to
TM
5-3431-221-15
for
c. R e f e r
NOTE
Before you use this table, be sure you have
troubleshooting that concerns the welding machine.
performed all applicable operating checks.
TM 9-2330-202-14P
for
d. R e f e r t o
troubleshooting that concerns the trailer chassis.
MAINTENANCE OF WELDING GUN AND CONTROL MONITOR
Section IV.
c. Maintenance of Welding Gun and Control
Monitor.
a. General. Maintenance at this level is
(1) As the gun is used, a small amount of
restricted in that virtually no disassembly is at-
spatter will collect on the end of the guide tube and
tempted. Primarily the maintenance will consist
on the nozzle. This spatter can be removed easily
only on inspecting, servicing, and adjusting the
with a knife or some other similar implement.
equipment.
Periodically, remove the nozzle by pulling it from
b. Adjustment for Welding Gun.
the nozzle holder and inspect the nozzle and gun
(1) Wire brake. Refer to paragraph 2-2 d (3)
barrel for spatter which may have collected inside.
of this manual.
Excessive spatter can cause a short between the
(2) Rheostat. Turn the rheostat knob clock-
nozzle and the guide tube. Such a short will create
wise to reduce speed.
an arc between the nozzle and the work piece if
(3) Guide tube. Refer to paragraph 2-2 d (1)
accidental contact is made.
of this manual.
Table 3-2. Troubleshooting
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
WELDING GUN
1 . WELDING GUN WILL NOT WELD.
Step 1. Check to see if the control monitor power switch is in "OFF" position.
If prover switch is in "OFF" position, turn it to "ON" position (para 2-1 b ).
Step 2. Check connector at control monitor to see if it is making contact.
Disconnect receptacle and inspect for corrosion.
Clean contacts as necessary and connect it back up,
making certain the receptacle is tight.
Step 3. Check connector at weIding machine to see if it is making contact.
Perform same corrective action given in step 2 above.
Step 4. Check to see if argon valve is off.
Turn valve on and adjust to desired pressure (para 2-1 b (2)).
Step 5. Check to see if argon bottle is empty.
Replace bottle if necessary (para 3-8).
Step 6. Check to see if wire is feeding, if not it is probably kinked.
Open swing arm and manually feed the bent wire through the tube
until straight wire is properly aligned with drive wheel.
2 . CUTTING TORCH WILL NOT OPERATE PROPERLY.
Step 1. Check to see if cutting tip is clogged.
Remove tip and clean obstruction from it (para 3-8).
Step 2. Check to see if oxygen or acetyline is off or not set properly.
Turn valves on and/or reset to proper pressure for the job at hand (para 2-1 b (3 )).
(2) If the guide tube becomes bent, replace it
the wire about 1/16 inch from the rear of the
with a new guide tube. If a burn-back occurs, do
guide tube. Hold the guide tube perpendicular to a
not inch the wire. "Attempts to inch the wire under
hard, flat surface, and strike the end of the wire
these circumstances will blow the fuse in the control
against the flat surface. If this does not free the
circuit. When a burn-back occurs, loosen the
wire, cut or grind off the melted portion of the guide
thumbscrew which secures the guide tube, and inch
tube and remove the wire. The burr caused by
both the wire and the guide tube out of the gun. Cut
cutting should be removed from the guide tube hole
