Yeswelder MIG-250PRO Operator's Manual page 33

PROBLEM
Work clamp, ground
cable, and/or welding
cable get hot.
Gun nozzle arcs to work
surface.
Feed motor operates
but wire will not feed.
Wire is "bird-nesting" at
the drive roller or
jamming.
Wire burns back to
contact tip.
Difficult arc start.
Arc is wandering (TIG).
POSSIBLE CAUSE
Bad ground or loose ground connection.
Spatter or Slag build-up inside nozzle or
nozzle is clogged.
Insufficient feed drive roller pressure.
Burr on end of wire.
Liner blocked or damaged.
Despooler tension too high.
Too much pressure on drive roller.
Contact tip is clogged or damaged.
Worn guides or drive roller alignment.
Wire feed speed is set too low for voltage
setting being used.
Stick-out too short.
Wrong size contact tip.
Contact tip is clogged or damaged.
Amperage is too low.
Make sure base metal is clean.
Make sure electrode is not damaged.
Tungsten is too large.
Gas flow is too high.
POSSIBLE SOLUTION
Check the connection of the
the machine. Check the connection of the MIG
ELECTRODE POLARITY JUMPER. Check connec-
tion of the ground cable to the
cable connection to
the connection between the
workpiece is good and on clean, bare (not painted
or rusted) metal. Make sure cable is not damaged.
Clean or replace nozzle as needed.
Adjust drive roller pressure.
Re-cut wire so it is square with no burr.
Clear with compressed air or replace liner.
Adjust despooler tension.
Adjust the drive pressure. See "Installing The Weld-
ing Wire".
Replace contact tip.
Replace parts.
Increase wire feed speed.
Increase stick-out (the amount the wire extends
past the contact tip).
Use correct size contact tip.
Replace contact tip.
Increase amperage setting.
Properly clean base metal.
Replace electrode if needed.
Use a smaller tungsten.
Reduce gas flow.
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work clamp and gun to
work clamp. Tighten
work clamp if needed. Ensure
work clamp and