millermatic 135 not ejecting gas anymore.. help!!

[paulg1080]

Hi, sorry for the long post here...

OK, I was using my millermatic 135 today. I broke it out for a project I'm doing. It was sitting for about 6 months. 3 months in the back of my pickup (in the cab) and 3 months in the basement.

Anyway, I started welding and had some trouble with a lot of popping.. I realized it was my breaker, and swapped it out... So now I was getting a good powerful weld.. nice.. HOWEVER, now I was having trouble with the bead.. looked like I wasn't getting any gas. So I checked my tank and it was full open, and the tank was full. I thought maybe my metal had some paint residue that was causing the problem, so cleaned the surface real good with my angle grinder and laid another bead. Same thing!!

So I went to my tank and there is a separate flow valve that controls the flow... You know, its a philips head screw with a nut situated right between the gagues.. I loosened the nut and turned the screw to the right.. a bit too much actually as I turned it all the way it could go.. and I heard a loud hissing noise.. so I backed it off until I couldn't hear the gas come out any more.

I thought at this point I should have enough gas (CO2/Argon) to get a good bead.. I tried again, and same thing... looked like no gas was coming out. So now I notice my LPM gague is at ZERO, but my PSI is at something like 1500.

So, I disconnected the valve from my bottle and reattached. The gagues went back to normal.. phew!

I picked up the gun, pulled the trigger, heard a loud poping noise from the nozzle, then, no gas.

No matter what I do, I can't get the Argon/CO2 to come out of my nozzle. I actually pulled the clear tube from the fitting that feeds the gas into the welding cable/gun assembly to see if anything is coming out, and nothing. I put my finger over it and pulled the trigger.. nothing... so I think I can safetly say its not a clogged nozzle... even though I took the nozzle off and tried as well.

Any help is greatly appreciated. I have this project that must get done ASAP.

Thank you all.
Paul

[Black Wolf]

Let's see if we can get you up & running. I am not super familiar with your particular welder, but we can get you through this. Disconnect your drive rolls while diagnosing.

Step 1: Establish that you have gas flow to the back of the wire feeder by loosening (not removing) the fitting that is attached to the gas line from your flowmeter. If you have a steady flow of shielding gas that doesn't sound to be losing flow, re-tighten and move on to step 2. If you do not have gas flow, go back to your flowmeter and adjust the settings until gas flow is heard at the back of the wire feeder. Jump ahead to Step 6

Step 2: Establish if you have gas flow at front of wire feeder and into back end of mig gun by disconnecting gas line joining wire feeder to gun and pressing trigger. It sounds like you have already done this.

If you have gas flow at rear of wire feeder, and no flow at the front of the wire feeder, your problem is internal. Either the gas soenoid is not operating properly, or you have a blockage from a foreign object.

Step 3: Listen closely at wire feeder while you press & release the trigger, you should hear a slight clicking sound as the gas solenoid opens & closes. If there is no sound, concentrate on checking wiring to solenoid and fuses (with machine unplugged) If you have sound, you have a blockage.

Step 4: Turn off you bottle of shielding gas and remove gas line fitting from rear of wire feeder. Some wire feeders have a filter or a flow orifice inline with the gas flow. Check for these and their condition. Blow through them in the opposite direction of gas flow to ensure clear passageway. If everything looks good, disconnect the gas line at the front of the wire feeder where it connects to the gun. Using low pressure compressed air, or VERY CAREFUL short bursts, hold the trigger open to energize the solenoid, and introduce the compressed air into the front of the wire feeder and push obstruction out the rear of the feeder. Trust me you'll hear it.

Step 5: Re-attach the gas line fittings, turn on the bottle, and re-test at the front of the wire feeder. You should now have gas flow at the front if the blockage has been removed.

Step 6: Re-attach front gas line between mig gun and wire feeder. Listen at gas diffuser for gas flow.

If everything checks out, you're up & running again. Engage your drive rolls and get back to your project.

Best of luck.

Later,

[dabar39]

paulg1080, sounds to me like a bad or sticky gas flow solenoid. If the machine has been sitting for a while especially in the heat and humidity of a locked vehicle, that's where I would check.
Follow Black Wolf's directions and you should be able to figure it out pretty easy and get back to welding. Dave