E-2
MAINTENANCE
INNERSHIELD PRO & MAGNUM CLASSIC GUN
Observe all Safety Guidelines detailed throughout this manual
If for any reason you do not understand the procedures or are unable to perform the maintenance or repairs safely, contact your
Lincoln Authorized Service Facility for technical troubleshooting assistance before you proceed.
WWW.LINCOLNELECTRIC.COM/LOCATOR
PROBLEMS
(SYMPTOMS)
POSSIBLE
CAUSE
RECOMMENDED
COURSE OF ACTION
No wire feed occurs when trigger is pulled.
1. Machine is switched off or unplugged.
1. Switch on or plug in machine.
2. Out of wire
2. Install full spool of specified wire.
3. Contact tip burnback.
3. Replace contact tip.
4. Fully or partially blocked gun liner.
4. Remove and clean or replace gun liner .
5. Bird nest
5. Cut out bird nest, reload wire, and check
for proper wire alignment.
6. Defective trigger (contacts open or dirty).
6. Replace trigger assembly.
7. Defective trigger circuit in gun.
7. Disconnect gun from machine and check
trigger circuit for continuity.
8. No motor voltage or current from
machine.
8. See Troubleshooting section in welding
machine’s or wire feeder’s instruction
manual.
9. Contact tip size too small for wire
diameter used.
9. Replace contact tip with one that is the
correct size.
Sluggish wire feed when trigger is pulled.
1. Drive roll is worn or galled.
1. Clean drive roll or replace drive roll.
2. Machine’s wire feed speed setting is too
low.
2. Increase wire feed speed.
3. Wire is obstructed somewhere along the
wire feed path in the gun.
3. Check for obstructions: Remove any wire
shavings; remove kinked wire; remove
and clean or replace gun liner.
4. Low motor voltage.
4. See Troubleshooting section in welding
machine’s instruction manual.
5. Gun cable is coiled/kinked.
5. Remove all sharp curves from gun cable
while welding.
6. Mechanical resistance to wire feeding is
too large
6. If using a reverse bend gun tube, try
welding with a non reverse bend product.