Sherwood SR-1 "Problems" - request for first-hand experience

[rhwestfall]

(and say "hi" to Mark and crew for us!)

 

[BoltSnap]

Yes sir

Have great time there with lots of awesome diving. You now have to report on the regulator and on the diving in Curacao, double report!!

 

[lexvil]

Hope to see something like this again!

but just the freedom of warm water diving is it’s own reward. Also hoping for a positive regulator report.

 

[Mobulai]

Zombie thread revival (I was debating if I should start a new one or not)

So a few days ago I got me a couple of SR2s from local classifieds (been eying them for a year now and finally found a goo deal), and already sourced a couple of service kits (thanks @axxel57 you’re my guardian angel)

First sign of confusion was that the regs were branded (and also the previous owner sent all past service / purchase documentation) as SR2; when I looked at the microadjust on the 2nds they were hex (like SR1)

I decided to hook them up to tanks to test them (I was mainly worried about IP)
I have a 10l w 50bars, and a 2l w 170bars

1st reg did quite alright, 130-135psi on both tanks — solid since its last service was 3 years ago (showing same IP on docs)

The 2nd set…
very confusing results that I can’t make much sense of:
On both Tanks, various tries:
Initial lockup at 145psi, within 30s 150psi, 5 mins later 156~160, 20~60mins 170psi
Ok, sounds like creep…
Beyond the 60mins it settles back down to 145-155psi.. is the 2nd leaking even tho I can’t hear it?

I did these tests with no spg, I also close the tank (and reopen momentarily every 5-10mins) not to drain while unsupervised
So I decided to repeat the tests, with spg (as HP accumlator/mini tank) and an inline shutoff on the 2nd (yes risky)

Same exact results (shutoff closed)
But the SPG was the big tell..
Over the last test (still ongoing for 2 days now) the „tank“ went from 170(ok lost some so 150)bar to 100 bars (resl tank still at 170-150); every couple of hours I did a open/close, no purging, with IP maxing out at ~172psi; then over last 24 hours I just left it completely tank closed, till it got to 10 bars on spg

IP is „stable“ at 145psi at the moment

Besides the high IP (right from the start)
is that a „leak“ leak, is it on the HP side? The „ambient chamber“ vent hole thing?

Is there something about the sealing mechanism that has to do with this?
I read in general about Sherwoods „burping“/venting

I have to admit that I did „push on“ the environmental diaphragm to check response and saw like 3-5psi increase

I know my next step is dunk/bubble test; just looking for ideas on what’s happening

I also lnow that IP is out of spec, so I’ll look at that piston tip when I open it

———————

Since the original thread question is SR1 issues, and given the hex microadjust I guess I have actual input to @rsingler ‘s original query:
The only issue, right out of the shipping box I noticed right away was the combo adjustment knob: it screeched like death on train tracks and was very janky to maneuver (I had to press on it so that my turning motion translates to actually pushing the spring/Venturi); definitely needs lube

The Venturi deflector mechanism seems very flaky gotta say; but that seems the same in SR2 schematics as well
I honestly don’t know which one I have

I don’t like this knob at all; but the 2nds didn’t leak one bit, props for that floaty orifice

 

[rsingler]

That's definitely an SR-2 case (compare the schematics). It may be that it was very early, before they used up old stock on the microadjust. They never changed the part number, btw. But the hex doesn't look stripped, so if it moves, it doesn't matter. Just lube that whole assembly. It's like the Aqualung Master Breathing System. Not my favorite, but it works.

Comparing schematics, the only significant thing is that they revised the tiny poppet stem oring. But a new kit should revise that automatically.

I never did find out what the change was, if anything. I took my first Sherwood certification just as they were introducing the SR-2, but what they said in class never appeared on the schematic. I think SR-1 and SR-2 seconds are functionally identical, but a Sherwood maven can correct me, if I'm wrong.

As for your first stage, sure sounds like a little piston scuffing. And your pressure drop might indeed have been the piston shaft/o-ring.
Funny thing is, some leaks in long storage regs just seem to disappear with a little use. The piston shaft oring may have taken a set, but a little motion helps it seal again.

So, who knows?
Keep us apprised!