Lincoln Electric MAGNUM 300FM - Manual (Page 14)

MAINTENANCE
CABLE REPAIR
The Magnum® 300 FM and Magnum® 400 FM guns
feature the use of repairable cable connectors. If the
cable ever gets severely damaged, it may be cut short-
er and repaired by the user. Repair cables as follows:
Gun Tube End Repair (K478 and K479) (Requires 2
#S19492-2 Terminals)
a) Remove the cable liner per “Removal Instructions
for Magnum® Liners”.
b) Remove the gun tube per “Gun Tubes and
Nozzles“.
c) Remove three #6 screws from the gun handle, sep-
arate the two halves, and remove the cable from the
handle along with the trigger assembly.
d) Remove the gun tube connector from the cable by
unscrewing the connector nut from the gun tube
connector. If the cable inner tube is difficult to
remove from the connector assembly, carefully slit it
lengthwise with a knife up to the brass connector.
e) Uncouple the strain relief by pushing its outer hous-
ing toward the middle of the cable. Move the strain
relief and the cable boot toward the middle of the
cable, past the damaged section.
f) Cut off the damaged section of the cable and strip
off the outer jacket as shown in Figure E.2. Be care-
ful not to cut the insulation on the control wires while
stripping the jacket. Strip the red and white control
leads 1/4 inch (6.4 mm) from the end and crimp a
new S19492-2 terminal to each lead.
NOTE: The cable contains three control leads. Any
two control leads can be used, provided the two col-
ors used are the same at both ends. The extra lead
is a spare that can be used if one of the other leads
breaks.
g) Check that the cable boot and both halves of the
strain relief are on the cable. Slip the connector nut
over the copper strands with the thread end out.
Orient the gun tube connector so the machined flat
is on the same side of the cable as the red and
white control leads. Assemble the gun tube connec-
tor to the cable by forcing the steel tube of the con-
nector into the inside diameter of the cable inner
tube until the copper strands are butted against the
gun tube connector shoulder. Keeping the copper
strands against the shoulder, pull the connector nut
over the copper strands, engage the gun tube con-
nector threads, and tighten in place. Refer to Figure
E.3.
NOTE: For best results, insert a rod through the
connector and into the core of the cable approxi-
mately 5.00” (127 mm) when pushing the connector
tube into the cable core tube. A .219”/.240” (5.6-6.1
mm) diameter rod is required for 300 and 400 amp
cables. To tighten, hold the connector in place while
turning the nut, then remove the rod from the core.
This procedure assures the inner core does not kink
while assembling or tightening.
h) Pull the cut-off lead terminals off the trigger assem-
bly and connect the replacement control lead termi-
nals.
j) Position the cable boot and the strain relief on the
cable so it fits in the cable handle cavity and lock
the strain relief in place by pushing the two halves
together.
k) Assemble the cable in the left side of the gun han-
dle. Assemble the trigger into the proper handle
cavity. Assemble the right side of the gun handle
and tighten the three screws that hold the handle
together. Refer to Figure E.4.
l) Install the gun tube per “Gun Tubes and Nozzles“.
m) Install and trim the liner per “Liner Installation and
Trimming Instructions”.
Wire Feeder End Repair (K478 and K479 FM Models
Only)
a) Remove the cable liner per “Removal, Installation
and Trimming Instructions for Magnum® Liners”.
b) Loosen the boot nut. Slide the boot nut and boot
toward the middle of the cable past the damaged
section.
c) Rotate the collar nut until the screw anchoring the
cable handle is visible. Remove the screw and save
it.
d) Slide the cable handle, collar nut and strain relief
housing toward the middle of the cable past the
damaged section. On older cables remove and
save the cable clamp that was used in place of the
strain relief.
NOTE: If sliding the cable handle becomes difficult,
try rotating it 180°.
MAGNUM® FAST-MATE™
D-3 D-3