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Cleaning and Maintenance of Spray Gun

Cleaning and Maintenance of Spray Gun

Pour remaining paint out after use, clean each each section of the spray gun with thinner.

Spray defined amount of thinner to clean fluid passages until clean enough. 

Then clean with a soft cloth. If not, remaining paint in the fluid passages may damage the spray gun after solidification.


  • First release air and pressure fully according to item No.2 of “Improper use of equipment” of WARNING on page 1 to 2.

  • Tip of fluid needle set has a sharp point. Do not touch the tip of needle valve at the maintenance.

  • Be careful not to damage the tip of fluid nozzle.

  • Only an experienced person who is fully conversant with the equipment can do maintence and inspection.


  • Never use commercial or other parts instead of original spare parts.

  • Never immerse the whole gun into any solvent or cleaning solution such as thinner for over 1minute.

    If not, it may be detrimental to the lubricants, and the seals inside may be out of shape and lead to leakage, even there's no any rubber parts used inside the gun, such as o-ring.

  • When replacing the fluid nozzle or fluid needle, replace both at the same time. 

    Using worn parts can cause fluid leakage. Also, replace the needle packing at this time. 

    Torque the fluid nozzle to 18~20Nm (160~180lb.in). Do not over tighten.

  • To prevent damage to fluid nozzle or fluid needle, be sure to either pull the trigger and hold while tightening or loosening the fluid nozzle, or remove fluid adjusting knob to relieve spring pressure against needle collar.

  • The gravity cup is made from special anti-static materials, but it is still improtant to avoid generating static charges. 

    The cup must not be cleaned or rubbed with a dry cloth or paper. It is possible to generate a static charge by rubbing witch, if discharged to an earthed object could create an incendive spark and cause solvent vapours to ignite. 

    Only use a dampened cloth or antistatic wipes if manual cleaning is required within a hazardous area. 

  • For routine clean/maintenance, do not dismount any other part than air cap, nozzle and needle from the gun (The spray head may needs to be cleaned it it is dirty).

    If not, the seals & packagings inside may face a risk of being out of shape and lead to leakage.

Step-by-step procedure


1. Pour remaining paint out after use. Clean fluid passages and air cap set. Spray a small amount of thinner to clean fluid passages.

1. Incomplete cleaning can fail pattern shape and uniform particles. Especially clean fully and promptly two-component paint after use

2. Clean each section with brush soaked with thinner and wipe out with waste cloth.

2. Do not immerse the whole in thinner for over 1 minute. If done, it may damage parts inside, and lubricating may be needed.

3. Before disassembly, fully clean fluid passages.

(1) Disassemble fluid nozzle.

Usespanner to remove fluid nozzle.

(2) Disassemble fluid needle set.

You do not need to remove fluid/needle adj. guide set from gun body. Remove fluid adj. knob and fluid needle spring, and then pull out fluid needle spring, and then pull out fluid needle from back of housing.

3. During disassembly, do not scratch housing section.

(1)  Remove fluid nozzle after removing fluid needle or while keeping fluid needle pulled, in order to protect housing section.

(2)  Be careful when handing tip of fluid needle since it is sharp.

4. In order to assemble air valve, first assemble air valve & air valve spring & fluid adj. guide together.

Next, insert fluid needle set into fluid adj. guideset, then fit it to gun body set and screw fluid adj. guide set.

4. Service air valve only when it is not functioning correctly (may need cleaning) orsignificantly air leaks.

If you try to fit air valve spring and air valve to gun body without fluid needle set, air valve will not be fitted correctly and lop packing inside fluid adj. guide will be damaged.

5. When you want to adjust fluid needle packing set, first tighten it by hand while fluid needle set remains inserted.

Then tighten it further carefully by spanner.

5. Serviceneedle packing only when it is not functioning correctly or significantly air leaks.

Too much tightening of fluid needle packing nut can cause bad movement of fluid needle set and fluid leakage from the tip of fluid needle.

When you tighten it too much, first fully loosen it and then tighten it again carefully.

6. Turn pattern adj. knob or air adj. knob counterclockwise to fully open, and then tighten pattern adj. set or air adj. set.

6. If pattern adj. knob or air adj. knob is not fully opened, tip of it can contact and damage fluid nozzle and cause seizure of thread.

Where to inspect

Parts replacement

1. Each hole passage of air cap and fluid nozzle.

Replace if it is crushed or deformed.

2. Packing and seals

Replace if it is deformed or worn out.

3. Serious leakage between fluid nozzle and needle.

Replace them both if leakage does not stop after fully cleaning fluid nozzle and fluid needle.

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