Scubapro G250 poppet assemby

[rsingler]

Were the unbalanced poppets referred to as "Duro Poppets" back then? I thought that term came into use with the replaceable soft seat.

The unbalanced poppets were originally hard seat unreplaceable. I think I referred to them as ORIG DOWNSTREAM. My earliest schematic is the M revision from Jul 88. I'm adding the N revision from Jan 91, which also has the hard seat unbalanced gray-green poppet, again labeled ORIG DOWNSTREAM.
When I refer to the DURO poppet, it is the white unbalanced with the replaceable seat, which seems to have first appeared in 1994, with the G-200.

 

[rsingler]

Here's an updated version of the spreadsheet, including the G260 data and some more old schematics.
I've discovered a G-250 inlet tube that retained the original part number, but had a clearly different shape. Arrrgh.
And also worth noting is that SP retained the same part number for both white balanced poppets - the single o-ring version and the newer 2-o-ring S-wing poppet.
I think we can presume the parts therefore are intercompatible. Can't wait for the official levers to arrive, to test this curly foot versus straight foot intercompatibility controversy.

 

[Rusty Shackleford]

Why do you want the plastic LP orifices as opposed to the metal ones? Cheers?

No risk of corrosion. They seem to work well.

I rebuilt a late-model G-250 before the quasi-250HP ones came out with the extra adjustment and dove it today.

Took you guys advice on the MK-20 that came with it. Checked the IP, it was rock solid. Didn't screw with it, just used it. The DIN saddle is two-slot so I know it was rebuilt at least once.

The 2nd had the late model poppet FYI.

 

[buddhasummer]

If regs are cared for properly i.e rinsed and soaked corrosion is not an issue. I think the plastic ones are false economy, I've found they don't tune as pecisely nor do they hold tune as well, not to mention they are easily damaged. Obviously YMMV. Message me with what you're looking for I might be able to help.

 

[Couv]

I'm ordering one of each from my supplier. Will post pics and measurements.

You may not like what you see. Thanks to your post I just sorted through my curly feet levers and found a distinct difference in the ones I have. Below are a couple of pictures; I believe the levers on the left are aftermarket-the levers on the right are SP originals. The aftermarket levers have a different profile. The SP levers look much like the older lever except the feet. I don't think I've installed the aftermarket levers into a regulator yet; hopefully I'll get around to that soon and update.

 

[rsingler]

The aftermarket levers have a different profile. The SP levers look much like the older lever except the feet.

View attachment 421091 View attachment 421092

That's great news, couv!
All my objections were based on the angle of the aftermarket curly feet, and the resultant effect on lever height, and therefore cracking effort.
If SP's curly feet are different, the question may be resolved, and all of you who said they worked fine will be right. Some of our schematics suggest that should be so.
The only downside is that I might have to re-bend or discard all my aftermarket levers. Caveat emptor!

 

[Couv]

No bending necessary. I have interesting (to me anyway) and encouraging news. I ran a few experiments using the same regulator body, s-wing poppet, spring, orifice, etc. with the only difference being the levers. I used the original SP lever, then the SP curly foot lever, finally the aftermarket lever. THEY ALL worked just fine!

At first I had my doubts about the aftermarket as it "looks" odd and high, but that is mostly an illusion. Here are a few pix. The last one pretty much says it all, it is the aftermarket lever after tuning, with the cover in place etc. BTW I believe after the diaphragm, rubber & metal covers, and band clamps are installed, if it takes more that a very slight adjustment something is wrong. I did not have that issue with any of the levers.

The first three pictures are each of the levers covered by the diaphragm. Original, then SP curly foot, then aftermarket. Each picture was taken before tuning. Next are pictures after tuning. (Missing is the a picture of the original lever after tuning, but we all know what that looks like.) Note the pictures show the diaphragm skirt mates all the way around the body with no gap. The last picture shows the cracking effort of the BA with an aftermarket lever after the covers and clamps are installed.

 

[rsingler]

No bending necessary. I have interesting (to me anyway) and encouraging news. I ran a few experiments using the same regulator body, s-wing poppet, spring, orifice, etc. with the only difference being the levers. I used the original SP lever, then the SP curly foot lever, finally the aftermarket lever. THEY ALL worked just fine!

At first I had my doubts about the aftermarket as it "looks" odd and high, but that is mostly an illusion. Here are a few pix. The last one pretty much says it all, it is the aftermarket lever after tuning, with the cover in place etc. BTW I believe after the diaphragm, rubber & metal covers, and band clamps are installed, if it takes more that a very slight adjustment something is wrong. I did not have that issue with any of the levers.

The first three pictures are each of the levers covered by the diaphragm. Original, then SP curly foot, then aftermarket. Each picture was taken before tuning. Next are pictures after tuning. (Missing is the a picture of the original lever after tuning, but we all know what that looks like.) Note the pictures show the diaphragm skirt mates all the way around the body with no gap. The last picture shows the cracking effort of the BA with an aftermarket lever after the covers and clamps are installed.

Great work, couv!
You da man!

 

[Couv]

Oh, one thing I forgot to mention is your idea re the leg spread. Yes, the aftermarket lever's legs are slightly further apart than the original. If you hold a poppet upside down and hang the lever from it (basically turning the system over) you can see how much to close the legs. Of course you want to put the bend as close to where they already make a right angle as possible.

 

[halocline]

I had no idea there were aftermarket levers, who is making those? Anyone we know?

I think the curly feet ones have a smoother movement on the poppet than the square feet ones, but I'm not sure why. The tail of the curved feet could kind of grab onto the inside of the barrel and prevent spreading of the feet as the lever pushes on the poppet. There might also be something to the curved surface more smoothly moving the poppet as the angles change (the lever gets depressed).

That's quite an array of levers, Couv.