build up. (See ﬁg 8) b. The 4 poppet holes must be clear. (See ﬁg 9) c. Stem must be free to ﬂoat in poppet. (See ﬁg 10) d. Stem must slide through cage bore with slight

resistance (due to seal).

e. Rear seal must look clean and in position in the

bore. (See ﬁg 6)

f. If any of the above cannot be rectiﬁed, replace the

air valve. (See Replacing Air Valve, p10)

8. Replace spring ensuring the end with the plastic

bearing pad goes in ﬁrst. (See ﬁg 5)

9. Insert air valve assembly into gun and carefully feed

over the spring and through the rear seal. (See ﬁg 11)

10. Tighten air valve assembly using ﬁngers ﬁrst, and

then tighten with a 14mm wrench. (See ﬁg 12)

11. Replace trigger. (See ﬁgs 2 & 1)

12. If there is an air leak through the gun, the air valve

may need replacing. (See Replacing Air Valve)

Page 10 SB-2-855-B

PARTS REPLACEMENT/MAINTENANCE

AIR VALVE INSTRUCTIONS

Replacing Air Valve

Reasons to replace air valve:

A) Air leak through the gun.

B) Air valve not operating correctly.

1. Remove trigger using a Star (T20) key. (See ﬁgs 13 & 14)

2. Unscrew air valve using a 14 mm wrench. (See ﬁg 15)

3. Remove air valve by gripping the stem. (See ﬁg 16)

4. Remove spring with spring pad. (See ﬁg 17)

5. Hook out rear seal using Service Tool (46). (See ﬁgs 18 & 19)

6. Clean air valve bores in gun body with a brush.

7. Place new rear seal onto Service tool (46); grooves must ﬁt in service tool form. (See ﬁg 20)

8. Push rear seal ﬁrmly into hole up to shoulder, using Service tool. (See ﬁgs 21 & 22)

9. Insert new spring, ensuring the end with the plastic bearing pad goes in ﬁrst. (See ﬁg 17)

10. Insert air valve assembly into gun and carefully feed

over the spring and through the rear seal. (See ﬁg

23)

11. Tighten air valve assembly using ﬁngers ﬁrst, then

tighten with a 14 mm wrench. (See ﬁg 24)

12. Replace trigger. (See ﬁgs 14 & 13)

Page 11SB-2-855-B

PARTS REPLACEMENT/MAINTENANCE

NEEDLE PACKING INSTRUCTIONS

Replacing Needle Packing

13. Remove trigger using a Star (T20) key. (See ﬁgs 25 & 26)

14. Remove ﬂuid adjusting knob and needle spring with spring pad from gun. (See ﬁgs 27 & 28)

15. Remove ﬂuid needle from gun body. (See ﬁg 29)

16. Loosen and remove packing nut using a straight blade screwdriver. (See ﬁgs 30 & 31)

17. Discard old packing and packing spring if replacing. Clean packing if reusing. Also clean packing spring and nut. (See ﬁg 32)

18. Re-assemble the packing, (See ﬁg 32). Assemble into gunbody by hand (see ﬁg 33) and then tighten. (See ﬁgs 30 and 31)

19. Insert ﬂuid needle all the way into gun body seating in ﬂuid nozzle. (See ﬁg 34)

20. Insert needle spring, spring pad, and ﬂuid adjusting knob. (See ﬁgs 28 & 27). Reinstall trigger. (See ﬁgs 25 & 26)

21. Trigger gun fully and screw in ﬂuid adjusting knob until it stops. Back it off 1/2 turn and gun will have full needle travel.

22. Trigger gun several times to verify correct operation.

SPREADER VALVE ASSEMBLY REPLACEMENT/MAINTENANCE

The spreader valve assembly can be replaced if damaged. Remove using a 14 mm wrench (See figs 35 & 36). The internal seal can be replaced and is included in the PRO Gun Rebuild Kit.

Page 12 SB-2-855-B

PARTS REPLACEMENT/MAINTENANCE

SEPARATOR SEAL INSTRUCTIONS

Replacing Separator Seal

1. Remove air cap and retaining ring. (See ﬁg 37)

2. Remove ﬂuid adjusting knob, spring, and spring pad. (See ﬁgs 38 & 39)

3. Remove ﬂuid needle from gun body. (See ﬁg 40)

4. Remove ﬂuid nozzle using SRI-50 (6 mm) wrench. (See ﬁgs 41, & 42)

5. Remove Separator. (See ﬁg 43)

6. Clean front of gun if required, using a soft brush, as well as the ﬂuid nozzle, air cap, and retaining ring.

7. Place a new Separator Seal into the front of the gun, making sure the ﬂat side of the seal is aligned with the ﬂat in the gun. (See ﬁg 44).

8. Fit Fluid Nozzle, Air Cap, and Retaining Ring. Torque the Fluid Nozzle to 80-90 in-lbs (9-10 Nm). Don’t over torque the Fluid Nozzle. (See ﬁgs 45, 46, and 37)

9. Insert Fluid Needle all the way into the Gun Body, seating in the Fluid Nozzle. (See ﬁg 47)

10. Reassemble Needle Spring, Spring Pad, and Fluid

adjusting Knob. (See ﬁg 47)

11. Trigger gun fully and screw in Fluid Adjusting Knob

until it stops. Back it off 1/2 turn and gun will have full needle travel. (See ﬁg 48)

12. Trigger gun several times to verify correct operation.

(See ﬁg 48)

1/2

turn

80-90 in-lbs

(9-10 Nm)

Page 13SB-2-855-B

PARTS REPLACEMENT/MAINTENANCE

CHART 1 – AIR CAPS

AIR CAP & RING

TECHNOLOGY

MARKING

AIR CAP

RECOMMENDED

INLET

PRESSURE

AIR FLOW

COMPUTER NO. PART NO. (L/min) (CFM)

803296 SRIPRO-101-HS1 HVLP HS1 29.0 psi (2.0 bar) 135 4.8 803297 SRIPRO-100-TS1 TRANS-TECH

TS1 29.0 psi (2.0 bar) 100 3.5

NOTE: When removing air cap from retaining ring, don’t remove the Slip Ring (2) or Retaining Ring Seal (5) from the Retaining Ring. Damage to the parts may occur. Slip ring and Retaining Ring seal are not available as replacements. Simply wipe parts clean and reassemble with new or clean air cap.

CHART 2 – FLUID NOZZLE RANGE & FLUID NEEDLE

FLUID NOZZLE FLUID NEEDLE

COMPUTER NO. PART NO. COMPUTER NO. PART NO.

803298* SRIPRO-200-08-K*

803302 SRIPRO-300-0810-K

803299* SRIPRO-200-10-K* 803300* SRIPRO-200-12-K* 803303 SRIPRO-300-1214-K

*Includes (1) SRIPRO-2 separator

NOTE: When replacing the ﬂuid nozzle or ﬂuid needle, replace both at the same time. Torque to 80-90 in-lbs (9-10 Nm). Don’t over tighten the ﬂuid nozzle. Use SRI-50 (6mm) wrench supplied with the gun and check with a torque wrench.

IMPORTANT NOTE: The SRI PRO and old SRI ﬂuid nozzles and aircaps ARE NOT INTERCHANGEABLE between the 2 models. Any attempt to ﬁt ﬂuid nozzles or caps onto the wrong Spray Gun may cause damage to the parts or the Spraygun body and invalidate the warranty.

Page 14 SB-2-855-B

TROUBLESHOOTING POSSIBLE PROBLEMS IN OPERATION

CONDITION CAUSE CORRECTION

Heavy top or bottom pattern

Horn holes plugged. Clean. Ream with non-metallic point.

Obstruction on top or bottom of ﬂuid nozzle.

Clean.

Cap and/or nozzle seat dirty. Clean.

Left or right side horn holes plugged. Clean. Ream with non-metallic point.

Heavy right or left side pattern

Dirt on left or right side of ﬂuid nozzle.

Clean.

Remedies for the top-heavy, bottom-heavy, right-heavy, and left-heavy patterns:

1. Determine if the obstruction is on the air cap or the ﬂuid nozzle. Do this by making a test spray pattern. Then, rotate the cap one-half turn and spray another pattern. If the defect is inverted, obstruction is on the air cap. Clean the air cap as previously instructed. Also check for dried paint just inside the cap center hole opening; remove by washing with solvent.

2. If the defect is not inverted, it is on the ﬂuid nozzle. Clean nozzle. If problem persists, renew nozzle.

Heavy centre pattern.

Spreader adjustment valve set too low.

Turn out counter clockwise to achieve correct pattern.

Atomizing pressure too low. Increase pressure.

Material too thick. Thin to correct consistency.

Split spray pattern

Air pressure too high. Reduce at regulator or gun handle.

Fluid adjusting knob turned in too far.

Turn out counter clockwise to achieve correct pattern.

Spreader adjusting valve set too high.

Turn in clockwise to achieve correct pattern.

Jerky or ﬂuttering spray

Loose or damaged ﬂuid nozzle/seat Tighten or replace

Loose or broken cup ﬂuid nipple Tighten or replace cup

Material level too low Reﬁll

Container tipped too far Hold more upright

Obstruction in ﬂuid passage Back ﬂush with solvent

Loose ﬂuid needle packing nut Tighten

Damaged ﬂuid needle packing Replace

Paint bubbles in cup

Fluid nozzle not tight.

Fluid nozzle not tight. Tighten to 9-10 Nm (80-90 in-lbs).

Page 15SB-2-855-B

Fluid leaking or dripping from cup lid

Cup lid loose. Push in or replace.

Dirty cup or lid. Clean.

Cracked cup or lid. Replace cup and lid.

Starved spray pattern

Inadequate material ﬂow

Wind ﬂuid adjusting knob out or change to larger ﬂuid nozzle size.

Blocked vent in Cup lid Clean lid and unblock vent.

Low atomization air pressure

Increase air pressure and rebalance gun.

Excessive overspray

Air pressure to high. Reduce air pressure.

Gun too far from work surface. Adjust to correct distance.

Dry spray

Air pressure too high. Reduce air pressure.

Gun too far from work surface. Adjust to correct distance.

Gun motion too fast. Slow down.

Fluid ﬂow too low.

Wind out needle adjusting screw or use larger nozzle size.

Fluid leaking from packing nut

Packing worn. Replace.

Fluid leaking or dripping from front of gun

Fluid nozzle or ﬂuid needle worn or damaged.

Replace ﬂuid nozzle and ﬂuid needle.

Foreign matter in ﬂuid nozzle. Clean.

Fluid needle dirty or stuck in needle packing

Clean.

Wrong size ﬂuid needle or ﬂuid nozzle.

Replace ﬂuid nozzle and ﬂuid needle.

Fluid dripping or leaking from bottom of cup

Cup loose on gun. Tighten.

Cup ﬂuid inlet seat dirty. Clean.

Runs and sags

Too much material ﬂow.

Turn ﬂuid adjusting knob clockwise or switch to smaller ﬂuid nozzle and ﬂuid needle size.

Material too thin. Mix correctly or apply light coats.

Gun tilted on an angle, or gun motion too slow.

Hold gun at right angle to work and adapt to correct gun technique.

TROUBLESHOOTING POSSIBLE PROBLEMS IN OPERATION (CONTINUED)

+ 33 hidden pages

DeVilbiss SRI PRO series Technical Bulletin

Specifications and Main Features

Frequently Asked Questions

User Manual