Lincoln sp 175t. drive motor does not turn and no arc. when i pull trigger i hear a click like it has always done but no arc or wire feed. have checked for proper voltage and pressed reset on back of welder. removed wire and tension from roller and still nothing.last used a week ago and everything was working fine.today nothing.

There are several things that could cause this:
1. The relay (contactor) that switches on the arc is not closing and it could be bad.
2. The diodes in the power supply are bad.
3. The low voltage transformer is bad.

Hi:
If your wire feed motor turns, then your problem is one of the two:
The gun's liner is kinked and no longer is allowing the wire to pass freely, or Your outlet wire guide/drive rolls are all worn out.
Easy fix will be to star with changing the liner and new contact tip. But if all that is working is your fan motor, then check your gun's trigger, if gun's trigger is OK, then change the pc board. Good luck!

Your drive tension is too light. There are rollers that the wire feeds through and they need to be tightened. They should push the wire through the gun but slip if you put the tip against a solid object and pull the trigger. If they do not slip, they will jam your gun. Give the tensioner another turn.

i believe that the trigger only send out the wire and does not control the arc the tip should be live as long as the welder is on

open the area were the role of wire is and check when trigger pulled if any action to feed motor. [wire might be stuck at end, or there usually is a small fuse in that area for feed motor]

Maybe you can get lucky like I did . Some times the acr volt selector switch gets corrosion in it and wont let the circuit board know to send power to the wire feed motor. You can cycle this arc volt. switch in my case it is the a,b,c,d,e, switch back and fourth a few times and this will brake the corrosion and your wire might feed again as mine did . This corrosion build up happens from not using and or sollecting the switch much usually on a welder at hm that gets very little use. it is common good luck .

Either the trigger mechanism in the gun is bad, the servo that turns the feed wheel is bad, or you have too much tension on the adjustable tensioner knob. Take the wire out of the feed wheel, plug unit in and see if you can get the wheel to turn. If not, it is the trigger or the servo. If it turns, the tensioner was too tight.

not diode problem,check enternal wiring and relay for feed motor.

check for power to drive motor,if power is there when you pull gun trigger then motor is bad.if no power look for bad wire connections then relay.

you are going to need to remove the wires going to the wire feed motor, then take a volt meter and check the wires when you pull the trigger. this will tell you if the motor is bad or another problem