Hi ive got a 4yr old sealey 130 xt.v2.Its had very little use since i bought it.Im having trouble with the wire feed.it doesnt speed up or slow down when i adjust speed control and the motor is very juddery.its been removed from the welder and Ive tried a multi-meter on the 2 wires that connect to the motor itself for voltage and ohms.both times the readings rose and fell as i turned the feed control up and down.also i connected the motor to a 12v battery charger and it works perfectly,spins fast and no judders.i know there is a few posts up about the motors not working at all but i couldnt find any with this problem.Any info on this would be great,thanks