Welder wierdness

[KLF]

Went to give my son a hand today with the SAS on his 4Runner. He's been using a Hobart 140 Handler, and has done quite a bit of welding over the last couple of weeks. We decided today that the front hanger needed to be relocated, so I cut the tack welds and re-positioned. The welder will only make these terrible sputtering welds, like pop pop pop pop... rapid frequency but not normal. My first thought was a bad ground, but we did everything we could think of and it wouldn't improve. At one point we were just working on a piece of scrap that he had used for practice earlier, and it was a no go. I checked all the connections I could even inside the machine. I also tried a few other voltage and speed settings, didn't help. We swapped over to a different bottle of gas (25/75) and it also didn't help. I can hear the gas hissing out of the gun.

Any ideas? He's kinda stuck at this point, needs to get this figured out.

 

[PAToyota]

Sort of sounds like what happened when I burned out a diode on my Century 110V MIG. A set of new diodes was pretty inexpensive and an easy replacement.

 

[rusty_tlc]

How is the wire feed?
Sometimes if the feed wheels ares slipping or the wire is binding they will act like that. I had to replace the feed driver circuit board in the Handler I borrowed to do my SOA, pretty much the same symptoms.

 

[spressomon]

^ Most hobbyist welders IMO don't swap out their mig gun liners often enough. I had a similar problem a few months ago and installed a new liner and the MM252 runs like new again. And they're not very expensive: < $25 typically.

 

[41magsnub]

Also, how is the tip? Have you replaced that lately? My MM212 was doing about what you describe and that was the issue.

 

[Bogo]

Also, how is the tip? Have you replaced that lately? My MM212 was doing about what you describe and that was the issue.

Could also be the wrong tip hole size for the wire size.

 

[shotgun]

did you change the wire gauge and not change the drive wheel ?

 

[KLF]

Sorry for not keeping better track of this thread. We figured it out. Mixed communications, I was reading the wrong row on the table on the door, wire speed was too high. Tip was brand new, correct roller, it was an OE issue. All set now, thanks.