Sun Jan 16, 2011 9:46 pm
Jiguad,
Check for binding between the first stage seat and the bushing (the one with the o-ring in it). I have rebuilt quite a few of these regulators, and sometimes the tolerances are not that great. You may have to take a needle file or a locksmith's file and smooth the first stage seat shaft out a little bit. That whistle that you hear, probably on the inhale, is not supposed to be there. It is usually that seat shaft rubbing on that bushing when it moves to supply your second stage with more air via demand. Another way to narrow it down is to take the second stage off and put an air gun on the first stage. Key the air gun several times. If it still whistles, then you have narrowed down where the noise is coming from to the first stage. If not, then check your lever in your second stage for metal to metal contact. Also, you can check where the second stage diaphragm contacts the demand lever. Sometimes, on the old levers without teflon, they can whistle or squeak on demand. Putting a little oxygen compatible grease on the metal disc of your second stage diaphragm will cure that.
Cheers my friend,
Ron
The impossible missions are the only ones which succeed. -JYC