Wanted Poseidon, Jet Stream, first stage

[rx7diver]

@Paul Desmarais,

I have responded to your DM.

rx7diver

 

[tbone1004]

I have shower head second stages.

Ideally I would like to buy a first stage compatible with those second stages.

Wish this had been posted last week before I got up here, I have a bucket of them at home and am leaving connecticut tomorrow morning. Be back in 6 weeks if some of the other guys can't help you.

 

[rx7diver]

The "Thor" was simply a Jetstream regulator attached to, typically, a 2940, a slightly more modern version of that first stage in your photos -- virtually, the same guts, though. Every Poseidon second stage can be used with any of their first stages.

Properly adjusted, there has never been a lack of compatibility with use of either a Cyklon or a Jetstream second stage with that first stage. I've used them, interchangeably, for years -- both the 2305 and the later 2940, seen below . . .

@Bigbella,

Thanks for this additional info. I was almost certain that I remember shower heads being paired with Cyklon 1st stages when I was contemplating purchasing my Odins (in the mid-1990's).

rx7diver

 

[Vq-1]

Found this set in the closet, Jetstream with Suunto gauges. Let me know if you’re interested.

 

[Paul Desmarais]

I have had my first stage and second stage serviced and the over pressure problem persisted. The tech mentioned the pressure differential between the first and second stages that @Nemrod mentioned

"The problem is that the Cyklon first stage is set to 166 psi and the Jetstream second stage regulator which has a built in pressure relief in the hose fitting is designed for 124 psi IP. The Cyklon first and second stages are not compatible with the Jetstream second stage. The over pressure relief is being activated by the high IP setting for the Cyklon second stage."

I don't know who is right, but I do know when I dive with the regs as is,the over pressure valves on the hoses bleed air and the valve on my BCD cannot seem to handle the pressure coming from the first stage, since it inflates on its own; which it doesn't do wwhen I used a borrowed reg.

 

[Paul Desmarais]

Found this set in the closet, Jetstream with Suunto gauges. Let me know if you’re interested.

Interested, depending on price.

 

[Bigbella]

I have had my first stage and second stage serviced and the over pressure problem persisted. The tech mentioned the pressure differential between the first and second stages that @Nemrod mentioned

"The problem is that the Cyklon first stage is set to 166 psi and the Jetstream second stage regulator which has a built in pressure relief in the hose fitting is designed for 124 psi IP. The Cyklon first and second stages are not compatible with the Jetstream second stage. The over pressure relief is being activated by the high IP setting for the Cyklon second stage."

Those integral OP valves on the older hoses were never rated for just 8.5 bar (123 psi); nor, for that matter, was the Jetstream (Odin) model second stage. It typically ran at 10 bar (145 psi or so), since the 1980s-on. Fully-functional hoses would vent at about 14 bar (just over 200 psi), in the event of a first stage failure -- just like the built-in OP valves on more recent first stages.

My Odins are happiest at 10 bar, per specs, and those hose OPVs are as quiet as the dead. If they had been absurdly rated for far lower, my regulators would have been venting like ill-tuned VWs.

Admittedly, Poseidon has futzed with their specs a bit over the years.

On a previous post, I mentioned the Thor, which was an early Jetstream second stage, attached to a so-called "300" model first (a 2940), usually associated as being a "Cyklon" second stage -- basically, your planned set-up, so far as I can tell. It was equipped with those OP valves in the hoses, just like yours. It was also rated for a maximum pressure of 12.5 bar (about 181 psi), according to the service manual.

I used that for set-up for years, without issue, and have lived to tell the tale.

No leaks; no incidents of overpressure. You have either an incompetent tech (which is far-too common nowadays, especially with the given brand) or perhaps even a damaged first stage; probably a poorly-tuned second as well. Could be a failing seat; crossed threads; damaged sealing surfaces; or, simply a filthily-performed rebuild -- something that Poseidon regulators just will not tolerate. All will negatively affect the IP.

Dollars to doughnuts, you have a creeping or improper IP from one source or another -- simple maladjustment; damage, dirt, metal shavings from ham-handed stripping; and if you’re truly set upon using Jetstreams, you’ll also need their specific hoses, since those for your Cyklon are also specialized and will not fit the other.

Below is an HP seat from a Cyklon 5000 -- touted as being "just serviced by a reputable LDS" -- whose IP had been all over the map, much like yours. It finally came down to a previous tech, either not cleaning anything very well, during an overhaul, and/or introducing metal shards after partially stripping some threads. That tiny splinter of brass in the notch, compromised the seal.

Upon initially opening the valve, it exceeded 14 bar (over 200 psi) within seconds -- and those hose-mounted OPVs were putting away.

Addendum:

Just looking at your regulator, once more, on the top-right, I can all-but guarantee that the IP is set too high -- just from the position of the "pressure adjusting screw" at its center. All of my 300s -- about a dozen in all, all properly set -- have that screw, just about flush with the cover for a properly-torqued valve housing (last photo), if not just slightly above; and none are that far below that surface, as yours appears to be.

It is a very thin screw in that older model and it takes little to over-tighten it . . .

 

[Tracy]

Are you looking for double enders or flat top first stages?
I have a couple of double enders laying around. I would take $75 each shipped in the US.

 

[Paul Desmarais]

Are you looking for double enders or flat top first stages?
I have a couple of double enders laying around. I would take $75 each shipped in the US.

I am honestly not sure. I need first stages compatible pressure-wise,with an IP pressure that won't trigger the OPVs in my first stage hoses. I want to use them withh the Jet stream 'shower head' style first stages

 

[Paul Desmarais]

Wish this had been posted last week before I got up here, I have a bucket of them at home and am leaving connecticut tomorrow morning. Be back in 6 weeks if some of the other guys can't help you.

If I have not found a solution by the time you return, let's connect and we can serve our mutual needs.

Thanks,
Paul