Vintage Double Hose

Took my trusty Mistral for a dive yesterday to test my rebuilt J valve. I started with approx. 1700 psi. I noticed as pressure dropped, even before the J valve closed, a constant air flow that could only be stopped when going into a head down position. I'm not talking about a huge free flow, just a steady air flow strong enough to bypass mouth piece valve and DBE. It does not seem to happen at higher pressures. Maybe spring getting weak? I did replace seat and spring when I rebuilt reg a couple of years ago and it has a handful of dives since.

There are a few things that can cause this:

-weak HP seat spring
-Seat has been sanded too many times (deprecated due to Bryan making seats)
-Using a new, thin first stage filter without a washer (I've done this)
-Levers set too high


Work your way through those and keep us posted on what you find The two most common, in my opinion, are the lever height and using a thin filter with no washer.