Fix a Mig welder your guide to troubleshooting a MIG welder (any brand) not working or broken 

Too easy mate.

Thanks David

No worries Rich

I'm very happy you got it fixed. Thanks mate

That's the way

Yeah, it is very possible for the transformer to fail. If the connections are good, that could be the case for you unfortunately.

@Will Swift Thanks for your video with simple explanations. To be honest I still don't find where exact cause of the problem as the machine was new and every part looked OK. I mean in visually concern. May be I don't know how to use it. But you video gave me a lot of knowledge about MIG welder and thanks again.

Hi. The thing you might need to replace is called a Welder Rheostat. www.amazon.com/gp/search?ie=UTF8&tag=unfastened-20&linkCode=ur2&linkId=95edf9d2734649a4b585eebb49f7d7e4&camp=1789&creative=9325&index=electronics&keywords=welder_rheostat That link will take you to Amazon. Just open the welder up and see what type it is and you should be able to find it from that link. It might be a plug in one, or soldered in. Unsolder the old one, solder in the new one and it should work.

Everything and just a tip welders can hold power after being turned off so if u are going work on it turn it off and let it sit for 15 minutes.

I reckon you might have a blockage, Barry. If a piece of mig wire fits up the gas line, feed a piece from the handle all the way through to the machine end (with the machine end undone). If it isn't that, you'll need to check the pipe going from the gas pump through to the handle connection on the machine. Good luck

@@Unfastened Thank you, the gas flow is ok and comes out of the gun ok but the pressure builds up and blows off the connection to the welder case. I have asked Snapon but they do not recognise the model Promig 150. I think the regulator is faulty but need someone who knows these things before I buy one.

What sort of welder? If you contact the manufacturer they can usually just supply the control board. When you hit the mig gun switch, the control board will be delivering 24v (depending on the welder) to the wire drive motor. If the wire drive motor works fine off other power sources, then the 24v delivery from the welder is the issue. Replace board, or if it has a separate inverter board that is converting AC to DC that might need replacing.

@WilliamHelstad Rusty wire will do that as well, ( hazard of living in the tropic's. )

I have what I believe ends up being a vevor 280amp multi use unit. It broke a while back and did the same thing with the motor. It blew some MOSFETs which I replaced but there's somethig else holding it up now. I got it through some Chinese distributor that avoided me when I tried to get the warranty honored. So I take a look at it here and there. I have a yes welder now so I don't out too much effort in fixing it. Although it was 6 months old when it blew so it would be nice to get running again.

Take the trigger switch apart. I'd say the switch would be faulty, causing the machine to think you are consistently holding the trigger down, when you are not. If it is not that, you need to check the wiring going to the wire feed rollers. Perhaps a worn wire would trigger the feed to stay on. Good luck

@@Unfastened I contacted the supplier, sent a video and they were more than happy to replace the machine. Waiting on delivery... thank you for the advice, will definitely keep it in mind if I encounter similar problem in the future.

Normally it won't turn on if the fuse is blown. Some will turn on, but then they won't weld / arc.

@@Unfastened that happen to me. My mig can turn on.but there is no spark so cant weld.