Newly serviced regs break on third dive

[Nemrod]

Modern regulators are designed for obsolecence. Intended to be discarded every few years. So I gather, like most things today, service is problematic at best and dangerous at worst thus the continuing trend towards throw away regulators. Use a few times and toss'em. I see torque putty on some new regulators, once the indication is broken the manufactuer can claim the unit was "serviced" by incompentent persons, tampered with, modified and therefore they have no liability. They prefer you just purchase another or at least return it to them for repair which I think is rarely supported by most such companies due to expense.

"I small suggestion -Never, never buy something that your life may depend on at the suggest of someone on a forum."

Well, making an informed decision is always good but the assumption that all internet advice is bad and that all LDS advice is good is not realistic. For years and years people have built their own boats, built race cars, built airplanes, built their own radio sets and all manner of gizmos and yet for some reason people get all crazy over servicing their own regulators. The things (regulators) are simple--SIMPLE---many people have the skills and knowledge young and old. Besides, all this safety stuff is way over rated, live dangerous, die free. N

 

[Creed]

I small suggestion -Never, never buy something that your life may depend on at the suggest of someone on a forum.

Discussion is great, but if you have to ask what size is needed, you are most likely not a candidate for buying your own O-rings.

Are people supposed to be born with this knowledge? He's trying to change a yoke oring. For Pete's sake, is there a process more simple, aside from picking your nose? Frankly, I would trust someone who was self reliant enough to at least change their own o-rings more than someone afraid of touching their regs. I rebuilt my regs with a rebuild kit and a bootleg manual. No training, no tech to show me what to do. Last time I checked, I was still breathing. And my regs breathe better than any rental I've had the misfortune to stick in my mouth.

Air oil is an excellent place to buy o rings. You might dig around in the DIY sections for more oring info. We had a few discussions last year, as I recall.

 

[captain]

Yoke O ring is 2-112, 1/2" ID, 11/16" OD, 3/32" C/S

O rings may be rocket science on rockets but not regulators.

 

[angryguy777]

I'll switch out the o-ring before I go on my liveaboard trip and if I have any problems I'm gonna take it to the shop I bought the regs from in NC. And of course, get some new o-rings. Thanks for the advice guys.

I also plan to learn more about my equipment. I know far too little about my regulators. Anyone happen to know of any oceanic equipment manuals online? I just thought it seemed so silly how I'm worried about unscrewing on something because it'll explode or suddenly shatter. Seems like the dive industry beats into everyone that unless you're licensed to repair something that you shouldn't even look at it wrong, even if you learn about it.

What a load of crap. Any of you that service your own stuff, where'd you learn?

-Zak

 

[WarmWaterDiver]

. . .

WarmWaterDiver has brought up another material that appears to be used. EPDM has two reasons for existing as an o-ring material -

1. It has great UV light resistance, so would be good anywhere that an o-ring could be exposed to sun light.

2. It can be made in nice colors. Nothing to do with performance, just looks cool.

Compared to Viton, it is not more resistent to 02 and has several other attributes that make it a bad choice for a high pressure O-ring, but it looks cool - never underestimate the importance of that. Nice choice for a Quick Disconnect o-ring that could lay out in the sun, but it is softer, far to elastic (easier to extrude under pressure) and tends to vary in production. Did I mention that it can be made in nice colors?

I guess I didn't make it clear enough that the purple EPDM O-ring I mentioned that extruded was on the inside of the yoke assembly, not exposed to sunlight / UV - just airport X-rays. A second such O-ring that goes on the outside of the DIN fitting, also purple, did not fail. It was exposed to the same airport X-rays as well as ambient light whenever the first stage cap is off.

I've been informed by our tech instructor that a number of the manufacturers are now using EPDM as an alternative to Viton, but only the batches with purple coloration seem to have had a problematic history in this service that he knows of. This is possibly due to variation in production as you mention - evidently the purple ones were the first EPDM batch used by Aqua Lung and Sherwood in lieu of viton.

I've certainly used EPDM as an alternative to teflon and viton in industrial services (like pump seal kits, not exposed to sunlight / UV) with success in certain applications - but I wasn't using them for O2 service, more for aggressive liquids like gas treating amines.

 

[kb2ehj]

Thanks Captain for the response.

Yoke O ring is 2-112, 1/2" ID, 11/16" OD, 3/32" C/S

O rings may be rocket science on rockets but not regulators.

 

[kb2ehj]

I small suggestion -Never, never buy something that your life may depend on at the suggest of someone on a forum.

Discussion is great, but if you have to ask what size is needed, you are most likely not a candidate for buying your own O-rings.

If the following link makes perfect sense to you, then you have more than enough skill to make your own decision:

*************
So stop make suggestions about the make up of o-rings.

I asked captain because I don't have access to a micrometer.

 

[oxyhacker]

Where are you getting your info? According to Parker, EPDM is a almost as good or equal to viton for O2 resistance, equal for weather resistance, and better in most mechanical properties like abrasion and tear resistance which is where viton really falls down. And better with cold. Several Parker reps have told me never recommend viton when they can avoid it, because they have so much trouble with it. About all EPDM is really bad at is oil resistance - but then you really shouldn't be using oil in your regulator.

As far as color, just about any O-ring can be made in any color you like. This is not a unique feature to EPDM. Scubapro used to use nitrile O-rings color coded to the location, and most of us have seen black, brown, red and green viton.

Since most reg manufacturers have gone over to EPDM O-rings as nitrox becomes commonplace, one assumes they must have some reasons.

1. It has great UV light resistance, so would be good anywhere that an o-ring could be exposed to sun light.

2. It can be made in nice colors. Nothing to do with performance, just looks cool.

Compared to Viton, it is not more resistent to 02 and has several other attributes that make it a bad choice for a high pressure O-ring, but it looks cool - never underestimate the importance of that. Nice choice for a Quick Disconnect o-ring that could lay out in the sun, but it is softer, far to elastic (easier to extrude under pressure) and tends to vary in production. Did I mention that it can be made in nice colors?

 

[RPanick]

The biggest issue with doing working on your own regs is getting the service kit, many of the manufacturers will only sell them to authorized dealers with trained service techs. Having sat through one of the training sessions it wasn't very hard to work on, but there are some things you do need to know about. Fortunately most were covered in the manual.

Before you take anything apart understand you may need a few special tools, and a gauge for measuring the pressure on the LP side.

When you take it apart you also need to be very careful about the order that things come apart and go back together.

With my LDS, when you get to DM/AI level they start teaching you how to a lot of this stuff, and will let you get training when it comes around. With two sets of eyes going through it, you can make sure the service tech replaces the parts he/she is supposed to replace. Rather than just looking at it.

I learned this the hard way, my HP seat in my reg had a problem. Likely the seat was worn or something got in it. The LP side was putting out over 300 PSI, which of course caused a free flow. Ruined a dive because of it. The tech told me they don't replace those unless there is a problem. I know better now.

 

[Creed]

What a load of crap. Any of you that service your own stuff, where'd you learn?

-Zak

The rebuild manual and common sense. You might want to start with either the airspeedpress book(http://www.airspeedpress.com/newregbook.html) or the Peter Built book(http://www.scubatools.com/RegSavvy.html). Parts availability depends on the make and model of your reg.
I would suggest starting with something easy to rebuild, like a Conshelf. You can pick one up from ebay for less than $50(like this one: http://cgi.ebay.com/SCUBA-U-S-DIVER...ryZ16056QQssPageNameZWDVWQQrdZ1QQcmdZViewItem), you can snag a rebuild kit off of ebay(or www.vintagedoublehose.com, or send me a private message), and you can get the manual from Aqualung(http://www.aqualung.com/military/PD...Manuals/Conshelf14 Repair Manual with DIN.pdf).