New Poseidon Xtreme Regs

[Cheekymonkey]

So for christmas I ended up with four brand new Poseidon Xtreme regs. Last night I had the oppurtunity to hook them up to my new tanks and when the air was gently turned on they began to freeflow, each one of them. After taking one breath, the freeflowing would cease and the regs would function fine, until they were removed and repressurized again, at which point the cycle would start over.

Is this is a normal occurance with Poseidon Regs, I had heard before that they are shipped untuned and need to be tuned before use, but the shop that was reccomended to me said more often than not they ARE in fact shipped tuned correctly.

The place reccomended to me in Florida was Tampa Adventure Sports, and said they will do the tuning for $20 each stage so $160 total for my four regs. Is this reasonable as well?

 

[The Chad]

If they free-flow for a second when you turn them on, and then stop I'd say they are tuned. You'll know for sure when you get in the water and duck you head under to put on your mask and one free-flows til you tip it upside down. Sounds high to me....all you need is a small alen wrench and a pair of real small (roach clip) pliers as the adj you worry about is in the second stage

 

[Jimmer]

I haven't dove Xstreams, but I have owned Jetstreams, and I remember a Poseidon tech guy telling me once that you have to put your thumb in the mouthpiece when you turn them on to stop the freeflow, and that it was normal for them to do that. So I doubt you have anything to worry about, but it never hurts to have them checked out.

P.S. Four Xstreams?????? Damn that's a good Christmas gift!!!

 

[SwimJim]

I've had an Xstream for two years now. When you pressurize the reg you will hear a shot of air, like a freeflow. It will stop immeadiately. This is normal. Freaks the uninitiated out. You got four of them for Christmas? where do I go to get adopted? Seriously though, they are great regs. Careful with the purge though, it will clear your ears. I kid you not.

Jim

 

[texspeleo]

Well damn. All I got was a lump of coal.

 

[pescador775]

The Xstream is a different animal. I would be surprised if it didn't do something unusual. That is not necessarily bad. The second stage consists of a pilot valve (servo) and aspirator. The first stage uses a floating seat and ball bearing valve. Looks like it is well and strongly made.

 

[Tamas]

The initial "freeflow" that you mention at pressurization is normal for the Xstream as well as the Jetstream regs. It is not a freeflow as much as a shot of air coming from the servo valve as it pressurizes for operation.

The regs will come tuned for use, but if you want you can always have them looked at and perhaps tuned even more for an easier operation, but make sure the tech knows what he is doing as the Poseidon regs are not your run of a mill/garden variety second stage.

Enjoy the new regs, you will love them.

 

[Puffer Fish]

They are completely broken and absolutely worthless, but as a fellow SB member, I will take them off your hands...

Nice Christmas gift...

 

[Tamas]

They are completely broken and absolutely worthless, but as a fellow SB member, I will take them off your hands...

Nice Christmas gift...

oh-oh-oh! Me too! Heck I will even split it with Puffer here and pay for the shipping

 

[pescador775]

About freeflow: the Xstream second stage consists of two valves, a pilot valve and a primary. Engineers call pilot valves "servo" mechanisms. A servo is a small device which is employed to intitiate some action in a much larger device. For example, the small pony motor which was used in times past to start a much larger, Diesel engine could be defined as a servo; at least, the idea is similar. The famous V-1 cruise missile which bombarded London contained a servo mechanism to transmit commands from its gyro to the motors which rotated the missile fins. Today, the devices are widely used in pneumatics and hydraulics.

In a pilot valve like the Xstream, a tiny tilt valve is the principal element of the servo. It is normally closed as in all common second stage regulators. It produces its servo assist by raising or lowering the air pressure acting on the primary valve's diaphragm. In the Xstream, the diaphragm is not flat but rolled into a shape resembling a cigar stub. The function of the diaphragm is analgous to a common poppet valve. It controls the flow of air by expanding and contracting against the inside surface of an aspirator which contains many holes corresponding to the orifice in a normal regulator. Unlike most regulators in which the poppet is normally closed, the primary valve of the Xstream is normally open, eg, the diaphragm is contracted. Thus, when the second stage sees the initial air flow, the air flows freely through the holes in the aspirator and out the mouthpiece. In order for the diaphragm to become pressurized, expand and shut off the flow of air, the pilot valve has to remain closed so that it can create backpressure. However, the sudden onrush of air upsets this valve due to the venturi effect of air leaving the mouthpiece. Placing a thumb over the mouthpiece should shut down the venturi flow allowing the pilot to right itself, pressurize the primary valve's diaphragm and shut down the air blast. I believe this has been the general opinion reported above by those who use the Xstream. So, it does appear that the intial freeflow is normal and explainable.