millermatic 250 liner problem.

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I have a millermatic 250 that has been giving me some grief with its wire feeding. I’ve noticed varying wire speeds and sputtering at the weld-point. I’m running argon/co2 mix that is known to be good. Since the welder is a used CL buy I figured the liner was kinked. When I pulled it out to check it, the liner looked new and I didn’t notice and damage. What’s weird is that the input side of the liner has a threaded nut attached to the conduit that doesn’t screw into the gun lead. The gun and lead are original to the welder. After going to my local welding shop for some advice the best I could get was for me to buy a new gun and liner, at 400$ I’m not liking that idea.The threaded nut is held down by a cullet of sorts, but the cullet can be screwed down until it bottoms out, so I doubt its forcing contact between the liner-nut and gun lead. Is there a correct liner for my older welder or am I stuck with the choice between buying a new gun and lead or putting up with intermittent electrical connections and sputtering?Thanks!
Reply:I have had liner problems before too.  This sound like a liner problem to me.  Even if it looks new it may have a groove cut in it somewhere.  Liners can go for long periods of time or if rusty wire has been run through it it may not last more than a roll or two.  One more thing to examine is if the cable coming out of the feed rolls or just out of the machine has a sharp bend in it.  Another thing to examine is the wire itself.  The roll may be crossed and bound up.  Also check the tension on the roll.  I don't know what kind of gun you have.  I have used Tweco for years.  I am not recommending any one over another.  The set up you described is unfamiliar  to me.  Some pictures might help.  In the mean time check those few things out.1938 Lincoln SA 600 1973 Lincoln SAE 3001984 Lincoln Sa 250DF800 Ford with 10 ton craneVictor and Harris torches.Rolair compressorSouthbend 13" latheAtlas Mill
Reply:If you actually need an entire new gun, you can buy Bernard guns on E-Bay for $100-200, brand new and complete...
Reply:You have the right liner, Miller made one liner to fit two different style guns.One with a cap and no threads and the other with threads and no cap.All the M guns use the same liners. The real old GA gun uses a different liner.The only reasons to replace a miggun are, shorted trigger wires, the gun is just falling apart.open weld conductor. Some wrong with the gas hose, leaking or swelling that seals off gas flow. Have seen some really bad looking guns that still worked fine.
Reply:Just an FYI, you can get a 300 amp Bernard center fire gun on eBay for less than 150.  It's a much nicer gun than Millers IMHO and the parts are really available for cheap.TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:I have a Miller 22A wire feeder on a Shopmaster power source at work and it has never fed smooth from day one. Tried different liners, new gun, adj tension on the spool, it will still randomly stop feeding then start just as you flip your helmet to see whats going on.......very frustrating. And, it seems to come and go.......ugh....