Poseidon XStream adjusting springs

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

IslandKraut

Registered
Messages
58
Reaction score
12
Location
Hawaii
# of dives
100 - 199
Aloha all,

I recently overhauled two Xstream first stages. Both are 90 degree models, with one being MK2 and the other Mk3.
After assembly and adjusting to the same IP, I noticed that the two adjusting screws (4798) are at different levels.
When I took them apart, I noticed that the pressure spring (4763) had different lengths...
Since I had a sinking feeling I might have mixed them up, I swapped them and now they are the same height, but one was clearly "shorter"...

I was not aware of such spring differences between the evolutions of the Xstream first stages - now I suspect a previously overtorqued spring.
There was another thought that the springs might be matched between the valve seat spring and the adjustment spring, but I realize the seat spring is prefixed in a certain spot by the upper pin guide being screwed down.

Anyone have any ideas?
(hitting up the usual suspects @rsingler, @tbone1004, @Bigbella)

Mahalo!

IMG_7545.jpg
IMG_7554.jpg
 
Provided that the regulators can be adjusted to a proper and stable IP, I wouldn’t concern myself too much with a slight variance in the size of the springs -- unless there had been some confusion between upper and lower springs (4763, 4764) whose diameters and sizes are slightly different (I cannot quite tell from the photo). I too had noticed a few differences over some twenty years of manufacture, including the still-marketed update kit for models whose serial numbers were below that of 310001, which featured a number of small revisions -- not to mention my first Xstream which did not even include an adjustment screw and whose IP was "preset" by default, into the 9.5-10 bar range . . .
 

Attachments

  • Screen Shot 2023-05-07 at 9.19.25 PM.png
    Screen Shot 2023-05-07 at 9.19.25 PM.png
    72 KB · Views: 76
  • Screen Shot 2023-05-07 at 9.22.30 PM.png
    Screen Shot 2023-05-07 at 9.22.30 PM.png
    557.5 KB · Views: 79
Is it possible to mix up the upper spring (4763) and lower spring (4764)? Are the springs in the picture the same diameter?

Barring that, the upper spring (4763) would appear to have been updated at some point, the kit to upgrade the really old non-adjustable models, includes a new 4763. One would think that means there was a change to it.

On 3 of my Xstreams, the adjustment screw 4798 sits just below the top, like the left pictured regulator. On my 2 DiveRite-branded Xstreams, the adjustment screw sits a little above, like the right regulator.

I guess if you are really worried, new upper spring is only $30: Silent Explorers Maple Grove Minnesot United States Online SCUBA
 
Thanks for the quick reply - no - not worried, and no didn't mix up the upper and lower spring. They are actually different in diameter and thickness of the coil. That said, I now realize that 90 degree and 180 degree models had different adjusting screws (albeit with different numbers) according to the SM. Now I don't have any of those, but maybe in previous service someone else mixed them up just as I feared I had.

BTW - the MK2 is SN 6xxxxx, so post upgrade, and the MK3 of course is.
 
https://www.shearwater.com/products/swift/

Back
Top Bottom