View Full Version : Hobart 140 feeds wire on it's own ???

12-29-2007, 06:34 AM
My hobart 140 mig, is possessed!:blob4:

I think I have something wrong inside the gun.... When I'm done a weld, and move the gun away, to either set if down, or sometimes when I pick it up. I hear it click in, and it starts to run wire when I'm NOT pushing the trigger. or anywhere near the trigger, If I wiggle it around it stops, but then sometimes with the slightest movement it will start again. Anyone have any ideas, or seen this type of problem before? It's actually a Miller gun, (written right on the side of it). I can't see how I would take it apart to find out why it's activating the feed when the trigger is not pushed. Can they be taken apart? Any help or suggestions of what to do with it would be appreciated.:confused:

12-29-2007, 07:27 AM
Yeah, the gun can be assemblied to get to the switch and wiring in the handle.

If you look directly at the neck end of the handle, you should see the wording "TO REMOVE" with a couple of arrows pointing in the direction to rotate the handle locking nut. This nut only rotates about an 1/8 of turn in the direction the arrows indicate, then it can be pulled forward towards the nozzle end of the gun neck. No tools are required to do any of this, you should be able to perform this task by hand. To better understand which part of the gun is considered the handle locking nut, take a look at the exploded view of your H-10 gun, provided to you, in your owners manual. In the OM that I have, this is on pg. 41 figure 10-2. The locking nut is item number 6.

12-29-2007, 07:31 AM
Thanks, I'll check it out later today when I get up. (working nights right now)

12-29-2007, 08:20 AM
OOPs, it was suppose to be disassembled. This site won't let me edit it now though.

12-29-2007, 08:34 AM
That's ok.... I new what you meant. Sometimes the brain just can't stay with the fingers.... or vice versa...

12-29-2007, 11:10 PM
This happened at work just the other day. The trigger spring had broken in half and was no longer pushing the trigger back away from the microswitch, so the switch was staying on after releasing the trigger. Jiggling the trigger would stop it, and start it back up too. Replacing the spring fixed the problem.

I have had this happen on my torches too. Once, it turned out the handle and trigger were binding on eachother, causing the trigger to keep pushing on the microswitch after being released. A burr was causing the problem and a quick filing of the plastic fixed it.

I have also had one of the microswitch wires get caught up between the housing and switch after re-assembling a torch I took apart for other reasons. The wire made contact with the other pole on the switch, closng the circuit without action from the switch.

Fortunately, gun problems are usually easy to fix. :)