Minor free flow when tilting head downward

[ScubaSarus]

On my last dive my Blizzard Reg started to free flow every time I turned my head downward meaning my mouth piece was upward. If I took the reg out of my mouth and tilted it upward there was a full free flow. If I kept it in my mouth it was pretty much OK except a slight air discharge constantly comming out when I faced down.


I had the reg loosed for summer diving and wonder if all it needs is tighening up.

I believe its obvious its a second stage issue.

 

[DA Aquamaster]

This is due to case fault geometry where the center of the diaphragm is lower than the top of the exhaust valve. It is a normal condition that often dictates the lowest useable cracking effort for a regulator.

Face down represents the worst case situation where the difference in height and pressure between the diaphragm and exhaust valve is greatest. What happens is that air slips out the exhaust valve to equalize the pressure and the diapgragm rises. If the cracking effort is too low, the poppet will open before the pressur eis equalized and a slight freeflow will result.

In your case, the low pressure seat has developed a seating groove over time that has in effect reduced the cracking effort of the second stage. The quick fix is to adjust the second stage slightly to increase the cracking effort. If it was serviced recently, it is a case of the tech not anticipating this seating effect adequately and needing to just readjust it. If the reg has been in service a year or so, a better fix is to take it in for an annual service as this would be one of the symptoms indicating it is due for service.

 

[ScubaSarus]

Hey thanks. It was just serviced and most likely needs tweaking per your message. I'll look into it ASAP.