Troubleshooting And Fault Rectification; Replacement Of The Spray Gun Components; Replacement Of The Needle; Replacement Of Needle Seal Packing - WALTHER PILOT PILOT III F Instrucciones De Servicio

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Troubleshooting and fault rectification

Warning
Prior to any seervicing and repair work: Make sure that the spray gun is in unpres-
surized condition, i.e. air input must be shut off - if not, imminent risk of injury.
Fault Cause
Material needle or nozzle
soiled or damaged
Gun is dripping
The setting screw (N° 14) tur-
ned too far to the back
Not enough material in materi-
al tank
Cup is tilted too much during
spraying operation
Pulsating or unsteady jet
Material nozzle loose or dama-
ged
Material is overweight for ope-
ration with syphon-feed cup
Gun keeps blowing in Valve cone (N° 17) or
off-position valve stem (N° 16) damaged
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Replacement of the Spray Gun Components

If a jet contour other than those already described is desired, the spray gun has to
be re-tooled. Air control head, material control nozzle and needle packing together
form a unit - the nozzle insert assembly. Always change the complete insert assem-
bly to maintain the desired spray finish quality.
Warning
Prior to any repairs/replacements: Make sure that the spray gun is in unpressurized
condition, i.e. all air and material inputs must be shut off - if not, imminent Risk of
Injury.
Note
In order to perform the following procedures, please refer to the exploded diagram
(page 2) of these operating instructions.
8.1 Replacement of the material nozzle and the air cap
1. Unscrew the retaining nut (N° 2).
2. Remove the air cap (N° 3).
3. Unscrew the nozzle (N° 4) from the gun body (N° 5).
Reassemble in reverse order.
Remedy
• Clean or replace
• Adjust by turning clockwise
• Top-up material level
• Keep it level
• Fasten or replace
• Deliver with pressure tank or
pump system
• Replace
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8.2

Replacement of the needle

1. Unscrew the spring retaining bush (N° 14).
2. Take off the needle spring (N° 13).
3. Pull the needle (N° 10) out of the gun body.
Reassemble in reverse order. For correct initial air adjustment the needle has to be
set at 76,5 mm measured from the tip to the driving sleeve (N° 11).
8.3 Replacement of the needle seal packing
1. Disassemble the needle as described 8.2.
2. Remove the needle packing gland (N° 23).
3. Remove the needle packing (N° 24).
Reassemble in reverse order.
Note
Never reinstall a used needle seal packing, as otherwise the functional sealing
reliability of the spray gun will not be guaranteed.
Note
All sliding and moveable parts (except the material needle!) must be lubricated with
a non-acidic, non-resinogenic grease prior to installation.
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Cleaning

The gun does not need to be dismantled for cleaning. Clean the PTFE-coated gun
body with a soft cloth.
1. Fill the cleaned material container / gravity-feed cup / syphon-feed cup or the
cleaned pressure tank with a cleaning fluid compatible with the sprayed
material.
2. Operate the spray gun.
3. Do not stop the spray gun until clear cleaning fluid emerges from the nozzle.
The entire system should then be depressurised until the gun is used again.
Clean the spray gun only with cleaning agents which have been recommended by
the manufacturer of the sprayed material and which do not contain the following
constituents:
• halogenated hydrocarbons
• (e.g. 1,1,1-trichloroethane, methylene chloride, etc.)
• acids and acidic cleaning fluids
• regenerated solvents (so-called cleaning thinners)
• paint removers
The above-mentioned constituents cause chemical reactions on electroplated
components, resulting in corrosion damage.
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