No announcement yet.

Millermatic 35 porous welds

  • Filter
  • Time
  • Show
Clear All
new posts

  • Millermatic 35 porous welds

    Hi all!
    Frustration here with a Millermatic 35 Serial JH298130, funky porous welds, thinking it's maybe a shielding gas problem. Unfortunately the Miller Owner's Manual OM1301 download doesn't contain any useable electrical diagrams. Means I can't trace the circuit from gun trigger to CR1 Relay to Gas Solenoid Valve or anything else.

    This machine is fitted with a 200 amp Tweco gun and has what looks like factory installed Gas Solenoid Valve. Parts list in OM 1301N starting with serial JH292376 doesn't show a gas solenoid valve, and mine's a later/newer machine, so it shouldn't even have the gas solenoid that's installed? Should be a gas valve in gun only, right? Solenoid that's on valve is apparently a replacement made by Deltrol. Rubber looks good.

    Triggering gun I first get a 'psssh' of gas at gun but can't tell if the valve's solenoid is also holding open while welding?

    Miller parts site shows 6 possible gas solenoids listed, some 24V like mine, but none for Model 35.

    Ideas?? Thanks!

  • #2
    I got this little tip from this forum today. Hold a small ziplock or sandwhich bag tight around the nozzle and see if it fills up when the trigger is pushed. Maybe unhook the drive roll so it doesn't push the wire out too...Bob
    Bob Wright


    • #3
      You've got a bottle, gas hose to the gas solinoid then a gas hose out to the gun. Pretty easy to trace there without a diagram.

      I'd guess your problem to be within the gun casing itself. If you ever yarded the machine around with the gun, you've pulled the internal gas hose out of the guns harness.

      Looks like the early 35's had some sort of gas hose pinching device in the torch handle as apposed to a gas solinoid. they were supplied with a regulator but no solinoid
      Last edited by cruizer; 06-15-2011, 07:48 PM.


      • #4
        Thanks, AAMetalMaster! That's so stupid simple & logical it almost makes me tired hah! Too easy, THANKS!

        No, Cruizer, never dragged the machine around by the gun lead hose. I've babied it.

        "You've got a bottle, gas hose to the gas solinoid then a gas hose out to the gun. Pretty easy to trace there without a diagram."

        Yes, the plumbing is very simple, but plumbing isn't electrical schematics. I tried to discover what the actual control circuits are but Miller doesn't give that in the downloadable manual, maybe in house only. No real schematic diagrams there other than crude point-to-point component line diagram.

        This gas solenoid valve looks like original factory installation, and early machines supposedly had just that. These later ones are supposed to be controlled by the gun trigger valve, not machine's gas solenoid.

        As mentioned, it has a Tweco gun. Earlier machines needed a gas valve kit to be fitted in order to run a Tweco from what I understand, later machines were already set up for a gun mounted valve by Miller. Don't know why this machine even has the solenoid valve.



        • #5
          Mines an '83, looks like yours is newer. Mine has a factory gas solenoid inside the machine. Looking at the 1301Q owners manual from 1991, it shows a solenoid as well in the same place right above the fan.

          I tried changing the letter in the owners manual address. Seems mine is 1301k. It has a gas valve part number listed in the manual.


          • #6
            Miller gives the schematic to us techs, as for the early 35's with the funky gas delivery systems, I ment the early 1970's, yours would always have been a solioid


            • #7
              While back there was someone who was having about the same problem you are and the regulator was bad. Have you tried a different regulator? Checked the lines for leaks? Thats where I would start.

              Dont force it, use a BIGGER hammer.

              Linde VI-252C and Linde wire feeder.
              Hobart Cyberwave 300c.
              HH 140.
              Miller Big 40.
              Lincoln SAE 200J.
              Hobart GR-303.
              Lincoln tombstone welder.
              TD Cutmaster 52.
              Hobart Stickmate.
              Miller 211 w/ Spoolgun.
              Lincoln SA 200.


              • #8
                Thanks for all the information & help, guys, much appreciated here!

                Well I got brave and tore into it yesterday. First I pulled the gun lead and I needed to look no further! Where it clamped into wire feed drive the o-ring was split in two! So I checked the Tweco parts list, and hey, wait a minute!?! How come Tweco shows 2 o-rings there, one on each side of gas diffuser machining??

                So all this time I've owned it & used it the thing was missing an o-ring! That, and the one that was there was split. Now I know why it was such a gas guzzler too. NAPA autoparts just happened to have 2 of the correct size. Now it's blowing gas like sitting in the bathtub eating bean burritos!

                Thanks again y'all, one way or another we got it fixed!


                • #9
                  new be.. needs help

                  gentlemen and ladys, I'm new to this big gun stuff. I tried one and love it compared to my 110 buss box. Here's my story.
                  I was offered a miller matic 35, I heard the motor run, and heard the wire feed turning. It was missing the nut or cone to hold the wire on the long bolt
                  What do I really have to look for in a used machine(body shop) and how do i know if it welds. Has gas but not hooked up. Should I just run a length of wire through the feed and what voltage would be the best to try it on.low high??Dont know what year it is,
                  If it works, what kind of $$$$ would you think a guy should consider paying
                  If its not to much bother could you reply on my e-mail

                  [email protected]