THEy leak, they leak, and umm they leak.(read review)
I bought two pure energy tanks with these valves on them. let me say at first, they worked very well. then i suddenly found out that they are the worst valves ever. i don't know how people are rating these valves so high, but they are junk. COMPLETE GARBAGE. and if you think i know nothing about paintball, your completely wrong. heres whats the problem with them.
after i get them filled(by paintbal stores, and ace hardware)they leak. whereever your turn the valve knob, it leaks. This is because the seals onn the knob are complete junk.
I emptied the tanks and took the little snap rings off. i took out the knobs. There are two 0-rings on the knob. I went to the hardware store. i put good quality o-rings and perfect sized ones on the sports. i put the knobs back in. they guy filled thgem a little. guess what, they still leaked. so i took apart again. we put teflont tape where the o-rings were to creat a thicker and better seal. guess what, it still leaked. I even had my proshop put new o-rings on it, and it still leaked. i have no problems with my pin valve tanks. by the way, pin valve tanks only blow o-rings by misuse. you turn the tank a little bit, and then fire the excess co2. there you go, no o-rings blown after uising a pin valve co2 tank.
STAY away fro these valve. they are such garbage. i dont know if i got faulty ones, but i have 2(two)(dos) and they are jacked up. and i already explained that i know what im talking about. so these are crap. go with the pin valves. cheaper and will not leak
Don not buy these valves. They were very dissapointing to me. I would not reccomend these, but i do suggest pin valves
I have been involved in paintball since 1990, and in my experience, on/off valves are way more reliable than pin valves. I have never seen a on/off valve jam open, but have seen it any number of times with pin valves. Also, if the pin seal on a pin valve fails, you have to strip down the whole valve. Seal replacement on most on/off valves just requires the removal of the tap retainer and the tap (or the circlip in the case of the Smart Parts valve).
Having said that, most of my on/off valves (those that I own now and have owned in the past) have had multi turn taps, not the quarter turn taps that Smart Parts use. However, I do have one SP valve, that I have owned since these valves were introduced, and it hasn't given me any problems at all. I do not know why both of yours leaked when you got them, but would suggest that the reason they have continued to leak is due to using non-SP o-rings. SP tend to use o-rings with very specific sizes and durometers (hardness), not ones that are commonly available in hardware stores.
See if you can get some spare ones from SP. The right o-rings might fix the problem. If they still leak, I would try to get your money back, as it would suggest that they haven't been made to the right tolerances to seal properly. They should seal, and seal well.
i know why yours leaked. the small o ring that is where the air comes out of the tank when you take out the pin that you twist has a nick in it. just get a new one and clean out the valve area and make shure there is no rough or sharp edges where the air goes through. read my review.