Testing For A Shorted Nozzle; Preventive Maintenance; Troubleshooting - Craftsman 934.205592 Operator's Manual

A SHORTED nozzle results when
spatter buildup bridges the insulation in
the nozzle allowing welding current to
flow through it as well as the contact tip.
When shorted, a nozzle will steal
welding current from the wire whenever
it contacts the grounded work piece.
This causes erratic welds and reduced
penetration.
In addition, a shorted nozzle overheats
the end of the gun, which can DAMAGE
the front-end of the gun.
A RESTRICTED nozzle is created when
enough slag builds up in the nozzle to
affect the direction, concentration, and
or rate of the shielding gas flow. This
problem can cause porous, brittle welds
and reduce penetration.
TESTING FOR A SHORTED
NOZZLE
Arcing between the nozzle and the work
piece ALWAYS means the nozzle is
shorted, but this can be hard to detect
through the lens of a welding helmet.
The following testing method is another
way to tell if a nozzle is shorted.
With the welder unplugged from the ac
power source, touch the probes of an
ohmmeter or continuity tester to the end
of the contact tip and the outside of the
nozzle. If there is any continuity at all,
the nozzle IS shorted. Clean or replace
as needed.
PREVENTIVE MAINTENANCE
Except for internal and external
cleaning, cleaning the nozzle, and
occasionally retightening screws, there
is no periodic maintenance
recommended for your welder.
TROUBLESHOOTING
The following TROUBLESHOOTING
information is provided as a guide to
help resolve some of the more common
problems that could be encountered.
Table 3 is a troubleshooting table
provided to help you determine a
possible remedy when you are having a
problem with your welder. This table
does not provide all possible solutions,
only those possibilities considered to
likely be common faults. The table
consists of a TROUBLE or symptom, a
POSSIBLE CAUSE for that symptom,
and a POSSIBLE REMEDY for that
symptom.
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