Cracked Power Tube???

[68magLAPCObarrel]

This is my first post, I have read thru all of the air leaking threads, but I do not see anything that helps my issue. First off I am running a 68 classic with Air America Raptor system, benchmark 45 grip frame, LX bolt, LAPCO barrel, everything else is stock. The mag as been working fine, I have played with it for months with no problems. Here is my issue, one day I hear a very slow leak coming from the gun when it is gassed up but I could not find where it was coming from. The gun worked fine, but after a few weeks the leak got worse. I then was able to find the leak coming from the grip frame and between the body rail and body, not out of the back of the gun and not down the barrel. When I hold down the trigger the leak will stop, so that is showing that the On/Off Assembly is where it is leaking from. I bought a parts kit and installed all the O-rings for the On/Off Assembly and in the AIR Valve but did not seem to fix it. I have used my on/off assembly in another mag and there is no leak. The leak is very bad, will drain a 3000 PSI bottle in one game. From what I have read in the forums it looks like I may have a cracked power tube. Is there a good way to see if there is a crack in the power tube? And where would it most likely be? Just want to be sure before I send it in, I only have one star left for service. If there is anything that I am missing let me know.

Thank you,
68magLAPCObarrel

[rikkter]

if you hold the trigger and the leak stops, its NOT the on off assembly. its the powertube area thats the problem. check all the orings, even the oring on the brass tip. it may be leaking from there.

[PyRo]

Your level 10 may be giving you a problem, do the shims/carrier thing for a barrel leak.

[dyeforever]

how offen does a power tube crack? can u replace it with out buying a whole new valve?

[xen_100]

1 out of 10,000 will have a powertube crack. that is not likely your problem.

as others have said. if the leak stops when you pull and hold the trigger, then on/off top is doing exactly what it is supposed to do. more than likely you have a problem with the o-ring that seals the powertube to the valve, or the o-ring that seals the on/off bottom. (if it is not leaking down the barrel it is not an LX problem.) if you already replaced the on/off bottom o-ring (the one that seals the bottom part of the on/off from the outside world) then I would suggest you need to send it in to have the poewrtube checks for a bad o-ring. (this is not a user serviceable part)

[PyRo]

I don't think there are any o-rings in the PT that you cannot get to. The PT should be loctited on, or is welded, You shouldn't get leaks from there unless you have a really old mag and it is unscrewing. I would just check the o-ring, and change your carrior or add/remove shims whatever your supposed to do for a level 10 barrel leak.

[xen_100]

it is loctited in place........and it does unscrew.. there is an o-ring in the powertube side that maybe leaking.

if it is not leaking down the barrel (or out of the bolt) then it is not an LX issue.

[68magLAPCObarrel]

Well there is no air coming out of the barrel, when holding the gun the air is coming thru the grip and hitting my trigger finger, and coming from the sides of the body rail where the valve assembly and body meet. When holding the trigger in there is no leak at all, when the trigger is released then it leaks. I have replaced the bottom o-ring on the on\off bottom 4 times and the leak does not change. I state again that I have used my on\off assembly in another mag and it does not leak at all. Could this be an out-of-round issue with the hole where the on\off goes?

Any other ideas?

Thx

[xen_100]

it is posible......it would have to be pretty well warped though.

either way, I think a trip to AGD is in order. if the on/off hole is not right, that is only something AGD can fix (or replace). If the powertube o-ring (the one that seas to the valve body) is leaking, then again, only something AGD can fix.