Pressure barrel leaking air

[Griffter99]

Hi,

I currently have a lager in my 2nd fermentation stage pressure barrel. I sampled a little bit earlier and it came out flat. I inserted a gas bulb into the top and immediately noticed a hissing sound at the top of the barrel.

Obviously there is air escaping, my question is whether or not I can remove the top and attempt to reseal it by applying more Vaseline etc? Will this ruin the beer or is it something that I can do?


Thanks