View Full Version : Question on a Miller Mig 135 weldor

Your Old Dog
12-04-2005, 09:57 AM
I know I could join a welding forum and ask this question but thought most you might also know the answer.

My Miller Mig 135 looses gas when I'm not welding. So I have to remember to turn of the bottle each time I use it. If I don't, I'm out $15.00. Is this normal or is there a problem with my unit?

12-04-2005, 10:11 AM
You have a leak somewhere. Squirt some soapy water on all those external connections. There should be no flow except when you pull the trigger. To leak test finally, leave overnight with the cyl valve shut, you should only see a small pressure drop on your low side gauge.

I just bought one of those in Sept.......how do you like yours?

12-04-2005, 10:13 AM
I've always thought it a good idea to turn it off after each use. and I also back off the regulator.

I use the same "habit" when I use my propane/oxy setup.


12-04-2005, 10:24 AM
Thanks for the tip about the leak check. It's surprising how the obvious will escape us at times. Guess that's part of getting old. Have the same problem with my Hobart. Passed it off as cheap internal construction.

Yes I do try to shut everything down when finished, some times old mind forgets.


Your Old Dog
12-04-2005, 11:05 AM
Thanks Chester. I always close all tanks down when I quit for the night, if I remember I was using it.

The reason I asked is because when I do the test you suggest it bleeds off within an hour or two when I want to use it again.

I wasn't sure if maybe a cheaper welder like this didn't have an automatic valve somewhere to take care of that.

3 Phase Lightbulb
12-04-2005, 11:20 AM
My TIG and MIG welders will bleed off the pressure in 30 mins (maybe longer) after I close off the valve. I don't think the valve(s) inside of the units are designed to hold pressure indefinitely. I always close the valves when I'm done.


12-04-2005, 11:23 AM
I have the 175 which is that machines bigger brother, mine holds pressure good which is a good thing because I forgot and left the bottle on for about 3 weeks and there was not a noticable drop in tank pressure
I love mine but A side note if you decide to get the spool gun for it so you can weld Alum, the gun and controller cost more than the welder its self though it does seam to work good on Alum (I need lots more practice)