TM 43-0139
b.
Air Leakage from Front of Gun. This condition is caused by the air valve not seating properly due to:
(1)
Foreign matter on the valve or seat.
(2)
A worn or damaged valve or seat.
(3)
A broken air valve spring.
(4)
A sticking valve stem due to lack of lubrication.
(5)
A bent valve stem.
(6)
A tightly closed packing nut.
c.
Material Leakage from Front of Gun. This condition is caused by the fluid needle not seating properly due to:
(1)
A worn or damaged fluid tip or needle.
(2)
Lumps of material or foreign matter lodged in the fluid tip.
(3)
A tightly closed packing nut.
(4)
A broken fluid needle spring.
(5)
An improper size needle.
d.
Jerky or Fluttering Spray.
(1)
In pressure or suction-feed guns, this condition is caused by air leakage into the material line due to:
(a)
A lack of sufficient material in the container.
(b)
Tipping the container at an acute angle.
(c)
An obstructed fluid passageway.
(d)
A loose or cracked fluid tip in the cap.
(e)
A loose fluid tip or damaged valve seat.
(2)
Conditions which apply only to suction feed are:
(a)
Material being too heavy for the suction feed.
(b)
A clogged air vent in the container lid.
(c)
A loose, dirty, or damaged fluid inlet connection.
(d)
The material feed tube (see figure 5-7) is resting on the bottom of the container.
5-9
