Hi. This is my first post. I have an nbc mig 140 which I am using to repair my series 2 landrover. The other night the welder was switched on but not welding and I heard a pop from inside the machine like a fuse blowing. The welder still switches on but the wire does not feed or go live and there is no gas at the torch. Im looking for some advice on what the problem might be. Thanks.