I have a hobart 135 mig welder. When the trigger is not depressed the gas valve is still open and I can still strike an arc. It appears like a relay is stuck on the circuit board. Please give your opinion

Make sure the trigger switch is applying power to the motor. If there is no reading when you checked for OHMS then the motor is open. You'll have to get a new one.

Does it just do it once for a short time each time the machine is plugged in? If so, don't worry about it.

lp

Have you checked the trigger inside the gun to make sure it is not stuck?

The main control circuit for the welder has gone bad....cost about $198.
Might be better off to buy a new welder.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/sean_54c3a3dc48a7773c

You do not indicate if the wire is already out of the nozzle. If not, commonly the wire can jab the side of the tube it runs through and cannot advance.

IF the wire is already threaded, then there MAY be a fuse to protect the motor.

The click MAY be the gas valve, or the relay driving the motor and/or the main transformer for welding current. The circuitry for these is relatively simple and a voltmeter is your friend to troubleshoot this.

Make sure selector switch is not in between settings, this is where the wire feed voltage comes from.

if you have a airgas dealer they carry hobart parts im not sure why you are blowing circut brackers unless they arenot big enough

Sounds like the trigger is getting worn out.

does it have a reset button? if so it has gone bad, if not there is a fuse or something inside. they protect that circuit against shorting at the working end of the gun. happens ALL the time.
Hawk

It doesn't take much to jamb the solinoid , too much presure on the argon will hold this open, turn the gas off, purge the line, release the pressure on the regulator, Now turn the gas on and put approximatley 2-3lbs only on the gauge, turn the flow meter for a reading of 15-20ltr/min, then try again,