A-5 won't stay gassed

[Turtle-Prophet of Doom]

Yes, even the venerable Turtle needs help. I have been beating my head against the wall for 2 hours now and have finally thrown in the towel and decided to ask for help. I can't get the FRC to keep a gas charge. I know there is gas, plenty of pressure from the tank to the reg and gas is getting to the valve. Pull the trigger and I get the out of gas burp... we all know the sound. It's not the reg because I can bypass it and get the same result. I have all new o-rings and they appear to be fine, I have a new valve plunger as well and it also seems to be in working order. My madman springs are all shot so I'm back to using the stock spring but that should not be an issue. I've just run out of ideas... It's probably something so simple that I'm going to kill myself....

:help:

[ricebrnr]

ONE BURP? or the run down fart?

if its one burp, as in cock fire no recock, check the detent. It may be in backwards.

[deluxestogie]

I would suggest tearing down the entire marker and then just reassembling it. You'll discover what is out of place. It sounds like the sear is not catching the rear bolt:

• inadequate pressure - ruled out
  
• bad orings - ruled out
  
• bum main spring (usually if it's too strong or out of position)
  
• missing spring guide pin
  
• foreign body in receiver slide area or inside valve
  
• cracked power tube
  

One trick in software programming is called "confessional debugging". You can reassemble the marker while explaining how to do it to someone else (even a complete novice). In the process, you will discover the error on your own. Explaining puts your brain into a different perspective.

[Turtle-Prophet of Doom]

ok, here is a list of things I think I have ruled out.

Air Supply: I have used 2 different 24oz CO2 tanks with the same result using a remote(with and with out stab), using the bottom line(with and without stab) and straight into the T-stone.

Remote: Since I have and the same result without the remote I think that's not the problem.

Palmer's: Again, same result both using and not using it.

I'll take the internals out and rebuild them again this morning so I can eliminate that(or confirm it), the ball dentent is facing the proper direction and I did remember to put the springs back in along with the guide rod.

UPDATE: I have determined it is not the valve itself. I have secured another A-5 as a test platform. I have swapped the old valve with teh new one in the stock power tube and the valve works fine. I placed the new valve in the DOP power tube and got the same faliure as before. So, now my question is this: The DOP power tube is a tight fit in both markers, could this be the problem? If so would loosening the bolts resolve this problem?

[deluxestogie]

Are you saying that this problem arose only after adding the DOP power tube, and did not exist prior to that? If the DOP power tube fails in both markers, but the stock power tube with the same valve works correctly in both markers, then it sounds like a manufacturing variation in the DOP power tube. You might want to just call DOP and get a replacement.

PS: Everybody seems to be afraid to give you bad advice. I'm perfectly comfortable giving you bad advice.

[pk]

I believe the fit of the powertube is supposed to be tight (mine is anyways), air is not supposed to travel on the outside of the powertube, only the inside. If the powertube is not cracked, it could just be too loose around the tombstone or valve body, but it seems like you would hear it leaking someplace if that were true. I'd agree that eitherway it sounds like it needs replacing.

I was going to say cracked powertube before, but deluxestogie pretty much nailed everything above (and then some). If you say your pressure is fine & air is getting to the valve and your not hearing any leaks, it has to be either the powertube, sear/bolt wear, or something like a missing valve spring.

Edit:
Although it is possible that it was over tightened, it shouldn't do it again when you re-assembled the marker unless you cracked the powertube. Usually over tightening would either lower your fps barely or cause your gun to not recock (not enough oil). I never really considered over tightening causing the powertube to crack, but when dealing with aftermarket products anything is possible and like you said it's a tight fit as is (though I thought the DOP powertube was made of aluminum?).

I was worried that I might have overtightened my gun the last time I tried taking it apart. Now, as soon as the screws give some resistance, I stop at straight up/down/left/right or the next 45 degrees imbetween (either + or x). And although hex would actually be every 60 degrees, it has definately helped me out in determine a good amount of resistance with no worries at all.

[Turtle-Prophet of Doom]

deluxestogie said:

Are you saying that this problem arose only after adding the DOP power tube, and did not exist prior to that? If the DOP power tube fails in both markers, but the stock power tube with the same valve works correctly in both markers, then it sounds like a manufacturing variation in the DOP power tube. You might want to just call DOP and get a replacement.

PS: Everybody seems to be afraid to give you bad advice. I'm perfectly comfortable giving you bad advice.

The thing is that the DOP tube has been in the marker and working for a year and a half. I just don't understand why the tube would cause the problem when it worked fine in January when I played last.

Thanks for all the advice guys!