Vintage Double Hose

I recently purchased a NOS Scubapro Balanced Adjustable 156 second stage. It breathes fine, but the purge is not operating properly. When the purge is fully depressed, the regulator "locks" into a very strong free flow until the mouthpiece is covered and the internal pressure equalizes. I have another Balanced Adjustable whose purge functions normally - push it in and you get a moderate flow until the purge is released and the flow stops. The newly acquired B/A has a way too forceful flow. Intermediate pressure off the Apeks first stage is 135psi.

Any idea what could be causing this purge problem?

I don't have a Scubapro dealer anywhere nearby and am about to send it off somewhere - does anyone know of a really good Scubapro repair facility? I'm located Davenport, Iowa.

Thanks,
Steve

The better or finely tuned Scubapro 109 will behave like that. I try to tuned them so that they are that sensitive.

If you need to de-tune to use it as an octo, just turn in the diver adjustable knob.

Thanks Luis.
This new B/A has a plastic ring installed on the adjustment knob shaft that limits the de-tuning of the reg. My older B/A doesn't have this ring. The plastic ring is split on one side and at first I thought it was some kind of shipping "restraint", but I wasn't sure, so have left it on. Have you ever seen this plastic split-ring before?

Ok, I removed the plastic split-ring (which was a son-of-a -gun to get off), and now I can de-tune enough to get rid of the purge free flow.

Thanks again Luis.

I find that the lever height will do this. Adjust the orifice a hair.

This plastic ring was introduced to get better work of breathing (needed for certification). WOB would be too high if fully turned in....