C12, TM 9-2350-230-12
TABLE 8-4. TROUBLESHOOTING - CONTINUED
Malfunction
Probable cause
Corrective action
GUN-LAUNCHER- Cont
125.
Breech mechanism
c. If closed and will not open,
c.
Replace, if defective
fails to operate
breech-open limit switch
(fig 11-12).
electrically -
LS4 (right side) is defective.
Continued
d. If open and will not close,
d.
Replace, if defective
breech-closed limit switch
(fig 11-12).
LS2 (left side) is defective.
e. Seized breech chamber and/
e.
Notify support maintenance.
or breech mechanisn.
126. Motor runs but
Inspect plunger for sheared
breech fails to
plunger or plunger bushing
teeth; bushing to be certain
operate
plunger slides freely. Inspect
place defective components.
127. Breech mechanism
a. Insufficient voltage at power
a.
Use fully charged batteries
sluggish in electri-
source
or start vehicle engine
cal operation
(1000-1100 rpm) to assure
adequate operating voltage
b.
Dirt or foreign material on
b. Clean breech chamber and
breech chamber surfaces
exposed surface of spindle
and/or spindle assembly
assembly. Apply light coat-
ing of lubricating oil
c.
Clogged porous vent plug in
carrier cover
d. Breech mechanism binding
c. Remove vent plug and clean
-
(fig 11-25)
127.
Smoke and/or
Failure of seal; erosion or
d. Notify support maintenance
corrosion of detent assembly
from tube lock key
or cannon detent hole
Type 1 detent (para 3-3. 4)
or detent assembly
Remove/install - fig 11-22
vent
Inspect and repair - fig 11-23
Type II detent (para 3-3. 4)
Remove/install - fig 11-23 .1
Disassemble/assemble -
11-23.2
Inspect and repair - fig
For removal and inspection of
Type III detent assembly, notify
128.
a. Detent release lever set-
supporting maintenance
does not function
screw out of adjustment
b. Tip of detent worn or broken
a
Adjust detent release lever
setscrews (fig 11-23, 23.3)
c. Worn or defective actuating
b.
mechanism
23. 1)
c. Inspect for smooth operation .
d. Detent restricted by defec-
Replace worn or defective
tive gas seal in breech
components
coupling (MB1 Mod only)
d. Replace seal (fig 11-22)
8-41