Paintball

[Steelrat]

Hi,

FOr some reason, my AT-85 has started leaking. When I air it up with an HP tank, all I hear is a hissing sound, and the gun will not cycle.

I have disassembled the reg, and oiled it up, and all the orings and parts look good. I can't feel any air coming out the end of the barrel, but there is definately a steady leak there.

Any ideas?

[RoBo]

valve seal possibly -

[Gumby]

You won't feel any air coming out the barrel unless you are firing it. The valve tube is open to the internals unless the hammer is striking it.

Take the guide plate off and make sure that the cog can move freely. Next back the regulator screw at least one full turn counter-clockwise. This will reduce/remove the pressure going to the pneumatics. If the valve is the source of the leak this will not effect it at all, if the source is something else the leak will decrease.

If I had to guess, I would say your piston shaft has lost the lower e-clip and is venting the regulated pressure. With the correct diagnose I can't really go into fixing the problem. First find out where the leak is actually coming from.

[Steelrat]

Okay, I adjusted the regulator screw, and the leak sound changed a bit. At one point, I could hear the gun "cock" and I was able to fire two rounds, then the gun made a "sproing" sound when I pulled the trigger and wouldn't do anything else, but no hissing sound. It sounded like the hammer released but nothing happened, and there was no firing or force to recock it. After taking the tank off and putting it back on again, it started hissing again, and when I messed with the reg screw again, it cocked again, but when I pulled the trigger, it made that "sproing" sound again, and nothing else would happen?

Ideas?

How much does ATS charge to take a look at it?

[Steelrat]

Now it gets even goofier. I rechecked the reg, set it flush with the scribe pointed in toward the barrel. Put on the tank, and the hissing started again, though the gun cocked. I fired a few rounds, and it was hissing loudly the whole time. Then, while firing actual paint, the gun fired, then started hissing even more loudly, with air seeming to come out the back of the gun pretty rapidly. I took the tank off, took out the mag, and looked inside, and there was a ball lodged partway in the barrel.

I'm guessing it should just go to ATS.

[Steelrat]

Anyone?

[snipeo101]

i had something like this happen to me (not as long but it did)

what was happening was that something was keeping it form cocking on the final stroke.

check your mag is is securely and push up very slightly. try re greasing the guide plate. then just work getting it to cock again.

I would suggest taking it apart and regreasing and oiling everything.

if that still doesn't work then you can always send it to gumby. he'll get it working.

i would try taking it apart carefully first though. even if you brake something its important to know how these guns work. and if you ever have problems later try pleasing it with a sacrifice, its always worked for me.

Good luck

[Gumby]

Sorry for not replying yesterday, my new iPod toy is great at viewing but typing out messages takes too long.

There could still be a couple of different causes for the problem you are having. A constant leak that does not prevent cycling normally indicated either a damaged spool seal or the main valve face seal. The problem is that now we're getting into the area where you need to find that leak and the easiest way to find it is not the safest way. Try this; take out the regulator cap screw, spring and piston out of the regulator cavity. Put the cap screw back in and make sure you leave the regulator sleeve in place (otherwise you'll blow tank pressure straight out the regulator cavity). Now connect your air again. There should be no pressure going to the pneumatics now so if you hear a leak still it can only be from the main valve seal. Now if you have an air leak from the regulator cavity then your poppet seal is damaged.

A very important step is to put that cap screw back in place. There can be a chance with older guns for the sleeve to fail and blow out of the housing, this is very bad and will cause severe injury including possible death. A few years ago I had one blow by my head bounce of the ceiling and break a jar 40 feet away on the other side of the shop. I kid you not, if you are not completely sure of what you are doing don't do it and just send it in.

The procedure I just went through will isolate the leak. This will not correct it, just confirm what is leaking. It may be simplest to send it in for the repair, but I can walk you through some more steps if you would rather go it alone.

If the poppet is leaking this will allow higher pressure than needed to get into the pneumatics and will cause it to leak.