Lincoln Electric IM990 MAGNUM PRO 350 and 550 FUME GUNS - Manual (Page 23)

E-2 TROUBLESHOOTING E-2
MAGNUM™ PRO 350 and 550 FUME GUNS
Observe all Safety Guidelines detailed throughout this manual
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your Local
Lincoln Authorized Field Service Facility
for technical troubleshooting assistance before you proceed.
CAUTION
PROBLEMS
PROBLEMS
(SYMPTOMS)
POSSIBLE
CAUSE
RECOMMENDED
COURSE OF ACTION
No wire feed occurs when trigger is
pulled
Sluggish wire feed when trigger is pulled
1. Machine is switched off or unplugged.
2. Out of wire.
3. Contact tip burnback.
4. Fully or partially blocked gun liner
5. Bird nest.
6. Defective trigger (contacts open or
dirty).
7. Defective trigger circuit in gun.
8. No motor voltage or current from
machine.
9. Contact tip size too small for wire
diameter used.
1. Drive roll is worn or galled.
2. Machineʼs wire feed speed setting is
too low.
3. Wire is obstructed somewhere along
the wire feed path in the gun.
4. Low motor voltage.
1. Switch on or plug in machine.
2. Install full spool of specified wire.
3. Replace contact tip.
4. Remove and clean or replace gun
liner, (See Maintenance Section).
5. Cut out bird nest, reload wire, and
check for proper wire alignment.
6. Replace trigger (See Maintenance
Section)
7. Disconnect gun from machine and
check trigger circuit for continuity.
8. See Troubleshooting section in weld-
ing machineʼs or wire feederʼs instruc-
tion manual.
9. Replace contact tip with one that is the
correct size.
1. Clean drive roll or replace drive roll.
2. Increase wire feed speed.
3. Check for obstructions: remove any
wire shavings; remove kinked wire;
remove and clean or replace gun tube
liner (See Maintenance Section ).
4. See Troubleshooting section in weld-
ing machineʼs instruction manual.