Miller Syncrowave 250 gas leak and HF start issues

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Hi all,I purchased a used Syncrowave 250 with watercooler a few months ago and I’m just now trying it out. I’m a novice to TIG welding but off the bat I’ve noticed a couple of issues with the machine.First off, there is a slow gas leak from the torch tip before and after the solenoid engages. Doesn’t affect welding but wastes gas. So before pre-flow and after post-flow there is a constant stream of low flow gas from the torch. Could this be a solenoid issue? Or debris blocking solenoid? I blew out the new argon tank just prior to screwing in the regulator.Second issue is the high frequency start doesn’t work reliably and I end up having to touch the filler rod to the workpiece to initiate an arc - to clarify, I’m not touching the tungsten to the workpiece, just the filler rod to the workpiece so I don’t think this is the same as scratch start. I don’t mind I guess, but could this be a point gap adjustment issue on the HF start or some other issue?Thanks!
Reply:If gas is flowing out the torch with no power to welder. something is holding gas valve open. Sometimes the valve can be disassembled and cleaned. Be careful to not loose springs or other valve parts. On the HF. you need to remove one of the spark gap points(electrode) and inspect it. if it is pitted and worn they should be replaced.Factory does not recommend resurfacing. But you can try cleaning with a wire brush wheel. Then set gap to0.008 to 0.009 if it is not to pitted. The pits change the dynamics of the arc and it won't make HF correctly. Sometimes the points collect dust and metal dust and oxides and they also cause problems.I have ahd a couple of welders that you had to rest the cup or tap the tungsten to work between arc starts or it would not fire. points had an oxide coating and would not spark right. You also need to check C13 and C14. one goes from the work terminal to case ground the other cap goes from case to the HF coupling transformer/inductor. This is the return path for the HF.  HF jumps from the tungsten to work then returns up the work lead to the welder through the capacitors and back to the coupling transformer.The spark should crackle not buzz. If it sounds like a neon light you have a bad HF cap.