Valve not keeping Presure

[APINTA]

Hi I hope that someone can help me on here please I have a strange problem with a PB I have and tried everything that I can think of. This what happened I had a beer in it but it would not keep its pressure so what I did was transfer the beer to bottles and then foot pumped air into the PB but as soon as it got to 5 psi I heard a loud whistle coming from the valve which normally means you have gone over the recommended pressure but that normally happens at over 12 psi but this was happening at 5 psi . So I put the PB into a bath of water to check for leaks and then I found it a leak coming from the the little escape hole on the valve with bubbles that a scuba diver would be happy to see!. So I thought it needs new escape rubber which I put on tried it again still air coming out so i changed the complete unit as I have 5 spares each one gave the same result . Should I change all the rubbers and seals I have even changed the lid same result. PLEASE can anybody help me here. Thanks

 

[Alside101]

Put a tie wrap around the pr band but be warned that if you go over by a lot you will pop your pb

 

[APINTA]

Will give that a try and let you know

 

[APINTA]

Well I tried but once i put the cable tie on it would not go though the hole in the cap tried it on the small valve rubber but that did not stop iteither

Put a tie wrap around the pr band but be warned that if you go over by a lot you will pop your pb

 

[APINTA]

why would it do this my other PB barrels are fine and both have the same caps and valuves