Healthways Scuba and Gold Label Valve Variations

[vance]

I was just skimming through the various HW Scuba threads on here, some of which are very lengthy, and couldn't find all of the posts about the different valves and internal parts used with the Scuba series of double hose regulators. So, I think it would be a good idea to make a reference thread that consolidates this information.

This was prompted by another adventure with a rebuild, a GL this time, caused by part variations I, at least, didn't know about or expect.

I will move or copy old posts over time, and try to get it all in here.

It appears that the Scuba got a long or short valve during its entire run. Every Deluxe I have seen is short, every GL has been short. 

This shows the different valve lengths. Note the different threads:



The different plungers:









I did not keep track of which restrictor plate was in the the short/long versions, unfortunately. So, I don't have any idea which plate was used when. There are at least 3 different plates.

(A restrictor plate provided a "reserve" function, pre SPG days, that would alert the diver that air was at around 500 psig. This tiny aperture made it hard to breathe when the tank pressure got low, so, in order to continue breathing, one had to ascend to the surface.)

However, the machined restrictor plate does not compensate for the length of the valve bore. It is cut in the spring seat so it is essentially only as thick as the stamped restrictor plate. The bore length difference is taken up by the different nylon plungers which were machined to seat the spring high or low. 

Machined restrictor "K":



Stamped plate "K":



Stamped plate "J":



The "J" plate did not provide a reserve function. It is only there as a spring and o-ring carrier.  I wouldn't be surprised if there was a machined "J" plate, but I've never seen one.

So, one has to be careful when replacing the nylon plunger in a Scuba. The short plunger in a long valve will provide much less spring pressure on the plunger, causing very floppy feeling lever action and a very low cracking effort which may cause problems. (EDIT: The opposite could happen as well, with a long plunger in a short valve, the cracking effort would be considerable, if the thing could be assembled at all!) 

I am surprised to have never seen a reference to the different valves or plungers anywhere. It is an obvious difference, and means that you can't just switch valve parts around willy-nilly! 

[vance]

I rebuilt a GL valve using what should have been the appropriate parts from my parts bag. No matter what combination of internal parts I installed, including a whole set of internals from another, working GL nothing would work correctly.

The problem was that the valve would not lock up and leaked air through the venturi like crazy. The problem was two things: the valve body specs are slightly different, as well as the pin's. The pin was holding the seat open. I ended up having to machine a spare pin so it would work.

It turns out that there are at least 3 different HP pins. The difference of two are obvious, but the third has just slightly different dimensions at the needle end to make the square section shorter.




The upper photo is a GL pin. Note the cut in the center of the square section. That opening keeps the edges of the square from blocking the venturi hole. I machined that relief and cut the bevel at both ends of the square section a few thousandths on the spare pin. That allowed the seat to close completely.

[nikeajax]

Huh, good to know! I wonder if they sourced a different contractor or something? Yeah, our Healthways threads are monsters, aren't they If I can help in any way, let me know...

JB

[nikeajax]

Oct 1, 2018 8:43:30 GMT -8 vance said:

I am surprised to have never seen a reference to the different valves or plungers anywhere. It is an obvious difference, and means that you can't just switch valve parts around willy-nilly! 

So this would more than likely mean that this is the case for Sportsways-Waterlung gear too: no?

JB

[vance]

Yes,
I just rebuilt a NED HTII with different valve internals than my other two. Check that out here:

vintagescuba.proboards.com/thread/5323/ned-hydrotwin-ii

[vance]

Dec 17, 2020 10:46:40 GMT -8 nikeajax said:

Huh, good to know! I wonder if they sourced a different contractor or something?  

Could be, but I think the length and material of the bodies was changed mainly due to cost cutting. The machined restrictor plate being replaced by a stamped one had to have cut labor costs by a bit, too. 
 

[vance]

I have been investigating the difference between a Scuba/Deluxe valve and a GL valve.

The GL has a flat cap on top with a soldered on, an integrated venturi nozzle, and a jet drilled into the side of the body.

The body is much like the older style, but machined differently at the top. I believe the GL is machined with the cap (I used to think the cap was soldered on). There is no bevel-cut on top, since it is no longer necessary. They drilled into the side of the valve for the jet, and soldered the tube on. 

[nikeajax]

So, probably for the same reason they got rid of their original-Scubair, and changed it to a piston reg.

Maybe you know the answer to this: the Scuba had two different types of band-clamp: is this the original style?



JB

[vance]

The steel clamp is early. I prefer them to the chromed brass later one. The brass ones break pretty easily.