Aqualung Titan LX dry-seal 1st-stage membrane 'posture' ?

[scubafanatic]

So, I have several assorted diaphragm 1st-stage regs, and I noticed the little 1st-stage membrane that dry seals the 1st-stage is bowed out in the 'rest' position. ('rest' position defined as reg off tank @ 0 psi. I thought I remember somewhere that this little membrane should be 'puckered in' (like a little dimple) when the reg is @ 0 psi, and then when the reg is pressurized, the little membrane should 'bow outward'. Is my understanding correct, because if it is, it appears I need to have the reg set up properly by a knowledgable reg tech ?

Thanks in advance,

Karl

 

[Fishpie]

The 1st stage needs to be pressurized when the dry seal diaphragm is tightened down to correct this condition.

 

[Bubbletrubble]

Fishpie is correct about how the environmental diaphragm is supposed to be installed. However, depending on when this occurred, it's possible that other issues may have caused it.

Was the first stage recently overhauled? If this is the case, take it back to the reg tech and ask him to fix it. This repair shouldn't cost you a dime since obviously something was done incorrectly during the overhaul.
How long have you noticed that the environmental diaphragm is distended?

There are several possible fixes for a distended environmental diaphragm:

1. First stage port plug o-rings are worn/damaged. Replace the o-rings.
2. Diaphragm is worn/damaged. Replace the diaphragm.
3. Environmental diaphragm is worn/damaged. Replace the environmental diaphragm.
4. Diaphragm retainer is loose. Tighten it (with the system pressurized).
5. Diaphragm sealing surface is damaged. Replace the valve body, diaphragm thrust washer, or spring retainer (whichever part is damaged).

Of the possible problems, I'd say that #5 is the least likely but most expensive to fix.

If it's about time to overhaul the reg (1-2 years since last overhaul), I'd just have it serviced and then keep an eye on it. During a standard overhaul, the o-rings, diaphragm, and environmental diaphragm are all replaced and the diaphragm retainer is properly installed. You could try to replace the port plug o-rings and re-install the diaphragm retainer yourself...but if this sounds too complicated, it's probably best to take it to a competent reg technician.

FWIW, I've never worked on this particular reg before, but I'm familiar with the Apeks first stage design which is fairly similar. It's simply how I would troubleshoot this problem.

Good luck.

 

[scubafanatic]

Thanks to both of you gentlemen! A bit of reg history: reg is a few years old, has always been a back up reg, I've never actually used it on a dive trip (although I have loaned it to a few divers in need on assorted dive trips over the years as part of save-a-dive kit) I've only personally used it at the bottom of a dive shop's swimming/training pool once for maybe 15-30 min, about 15 months ago, just as a 'I'm curious how it feels' test...the reg worked, but I don't remember being very impressed with the performance, I attributed my impression to my being used to diving top-shelf regs (Apeks XTX 200/Atomics). A few years ago the reg was significantly damaged by impacting a steel dive boat deck when a dive buddy's tank popped loose and her whole set up smacked the deck. The reg was repaired by a very competent dive shop, the entire 1st-stage reg body was replaced, and if memory serves, the dry-seal kit was added after the accident as I used that opportunity to upgrade the unit. I'd characterize the unit's condition today as essentially 'mint', (as in you can't even tell the unit has ever been used) just installed all new MIFLEX hoses/Poseidon spg/etc. Although it's been about 3-ish years since the repairs/service, if memory serves, the 'diaphragm' has always been bowed-out, it's just that this is a 'reserve' reg, so attending to it hasn't been of the highest priority and I'd sort of forgotten about it, until I recently 'MIFLEXed' it and renoticed it. I've printed out this info to take to my reg tech this weekend for inspection......if I had to guess, it's something really simple, namely a failure to adjust the reg properly while under pressure, but I've printed out all Bubbletrubble's good info/details, incase it's something more major.

While I know the Titan LX isn't quite as good as my Apeks/Atomics, it is my distinct impression it should have felt a lot better than my impressions at the bottom of that pool, and I just can't believe my Apeks/Atomics are THAT much better, the performance gap was too wide, such that I'd not really want to that the Titan LX for a dive unless I really had to.

Thanks again,

Karl

PS...the dive shop that worked on it back in the day is out of business about 3 yrs ago....not through any defects in servicing as I was always VERY impressed with the level of quality of work done on my Apeks XTX 200's there...just a rough economy...and I still miss that shop! I even loaned an Apeks XTX 200 to a lady with Scubapro reg probs on a liveaboard 2 1/2 yrs ago, and she was completely blown away by the stupendous performance of that reg, absolutely couldn't believe it...so that shop knew how to tune a reg!

 

[Bubbletrubble]

Karl, you mentioned that the reg wasn't performing very well. Did you ever get a chance to check the i.p. on the first stage? I'm also curious how the second stages were breathing. I have dived my Apeks first stage with a distended environmental diaphragm for the better part of a year (about 30 dives) and it continued to perform very well (i.p. still within normal range and cracking pressure still the way I like it). When the i.p. crept up a little too high (over 150 psi), I started to get some freeflowing in the second stages that wouldn't stop even when I cranked down the inhalation adjustment knob completely. I could have compensated by adjusting the lever height a little...but figured it was time to just overhaul the sucker. It had been 2.5 years and about 150 dives since it's last servicing. I share this info to let you know that a distended environmental diaphragm doesn't necessarily cause a noticeable deterioration in reg performance. At least that's been my experience.

If you don't have one already, you should really buy an i.p. gauge. I think all reg owners should own one. It really helps when troubleshooting reg issues.

I wonder how your Titan LX will breathe once it's overhauled and tuned properly. Let us know how everything turns out. Good luck.

 

[Bubbletrubble]

*double post*

 

[scubafanatic]

Karl, you mentioned that the reg wasn't performing very well. Did you ever get a chance to check the i.p. on the first stage? I'm also curious how the second stages were breathing. I have dived my Apeks first stage with a distended environmental diaphragm for the better part of a year (about 30 dives) and it continued to perform very well (i.p. still within normal range and cracking pressure still the way I like it). When the i.p. crept up a little too high (over 150 psi), I started to get some freeflowing in the second stages that wouldn't stop even when I cranked down the inhalation adjustment knob completely. I could have compensated by adjusting the lever height a little...but figured it was time to just overhaul the sucker. It had been 2.5 years and about 150 dives since it's last servicing. I share this info to let you know that a distended environmental diaphragm doesn't necessarily cause a noticeable deterioration in reg performance. At least that's been my experience.

If you don't have one already, you should really buy an i.p. gauge. I think all reg owners should own one. It really helps when troubleshooting reg issues.

I wonder how your Titan LX will breathe once it's overhauled and tuned properly. Let us know how everything turns out. Good luck.

yeah, I probably need to buy an IP guage, just for my information, as I have no real plan to service my own regs, but just to see if they're 'healthy'. There's no freeflow issues, but I have no frame-of-reference, so I have no real idea of how a Titan LX should feel if operating @ 100%...I've never compared it to another Titan LX underwater (or above water either). I just know it's really not in the same league as my top shelf regs...not even close...so either my premium regs ARE way better, or the Titan LX is out of spec somehow, especially if the difference is obvious in a swimming pool sitting on the bottom. Honestly, I doubt an 'annual' is needed, that was done a while back, filter spotless, very few hrs on the unit......I'm putting my $ on improper set up, I'm gonna see if the reg tech can mess with that first...then we'll do an 'annual' as plan 'B' as needed.

I'm planning for the Titan LX to be one of my 'simple' light travel regs, so that's why I'm interested in seeing it at 100% performance.

Over this past year I'm completing numerous gear projects, including modernizing/upgrading (6) complete reg sets:

Atomic T2
Atomic M1
Apeks XTX 200 (2)
Mares Ruby
Aqualung Titan LX

Thanks again!

Karl

 

[Bubbletrubble]

I bet that the Titan LX will breathe very nicely once it's overhauled and tuned properly.

Even if you don't plan on servicing your own regs, you should download the reg technician manual to learn how to tune the first and second stages properly. It's very easy to do with standard tools and an i.p. gauge. If you can operate an allen wrench and a flathead screwdriver, then you can tune a reg.

That's quite a hodgepodge of regs. Perhaps you should sell some off and standardize with one brand. It would make troubleshooting and having spare parts on hand more convenient. Good luck.

 

[scubafanatic]

I bet that the Titan LX will breathe very nicely once it's overhauled and tuned properly.

Even if you don't plan on servicing your own regs, you should download the reg technician manual to learn how to tune the first and second stages properly. It's very easy to do with standard tools and an i.p. gauge. If you can operate an allen wrench and a flathead screwdriver, then you can tune a reg.

That's quite a hodgepodge of regs. Perhaps you should sell some off and standardize with one brand. It would make troubleshooting and having spare parts on hand more convenient. Good luck.

well, speaking of hodgepodge, I won't even mention my Poseidon regs! I really have standardized on Apeks and Atomic, the Mares and Aqualung regs are significantly older (although still in very good shape, and the Mares just got back from an annual, upgrade to tri-material HP seat, and upgrade to dry sealed 1st-stage, so although it's approaching 10 yrs old, I think it's competitive with most new regs out there performance wise.) I don't really want to sell any of these regs, as they are all in very good condition and are worth more to me as regs than the amount of $ they'd generate on E-Bay. Strangely enough, having a variety of brands has helped me with servicing as I can diversify my sources of service/repairs so I'm not as reliant on a single manufacturer, although I'd agree with you if I were servicing my own regs.

 

[Fishpie]

btw
The LX 2nd stage is essentially the same reg as any other Apeks 2nd stage.