Well, I didn't have a way to measure the o-ring on the seat exactly, so I just eyeballed an approximate replacement out of the extra orings I had lying around. It worked. No leaks. If I can, I will be testing it out in the pool tonight.
Well, it shouldn't shudder. I checked the text in Basic Scuba, and they have only one entry which may pertain. It says, for "Regulator free flows easily" that the answer may be that the "Demand diaphragm may be upside down," and recommends "Check diaphragm installation with Figure 3-18." The diaphragm should have the "bell" out, toward the exhaust box. So try that and see if that's what may be causing it to "shudder."
John C. Ratliff Diving since 1959, at age 13. Haven't stopped, and still enjoy getting wet.
Actually, upon more thought, I think it is the opposite problem. It's not freeflowing, and in fact didn't freeflow when I was face up, which makes me suspect that I need to adjust it. I think perhaps that it was barely opening the valve at all. I'll experiment some, and report back.
I guess my Mistrals do what you could say "shudder" when I inhale slowly (dive buddies just don't understand- it's usually annoying to them, but it's kind of musical to me ). They even out when I'm sucking air though. But they are a single stage and that seems to be the nature of them due to the drastic pressure reduction involved. Basically, the diaphragm flutters because it is vacillating between over-pressure and under-pressure in relation to ambient.
Fluttering or shuddering should be more easily adjusted out on a two stage reg. I have never dived a Healthways, but if you were not getting plenty of air while inverted you may want to check your IP and especially your second stage seat/linkage adjustments (try raising the levers a little).
I think that Duckbill hit it correctly, and that you need to raise the levers. This is not the USD system; the Healthways lever system, especially on the older two Scuba regulators, needs to have the levers adjusted as high as they can be adjusted without having the levers contact the diaphragm when the case is installed. Use an Allen wrench to keep the pin oriented correctly when you screw it in, and tighten the locking nut, or the levers will go out of adjustment as you wrench down that locking nut. But get them as high as possible without free flow when the top box is placed on the regulators and clamped down.
The Healthways regulator won't vibrate like the Mistral when breathing it out-of-water. It should produce a smooth flow, but not a "gush" as the venturi is very subtile on this regulator (there is only a slight effect due to the valve design). This is a characteristic of the Mistral (the vibration out-of-water), and not the Healthways regs.
John, You're right. The Mistral vibrates like crazy when breathing slowly out-of-water. The noise in-the-water is somewhat different, I guess more like a "gush" like you said, sometimes a groan at the beginning of an inhalation. Thanks for bringing that up. I didn't make that distinction and I should have.
Silly humans, fins are for fish. Mammals use flippers.
This is a very heavy shudder. It feels like my chest is vibrating too. It did not happen at all when I was swimming on my back(and also didn't freeflow), so I am pretty sure it is just an adjustment issue. It also never happened on the surface.
I had three very nice dives yesterday in my favorite hole, the High Rocks area of the Clackamas River, near Portland, Oregon. It was warm, and the lifeguards had measured the water temp at 63 degrees, 5 degrees warmer than last weekend. So I wore only my wet suit tops and hood. I dove the first dive with my Scubapro A.I.R. I regular, just to remember what it's like with a single hose regulator. I took my UW camera (Canon New F1 in an Ikelite housing), but did not see my redside shiners, which is what I wanted to photograph. I took a few photos of sculpin, and some of the soft drink cans in the debries pile, surfaced and climbed out to go to the car.
I wanted to dive the second dive with my Healthways SCUBA Deluxe regulator (Blue Label). I wanted to evaluate the exhaust system of this regulator, which has a mushroom valve. After the problems I had with the original Healthways SCUBA regualator (documented above in this thread), I felt that the $20 I had spent at a LDS for this regulator would be an improvement. I dove it with the Hope-Page mouthpiece, and without an intake non-return valve. This turned out to be a mistake. I dove into the current, got to the bottom, then noticed that I had a real problem with the exhalations. The exhaust mushroom valve was effectively blocked by the main diaphragm, which was slightly pressurized by my exhalation.
I swam downstream to find my exit, and found my redsided shiners. They were in deeper water, mid-column, feeding instead of mating. So I watched them for about ten minutes, even with the exhalation problem. I found that if I tipped myself to the left a bit, I took some of the pressure off the mushroom and it was tolerable. The fish got right up to my mask, and got some good observations.
I finally decided that I could exit, go to the car, change tanks to a single 80, and come back to get the photo. This I did, and on the third dive used a Dacor Pacer regulator. I got some good photos (I think--they have not been developed yet). But I did note that it was more difficult with a single hose regulator, as I had to hold my breath much more than I did with the Healthways SCUBA Deluxe regulator.
Today, I changed back to the original Healthways Scuba regulator, as that exhaust really did not hack it for me. I hope to re-unite with a Healthways SCUBA Deluxe regulator that I had in the 1980s, which is now at a dive shop in a different city. I remember that the Healthways SCUBA Deluxe (Gold Label) had a small metal projection that kept the diaphragm from impinging upon the exhaust mushroom valve. This makes me think that, of the Healthways SCUBA regulators, get either the original one, or the SCUBA deluxe Gold Label. The middle one has real problems with breathing resistance on both inhalation (using the original hose/mouthpiece system) and exhalation under some circumstances. I tried the regulator today with the original hose/mouthpiece system and the non-returns in the mouthpiece, and the diaphragm did not impinge on the exhaust mustroom. But the tradeoff was that the non-returns caused a much-increased inhalation resistance.
I've now rebuilt two of the blue label SCUBA models. However, the adjustment screw on the first one I had was badly stuck, and I ended up stripping it accidentally. So, I need to either find a new screw, or make one. That was the one that I mentioned shuddering above. The second I took to the pool last week. It breathed well, especially compared with the DA I keep messing with. The only problem I had was that I switched from the older style hose clamps to some new ones, and the 1" side didn't seal well and leaked. I also need to fabricate a new duckbill, since mine is on its last leg. I'd also like to make or purchase a new diaphragm. Mine are old and a little stiff, and I think that a new silicon one would make a world of difference.
Well, I've decided to make a slight modification to the regulator body. I'm having a machine shop drill a new set of holes for mounting the levers. Most of the air seems to escape around the sides of the levers. So, I am going to try realigning the levers, to have the air directed into the intake hose. Any thoughts on this? I'll give my impressions when I get the body back and get to test it.
How do you make a duckbill? My duckbill on my Healthways has see better days. The secondary exhaust diaphragm has a small hole, I was thinking about using neoprene cement to patch the hole. Is this a bad idea? I am open to suggestions how to repair my duckbill and secondary exhaust diaphragm. Does anyone have a spare Healthways main diaphragm that they are willing to part with for a reasonable fee? I have a company that may be willing make some, I would hate to lose my only diaphragm. I ordered an extra USD duckbill, I will see if that can be adapted to the Healthways.
Well, I've heard of people doing it for one off parts, so it can't be too hard. I'm going to experiment with some liquid silicone rubber that I have. I'll let you know what I find out. Yes, I can't see how patching the exhaust diaphragm with aquaseal or the like would hurt. I would just patch it.