Need Welder Help

[ksp04031]

Well, I left my welder (Lincoln 175HD) at the firehouse, which is the equivalent to leaving my welder with a bunch of toddlers on crack. Needless to say, it doesn't work anymore. I already looked over the obvious connections, polarity, cleanliness, liner and tips and it all checks clear. As soon as you pull the trigger, it arcs at the tip of the liner where it plugs into the unit behind the drive assembly, which is fusing the wire to the liner. I've run quite a few spools of wire through this thing and never had this problem. I'm searching, calling and reading about how to fix it, just thought I'd post up and see if anyone else has had this problem before. Thanks for reading.

[Wyoming9]

If you have checked the nozzle is the correct one and also that it is not full of metal splatter to short the gun.

The gun or wire drive housing is shorted to the case when you pull the trigger.

I would guess the back end of the gun is installed correct, that could be a problem.

without seeing it in person. There is not much more to check.

You checked that you don`t have a coil of wire off the back side of the spool.:D

[ksp04031]

If you have checked the nozzle is the correct one and also that it is not full of metal splatter to short the gun.

The gun or wire drive housing is shorted to the case when you pull the trigger.

I would guess the back end of the gun is installed correct, that could be a problem.

without seeing it in person. There is not much more to check.

You checked that you don`t have a coil of wire off the back side of the spool.:D

While double checking the unit, I found some arcing and fusing on the braided copper strap on the grounding clamp. This is new. Any ideas? Beuller? Thanks for your help wyo9