12
TROUBLE SHOOTING GUIDE
TROUBLE
CAUSE
REMEDY
Sags or runs
Too much paint.
Gun moved too slowly.
Paint too thin.
Gun held at incorrect angle or too close to
painting surface.
Spray overlaps too much.
Turn the adjust nut counterclockwise.
Move gun faster.
Add unthinned paint to achieve correct time
through viscosity test cup.
Hold gun at right angle to surface and at a
distance of 15-20 cm.
Overlap spray about 1/3 width of spray
pattern.
Dry spray
Insufficient paint coming from the spray gun.
Gun held too far from surface.
Overspray from a preceding section when
gun is not held at right angle to painting
surface.
Spray patterns not well overlapped.
Air cap holes partially blocked.
Turn the adjust nut clockwise.
Hold gun at a distance of 15-20 cm surface or
closer for small objects.
Hold gun at right angle to the painting
surface.
Pay attention to the gun movement path.
Determine if obstruction is on air cap or paint
tip by
making a test pattern, rotating air cap half
turn, and spraying another test pattern. If the
defect is inverted, obstruction is on air cap.
Spitting or
spraying
lumps
Solid particles in paint.
Downward spraying angle more than 90°.
Strain paint.
Do not downward the angle too much.
Motor is
running but no
spray
Paint not thin enough.
Check Valve dirty.
Air partition cap missing/dirty.
Loose paint container.
Lid washer missing/dirty.
Motor is running but the trigger
does not pull the needle.
Loose needle.
Low volume of paint from spray gun.
Paint or glue causes needle to stick, so
trigger cannot pull it.
The needle tip drops from the needle, so
needle tip is jammed tight in spray tip.
Obstruction on paint tip or dirt on air cap seat
or paint tip seat.
Add the appropriate amount of solvent to the
paint. Add only a small amount of solvent to
the paint at one time.
Clean check valve.
Replace/clean air partition cap.
Tighten paint container.
Replace/clean lid washer.
Increase pressure on the trigger to pull
needle to shoot paint out.
Tighten needle.
Turn the adjust nut clockwise
,
the release
amount becomes bigger or Clean spray tip &
needle to restart the trigger.
Clean spray tip & needle.
Take out needle tip and install needle tip in
the needle.
Clean air cap with non-metallic instrument. If
obstruction is on paint tip, check for fine
burring which can be removed with 600 wet
or dry sandpaper. For dried paint inside, open
and wash.
Fluttering
spray
Jamming needle.
Needle nut not seated properly.
Blocked paint passages or Slide pipe not
seated properly.
Loose slide pipe & switch spring.
Pull and then release trigger quickly (2-3
times) to make sure needle is seated
properly.
Tighten needle nut.
Clean paint passages or Lubricate slide pipe to
make
sure slide pipe is seated properly.
Ensure slide pipe has to clasp spring
properly.
Paint leaking
from the paint
container
Loose paint container.
Loose lid washer or worn lid washer.
Tighten paint container .
Tighten lid washer or replace lid washer .
Paint leaking
from the
nozzle
Loose nozzle.
Needle nut is too tight, so the needle not
seated properly.
Tighten nozzle.
Loosen needle nut.