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Troubleshooting, Caution – Lincoln LN-742H User Manual

Page 39

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E-6

TROUBLESHOOTING

E-6

LN-742 & LN-742H

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

(SYMPTOMS)

POSSIBLE

CAUSE

RECOMMENDED

COURSE OF ACTION

The wire is feeding rough or not
feeding. The drive rolls are turn-
ing.

The drive rolls do not turn when the
gun trigger is pressed. The gas
solenoid activates and arc voltage
is present.

1. Check for mechanical restric-

tions in the wire feeding path.
Check the gun and gun compo-
nents.

2. Check the drive roll position and

idle roll pressure.

3. The electrode may be dirty or

rusty.

4. Check for the correct gun liner,

tip, and guide tubes.

1. Check plug J5 on the control

board for loose or faulty con-
nections.

If all recommended possible areas of
misadjustment have been checked
and the problem persists, Contact
your local Lincoln Authorized
Field Service Facility.

This manual is related to the following products: