My old murex is causing a few problems. Intermitendly it will stop feeding wire to the gun, no contactor kick in nothing. It has a awitch for continuous, stitch and spot. With a multimeter I am getting 13v dc at euro connector for both both the continuous and stitch and 36v dc when the switch is moved to spot - is this normal? When the welder stops working there is no voltage for continuous or stitch but still 36v dc for spot. If I move the switch to spot and arc the welder and move the switch back to continuous it will work again. Could this be as simple as a faulty switch? Any help would be appreciated.