Wire feed on MIG welder not working

[SkinnyG]

The welder is a Lincoln 180 MIG. When I pull the trigger, the shielding gas flows, the wire will arc if grounded, but it will not feed. I first checked to see if the wire was bound in the gun. I pulled on it with some pliers and it didn't feel bound anywhere. Then I looked at the roller. I took the clamp off of the wire to relieve the tension on the roller and pulled the trigger; it did not turn. I can squeeze the roller with a pair of pliers and turn it by hand, but it will not turn when I pull the trigger.

So, where do I go from here?

 

[lilredex]

The feed drive roller is motor driven, so probably a wire is loose/broken off or the motor is NFG. Not likely though if you did not see any smoke.

You have to open it up and get in there with a tester (light/meter) to see where the power ends.

A typical set up.....

 

[Mgdoug3]

I had the same problem on a Hobart 125 and it turned out to be the circuit board. I'm thinking I used my multi meter and found out I wasn't getting power to the wire feeder and saw a burnt spot on the board. New board fixed my problem but from what I have read it's a common problem on the 125. It only gets used a few times a year since I'm usually welding much thicker metal.

 

[SkinnyG]

I'll try to get into it one day this week and see what I find. This is an older model, so hopefully replacement parts are available. Otherwise, maybe it's time to upgrade...

 

[SkinnyG]

So, "I'll try to get into it one day this week..." turned into "I'll take a look at it in 13 months."

This weekend I opened it up and pulled the wire feed motor out. I had no voltage at the motor when activating the trigger. I hooked the motor to a 12v car battery and it spun over. The two wires going to the wire feed motor come directly from the circuit board.

Since everything else works, just nothing at the wire feed motor, is it safe to assume that the circuit board is the problem? Anybody know a good source for these things?

 

[larry4406]

I had this same thing happen to mine about 2 weeks ago (Lincoln ProMig 175)

Found this thread linked below and read Post 14 by Metalmagpie (I think he posts here as well). Apparently power to the feed roller comes thru the voltage selector switch. I cycled the voltage selector switch a few times and back in business.
https://www.practicalmachinist.com/...-fab/lincoln-sp175t-wire-feed-problem-231429/

Mine has discrete voltage settings.

 

[DSLTRK]

So, "I'll try to get into it one day this week..." turned into "I'll take a look at it in 13 months."

This weekend I opened it up and pulled the wire feed motor out. I had no voltage at the motor when activating the trigger. I hooked the motor to a 12v car battery and it spun over. The two wires going to the wire feed motor come directly from the circuit board.

Since everything else works, just nothing at the wire feed motor, is it safe to assume that the circuit board is the problem? Anybody know a good source for these things?

IDK how knowledgeable you are on electronics, but can you isolate the circuit for the motor speed control? I imagine you could do a simple continuity test on the passive components , everything but the solid state ics. There's probably a rheostat (the knob) controlled voltage regulator for the drive feed motor.

Also, if your welder is older, chances are the board is potted(covered in resin), which is great for protection, but horrible for repair/diagnosis.

 

[SkinnyG]

I had this same thing happen to mine about 2 weeks ago (Lincoln ProMig 175)

Found this thread linked below and read Post 14 by Metalmagpie (I think he posts here as well). Apparently power to the feed roller comes thru the voltage selector switch. I cycled the voltage selector switch a few times and back in business.
https://www.practicalmachinist.com/...-fab/lincoln-sp175t-wire-feed-problem-231429/

Mine has discrete voltage settings.

This is very helpful, mine is in fact the same machine. I'll mess around with the voltage switch some and see if I have some luck with it.

IDK how knowledgeable you are on electronics, but can you isolate the circuit for the motor speed control? I imagine you could do a simple continuity test on the passive components , everything but the solid state ics. There's probably a rheostat (the knob) controlled voltage regulator for the drive feed motor.

Also, if your welder is older, chances are the board is potted(covered in resin), which is great for protection, but horrible for repair/diagnosis.

I took the outer cover off this weekend, and conveniently there was a wiring diagram on the inside of the cover, but that diagram had no detail of the circuit board itself. I did pull the board out and look it over, though. I didn't see any tell-tale signs of failure (burn marks, etc), which made me leery of dropping $150 on a new board. Hopefully I can fiddle with the voltage selector as described above and get it going again.

 

[gungatim]

I had the same problem on a Hobart 125 and it turned out to be the circuit board. I'm thinking I used my multi meter and found out I wasn't getting power to the wire feeder and saw a burnt spot on the board. New board fixed my problem but from what I have read it's a common problem on the 125. It only gets used a few times a year since I'm usually welding much thicker metal.

exact same issue here. my HH175 board died, it controls the motor.

don't leave your welder plugged in when not using, the repair center said it is common and power spikes can kill the board...

 

[jim keris]

I had my circuit board on my Lincoln 135 plus repaired at York Electronics good price quick service

 

[metaleltr]

Check continuity of the gun trigger. May be a bad switch or broken wire in the gun cable.

 

[SkinnyG]

larry4406 - You called it!
With a wiggle of the voltage selector knob, the wire feed motor started working again! Now I can get back to fixing my trailer. Thanks for the insight, Larry. Saved me some money and lots of frustration I'm sure!

 

[larry4406]

larry4406 - You called it!
With a wiggle of the voltage selector knob, the wire feed motor started working again! Now I can get back to fixing my trailer. Thanks for the insight, Larry. Saved me some money and lots of frustration I'm sure!

Thanks go to MetalMagPie! I simply found his thread elsewhere and repeated it here after it helped me.

Glad you are up and running again.