Used Poseidon Xstream set Advice needed

[CandiveOz]

Divers,
I came across an opportunity to purchase two used sets of Xstreams. I don't know too much about these regs except they do have a good reputation; hence my question on this forum. Based on the 6 digit serial number stamped on the first stages it looks like the regs were built in 2002 and 2003. I'm not sure what models they are. Both are chrome finished but one has a black "cage" around the outer spring. It looks like they have the original set of hoses.

Does anyone know what first stage model was produced at this time? I assume parts are still available for these regs but I was wondering if there is something I should be aware or investigate of before making a final decision.

Your advice and comments will be much appreciated.

 

[Magnus Lundstedt]

I assume parts are still available for these regs but I was wondering if there is something I should be aware or investigate of before making a final decision.

Poseidon still have parts for their regs from the sixties.

The only thing i have heard it can be hard to get parts for is the now obsolete neptune triton second stage.

 

[CandiveOz]

The only thing i have heard it can be hard to get parts for is the now obsolete neptune triton second stage.

Yes, I did come across a set with a Jetstream and Triton occy but after reading a number a posts on this forum I'll give that set a miss. But for those who like nostalgia and a unique looking reg, plus are capable of servicing it to keep it functioning it may be an option but I don't fit in that category.

 

[rsingler]

Well, you're right about the XStream. In my opinion, the XStream first stage is the most sophisticated diaphragm regulator in the world.

Your used set will likely need an upgrade to the ruby ball that replaced the stainless one. I'm not quite sure what you mean about the black cage, but the flexible diaphragm is very reliable.
The set is easy to service, and with Salt Blue taking over parts supply, it's gotten much more responsive than it used to be. Of course, Poseidon parts are more expensive than other manufacturers, but not outrageously so.
For a reg that's certified to 200m, you really can't beat a properly tuned Poseidon set.
My 2 cents, from a guy certfied by Atomic, Scubapro and Poseidon for service. Let me know if you are maybe interested in my servicing your gear.

 

[CandiveOz]

I'm not quite sure what you mean about the black cage,

Here are some photos. I'm not sure what the part is called "the cover" of the TDA (ThermoDynamic Anti-freeze)?

Your used set will likely need an upgrade to the ruby ball that replaced the stainless one.

So what year did the ruby ball come out? According to the manual, these regs have a 6 digit serial number and apparently the first digit represents the year so the two sets I'm looking at must have been made in 2003. Also on each first stage they have an alpha numeric; 4791BK and 4791GY. I think this refers to the second stage because one is black and the other is gray. I found a third set with the marking 001-47 . I'm not sure what this refers to but the first number of the 6 digit serial number is 6 so I assume this set was made in 2006.

As for the first stage model, I understand its located in the Din? Is knowing the model number important or are these 1st stages basically the same?

Also, I have been reading that the over pressure valve (OPV) in pre 2008 models are actually on the hose rather than the first stage. I'm a little confused. Is the OPV at the end of the hose connecting to the first stage or at the end connecting to the second stage? And I assume if I want to change the hose to a Miflex, I'll have to buy a special adaptor for these pre 2008 used models.

Oh @rsingler, if I get any of these sets, I would love to have you service them but unfortunately I reside in Australia.

 

[Caveeagle]

You could have a reg that has been upgraded with the adjustable cover. Early versions did not have the Allen key cap to adjust the IP.

If you don’t have an OPV machined into the bottom of the first stage you have a couple options. The original hose would have had the OPV built Into the hose end. You can see the spring and seat from the inside if you remove the hose from the second stage. You have a couple options for new hoses,

1-Stick with the Poseidon hose (with integral OPV)
2-use a second stage adapter with integral OPV. Omni swivel makes a couple nice ones in both fixed and swivel versions, *these allow use of normal hoses, or myflex
3-get an actual OPV to screw into an unused low pressure port.
4-use a safe second(octopus) that’s a more normal downstream valve design that will functon as an OPV. ***this is my least favorite option, because I don’t recommend mixing reg brands unless you really know what you are doing. Ie: can validate breakthrough IP on that safe second.

(#2 is my preferred option as I have a few of the early first stages that don’t have OPVs)

 

[CandiveOz]

Hi @Caveeagle
Thanks for outlining the different OPV setups. # 2 is the best option but I may have to order the integrated OPV adapter from overseas. I am able to source a standard adaptor from an Australian supplier and I just need to contact them if they can source the one you recommend.

Now in the off chance I can't source the integrated OPV adaptor could I swap the hose with the OPV from the first stage to the Xstream occy and use a regular adaptor with a miflex hose on the main second stage to achieve the same result? I'm assuming (and I may be wrong) that the hose to the second stage contained the OPV and the hose to the occy didn't. Or did both hoses have an OPV?

I don't require miflex's on both hoses; just the main second stage.

On second thought I guess not since the hose will be shorter....

 

[tbone1004]

@CandiveOz at that age, the likelihood of having the OPV's is small.

@Caveeagle 's suggestion of using the omniswivels is by far the best option for you as it allows you to use standard hoses and it alleviates the stupid OPV's on the body of the first stage that all leak.

Omniswivel has a distributor and several dealers in Australia. They will likely not have the adapters in stock, but you can use the hoses they came with for now.
Find A Dealer — OmniSwivel International

in terms of what needs an OPV, the entire system only needs one, and an OPV is just a downstream valve. That can be one integrated to the first stage, one screwed into the first stage, a standard second stage, or the Poseidon hoses. All of the Poseidon hoses have the OPV as standard and I wouldn't prioritize getting adapters until you need to change the hose or need a different hose length.

Omniswivel sells 3 different adapters for the Jetstream/Xstream. Straight, 90* elbow, and ball swivel. I use the ball swivels on all of my regulators *close to 20 at this point* out of personal preference for comfort and believe they do a lot more than a miflex hose for overall comfort.

 

[CandiveOz]

Hi @tbone1004
Thanks for the link and clarification on the OPV, its obviously not a show stopper in buying a used rig. @rsingler mentioned that when I get my regs serviced, the steel ball will/should be replaced by a ruby one? Why does this sound like an expensive upgrade to me? obviously once replaced, I assume the ruby will last the life of the rig. When buying used rigs usually the unit has been sitting around for a number of years and needs a service. Its a cost I have to take into consideration when buying used vs new and it will have a impact on my offer price. So I have to determine the cost of service for Poseidon in my local area. Also, I have a dive buddy in my club that dives a Jetstream, so I'll probably borrow it to do a shore dive to get a feel for the reg. Lastly, @tbone1004, since you own 20 regs, you probably know a fair offer price for one of these 15 year used kits.

 

[rsingler]

The ruby ball really makes lockup a lot crisper. Unlike the steel ball, it doesn't scratch from microscopic grit from tank oxidation that makes it past the sintered metal filter.
And yes, it lasts the life of the reg.

Downside as always with Poseidon is the cost. List US$47.