ToolSteel Posted March 17, 2012 Share Posted March 17, 2012 I've just started using oxy-acetylene to cut and weld. Last night the strangest thing happened. I was just getting started and was setting the oxygen pressure when I noticed that no matter how tightly I closed the valve, the oxygen kept flowing. Here's my set-up: I have a Harris 2000 Model 85 body and a Harris 2100 cutting assembly. I use a W2030 mixer and have installed a pair of flashback arresters. When I attach the cutting assembly, I normally leave the bottom oxygen valve wide open and use the oxy valve by the upper lever to control how much oxygen I use. When I set it up this way, it seems to work OK since I'm essentially bypassing the lower oxygen valve. I should also mention that I can completely unscrew and remove the lower oxygen valve. The fuel valve won't budge. I'm not foolish enough to use the rig until it's fixed or someone tells me what I'm doing wrong. Thanks Quote Link to comment Share on other sites More sharing options...
Old N Rusty Posted March 18, 2012 Share Posted March 18, 2012 Leaks? was the cutting lever depressed ? I use Victor equipment and it is the same , If you have a long hose it will take a while to get full pressure and hiss a while at the regulator. Make some sudsy water and leak test all possible places that could leak . From what you posted I cannot say you doing anything wrong . Be Safe! Quote Link to comment Share on other sites More sharing options...
Frosty Posted March 18, 2012 Share Posted March 18, 2012 You've answered your own question. Turning it off as hard as you can is just what lots of people do and ruin the valves. Torch valves are precision devices and seal positively with a light fingertip turn, cranking them hard damages the seats and that's all she wrote. If the local welding supply won't repair Harris you may have to send it to the manufacturer. Harris aren't rare or exotic torches though, so the welding supply will "probably" repair it or tell you who will. Think of a torch like it's a fine watch with the one exception being a malfunctioning watch isn't likely to blow you into the next county. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
ToolSteel Posted March 18, 2012 Author Share Posted March 18, 2012 Thanks for the replies. There are no leaks in any of the connections. I always check with soapy water. The oxygen is shooting right out of the welding tip. Closing it down too hard? I never would have thought of that but I've never been told not to. I have to admit I torque it quite a bit. I'll take it to a nearby Airgas and see if they can help. Thanks a lot guys. ToolSteel Quote Link to comment Share on other sites More sharing options...
John McPherson Posted March 18, 2012 Share Posted March 18, 2012 You may have just backed the valve out of the threaded tube (90/45 degrees) off of the torch body, there should be a hex nut compression fitting under the mushroom cap of the valve. You did say that valve came out completely, better the oxygen than the fuel! Any packing washers may have come loose at the same time. Number one student problem: putting the gorilla grip on a soft Tobin Bronze fitting, and wrecking it. I have sent a dozen handles out for repairs from our school, and boxes of regulators. Cutting head diagram found online: http://www.atlweldingsupply.com/Harris-71-3-72-3-73-3_c_906-1.html Quote Link to comment Share on other sites More sharing options...
ToolSteel Posted March 18, 2012 Author Share Posted March 18, 2012 John, I'm not sure I understand, but the cutting torch is in perfect condition. The lever and the oxygen valve work the way they should. It's the oxygen valve at the base of the torch... the one next to the fuel valve... that's giving me problems. In any case, I'll need to have it repaired. Quote Link to comment Share on other sites More sharing options...
John McPherson Posted March 21, 2012 Share Posted March 21, 2012 Sorry, I was clear as mud. You said that you could unscrew the Oxygen adjusting valve completely out of the torch handle, but not the fuel valve. You may have lost or dislodged some of the vital bits when it came out. DIY repair kits are available. I believe that in this model, the valves are standardized and interchangeable to fit torch body or cutting head.You could take the other oxygen valve in the cutting head apart to compare. IIRC, they are a screw in a tube that is threaded both internally and externally. The needle valve runs up and down the internal threads to control gas flow. The outside thread uses a compression nut to attach the needle valve assembly to the torch body, and limit the travel. If that compression nut is loose, the whole valve will fall out, rather than stop. Quote Link to comment Share on other sites More sharing options...
ToolSteel Posted March 21, 2012 Author Share Posted March 21, 2012 John, You know a lot more about this that I do. When I dropped the torch off at Airgas yesterday, I noticed that the hex nut beneath the oxygen valve was still attached when I unscrewed and removed the assembly. I checked the hex nut on the fuel valve and it was stationary as the valve was opened and closed. Obviously, the oxygen hex nut came loose. I briefly thought about taking the torch back home and fiddling with it, but then I thought about blowing my head off if I were wrong. I had the torch sent to Harris to be fixed. I thank you and everyone else on this forum for your replies. P.S. I don't think anything fell out when the valve was unscrewed because prior to yesterday, I only did that once, and I was paying very close attention to what I was doing. ToolSteel Quote Link to comment Share on other sites More sharing options...
pkrankow Posted March 21, 2012 Share Posted March 21, 2012 When you collect you torch take the opportunity to ask questions so you know what to do if this happens again, or anything else you have come up with before. Phil Quote Link to comment Share on other sites More sharing options...
macbruce Posted March 21, 2012 Share Posted March 21, 2012 I had the same problem with a victor only with the fuel. I fixed it by backing out the lock collar/nut then seating the valve firmly, then I lightly tapped with a small hammer the top of the stem/knob. This seats the ball bearing into the brass seat. Then Re tighten the lock nut to the desired resistance and try it.....It should leak less or stop. If it still leaks (keep a bowl of water handy)I repeat the process...... Quote Link to comment Share on other sites More sharing options...
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