Leaky QEV...need assistance

[achs_xc]

I have built my first copper air cannon using a McMasters right angle QEV. My problem is that when I fill the cannon with air I hear a leak coming from the barrel. Any suggestions?

[POLAND_SPUD]

just clarify this.... you hear a leak comming from the barrel after filling or while filling ?

if you here it after then you have a 99% chance it's caused by a leak on pilot side

if you here it while filling then you either have a leak, you have connected to the wrong ports or there is something wrong with the valve itself ( but I've never heard of even one fu**** ** qev

[daberno123]

Are you filling from the chamber or the pilot side?

If its the chamber than there's your problem.

[Ragnarok]

As has already been said, two common issues with QEVs are that they've been connected the wrong way around - exhaust to pilot and vice versa - or that they're being filled from the chamber when they need to be filled from the pilot side.

Alternatively, if neither of those is the case, it's entirely possible that your QEV has debris on the sealing face, which may require you to take it apart to fix it.

However, 9 times out of 10, it's one of the first two problems.

As a final note, pictures are always very useful when we're being asked to diagnose a problem - you get a faster and more accurate result.

[Daltonultra]

Try pouring a little water across all your joints while it's pressurized. Any leaks will shows as bubbles. As said above, 90% chance you have a leak somewhere on the pilot side.