New regulator/flowmeter leaking

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Hi All,So I picked up my new welder and all of the associated TIG gear earlier this week.  Set it all up and checked everything out according to the manuals - I hate manuals, even decent ones .  So when I'm checking out the regulator I notice that its leaking gas pretty quickly, drops from about 2200psi to about 1000 in about 30sec when I pressurize it and then turn off the cylinder to watch for leaking.  Checked everything out again, made sure the threads to the tank was clean and that everything on was tight etc and still leaking even with just the regulator and tank.  It was a brand new unit and I needed a longer hose anyways, so I went back to the LWS to have them check it out/exchange it.  They put it on a tank, sprayed leak detecting fluid on it and of course no leak.  They walked me through what I had done and I had followed all of the right steps - but, it turned out what I thought was tight was not tight enough.  New regulator meant the brass on the seal still had some machine marks. The LWS used a big *** wrench and really leaned on it, tighter and loosened it several times until the seat was smooth and shiny.  Took it home, put it on and lo and behold no leaking at all even after an hour.I'm just posting this in case another newbie has a similar problem some day - I learned a couple lessons.1) Using a LWS is awesome.  Having someone accessible that can actually show you what you need to do is great, even just being there a couple of the guys ending up giving me all kinds of tips / advise on what to practice, what to watch out for etc.2) You can really tighten down the fittings - I mean almost hang off the tank while holding the wrench.  Normal crescent wrench tightening may not be enough for a new regulator, they suggested picking up a 1 1/8 open end wrench and really leaning on it anytime I had a new regulator for at least the first half dozen times.  They said once it had a good seat that I wouldn't need to tighten it as hard, but that it would hurt anything if I did.Scott
Reply:Glad to see they got you taken care of. However keep something in mind for the future.I'm not the biggest fan of the idea if it leaks, lean on a bigger wrench. What happens many times is guys distort or damage the valves themselves when they do things like this. Or if the valve itself is damaged in some way, you'll do the exact same thing they just did, only now instead of getting the stem nice and smooth so it fits well, you'll swage a big gouge into your stem and it won't seal well on other cylinders in the future.I usually tell guys to snug down the regs nice and solid, but not to really lean on the wrenches. If the reg isn't sealing well, 1st thing to do is take it off and look at the valve seat and see if there is visible damage. If so, call your supplier and let them know the cylinder you just picked up is damaged and that you need to bring it back in for a replacement. Some places will work with you and tell you to bring it back the next day possibly and just use it the best you can if you can't make it back right away. Some others will want you to bring it back as is and may hassle you if you use it and it's obviously way down, even if it's due to a damaged valve. Best to know in advance how they want to deal with it.If you don't see any damage, wipe down the valve seat and stem surfaces with a clean lint free rag. This is especially important with O2 where contaminants can cause fires. Then make sure you don't cross thread the valve when reinstalling the reg and snug it up again and see if it seals. If not give it a little harder tug on the wrench and see if that helps. Problem may be that some guy in the past followed the instructions you got and went Magilla Gorilla on it with a cheater bar and has distorted the valve seat. It's up to you to decide if you can keep trying to snug it up and see if it seals, or when enough is enough and you want to stop before you distort your stem. I usually feel if I find I need a bigger wrench than I usually use, or if I need more than one hand on that wrench, I'm getting too close to the point where I'll do damage to the reg stem and either live with it, or call the LWS and take it back.Stems are often locktited into the regs so they don't back out. In many cases you'll snap the brass before the locktite will give. Remedy is heat to loosen up the locktite, but with a lot of soft brass and seals in a reg, you need to use a lot of caution so you don't heat up parts you don't want to, or anneal the brass to the point it's butter soft and almost impossible to remove. Distorted or damaged stems can be a real PITA at times.Last thing, remember flow gauges always allow flow when open. So a "leak" may not be at the reg if you notice things bleed down. It could be a leaky solenoid in the machine, a bad fitting connection down line or possibly a damaged hose some where. My mig will very slowly bleed down when the cylinder is off if the reg is sealed well to the cylinder. I'm talking about the gauge dropping in 2 or 3 days. The reg on my tig on the other hand will hold pressure for weeks, and I'm constantly double checking it to make sure I didn't leave the reg on by accident. If I notice the pressure drops a lot faster, then I double check the reg is tight and watch to see if there's signs something has gotten damaged elsewhere in the system..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Don't get too excited about your little leak and cause you to perhaps damage your regulator's male 510 fitting by over tightening it.......most will leak down once gas bottle valve is shut tite.Do a soap bubble test and determine just how bad it is....If when bottle gas valve is open you have a major leak, then yeah, you need to snug it up to save gas.....But if instead it leaks down after several minutes, you will never in your life notice a savings over many years....If you stop welding for lunch, shut your bottle valves tight and back off the regulator t handle.Never expect your welding machine solenoid valves to be bubble tight because they are only intended to be gas flow control valves and not shut off valves....same for your regulators and hoses....They should be assembled and fit to where they don't leak lots either externally or thru, but never expect ythem to offer full bubble tight isolation.ALWAYS exercise good engineering practice and shut your bottle valves tight and back off your regulators fully, plus open and vent your gas cutting hoses thru torch head valves and leave them open until next time you cut where you shut them first then open bottle valves and finally adjust t handles....The bottom line is if or not your gas bottle valves hold bubble tight...totally bubble tight. If not,  place your flammable gas bottles outside in the breeze overnight and fuss at your LWS next time you swap bottles.Last edited by pigeonpoop; 01-11-2014 at 05:54 PM.
Reply:I keep a small spray bottle of dish washing soap mix in my shop. When I change a cylinder or any portion of the gas lines, I will tighten the fitting as I think best. A couple of shots of soap mix will immediately show any leaks and you can tighten up a bit more. If it still doesn't stop, you have to disassemble the joint and examine the fittings. Works for me.Miller Millermatic 252Miller Syncrowave 200Liincoln AC-DC 225Victor O-A Set