Wanting to Service My Own Regs

[windapp]

In a year when my regs need servicing, I would like to service my own. I have done a little research on the operation and service procedures for my MK-10/R109, and I have gotten to the point where I want to invest in a good book and some tools. I will be posting later with a picture of my US Divers octo that I can't figure out what model it is.

I can find lots of annual service kits online, but I was interested in where does one obtain parts that are not part of the kit, especially O-Rings? What sorts of non-kit parts would I most likely need to have as spares so that I am not waiting around to get them by mail?

I also noticed that the high pressure seat o-ring for the MK-10 is no longer part of the service kit (100-500-45). Anybody know the reason for this?

 

[redacted]

The HP seat o-ring has been replaced by a flat washer which is in the kit.

Lots of sources for o-rings. This is just an example: O-Ring Specialists, Viton® O-Rings, Kalrez® O-Rings, Buna O-Rings, O-Ring Design and Material Selection Guide, Buy O-Rings Online

With a Mk10 (or any other BP 1st) it is not a bad idea to pick up a spare piston if the opportunity arises. And the 109 will need a duro poppet if it does not already have one.

 

[windapp]

Thanks for the advise. I figured out what my octo is. It's a Conshelf 21. It looks like there are kits to be found, and repair manuals available.

If I have the early version MK-10 with the really small ambient holes, I assume that it must be packed with silicone grease as the holes are not large enough for proper rinsing and water flow. Is this correct? Is there a nitrox-compatible equivalent for this process?

 

[redacted]

I don't rinse regulator. I soak them for 6 to 8 hours and the size of the ambient chamber holes is not a problem. But dipping them and allowing them to empty will accelerate the cleaning of the ambient chamber. It will still take a long soak to pull the salt out of the ambient chamber threads and the din/yoke retainer threads as well as other unprotected threads. I have heard of folks drilling out those smaller holes.

I use Mk5/7/10s with nitrox with just the standard parts.

 

[Bubbletrubble]

Thanks for the advise. I figured out what my octo is. It's a Conshelf 21. It looks like there are kits to be found, and repair manuals available.

You'll probably want to stock up on the Conshelf 21 kits if you're going to be DIY servicing.
Northeast Scuba Supply currently sells the appropriate overhaul kit for the Conshelf 21 (#900013) for $6.49 each.
The kit includes the locknut and the LP seat, which would be harder to source from 3rd party companies than the o-rings.

 

[windapp]

awap...By "with just the standard parts", do you use silcone greese or crystolube? Obviously you have serviced them yourself. Any sign of problems from the nitrox?

Oh yeah...and the service parts. Do they keep on the shelf over several years?

I had a look through the Conshelf 14 manual (I understand the inner workings are the same). It seems to be a lot more thorough manual than the scuba-pro manuals.

 

[Bubbletrubble]

Oh yeah...and the service parts. Do they keep on the shelf over several years?

BunaN o-rings should last several years.
EPDM or Viton o-rings have an indefinite shelf-life.
Depending on the manufacturer, the LP seats can be made of different materials.
I think awap punches his own LP seats from a sheet of EPDM. (Is that correct, awap?)

 

[herman]

BunaN o-rings should last several years.
EPDM or Viton o-rings have an indefinite shelf-life.
Depending on the manufacturer, the LP seats can be made of different materials.
I think awap punches his own LP seats from a sheet of EPDM. (Is that correct, awap?)

I was doing some searching on oring life a week or 2 back. The standard I found (an ANSI standard for aircraft) listed the shelf life of properly stored (cool/dark/proper package) BurnaN orings at 15 years, I think viton was the same but in any case none were less than 15 years. Since this was shelf life and the oring could still be used in an aircraft I suspect it was very conservative.
The material for the LP seats was EDPM, 70 durometere if I remember correctly.

Nitrox is not a big deal as long as you are staying less than 40%/. Most use viton orings instead of BunaN (aka nitrile) but they are not really necessary. If you are ordering a bag of orings anyway the cost difference is maybe a few dollars per hundred. Same goes for Christolube vs. silicone, as long as you are staying in the rec nitrox level, silicone is fine and since I have large tubes of it, I am not going to spend a good bit of cash for unnecessary Christolube.

 

[Couv]

Hello Windapp,

You've gotten excellent advice already, so I'll just address a couple of things not covered.

In a year when my regs need servicing, I would like to service my own.

Regulators do not necessarily need to be serviced annually. Several of us put our heads together and produced this checklist to help you decide when it's necessary.

http://www.scubaboard.com/forums/regulators/346813-regulator-inspection-checklist-rev-7-a.html

....I have gotten to the point where I want to invest in a good book and some tools.

Both service manuals usually discussed here are great; Vance Harlow's "SCUBA Regulator Maintenance and Repair"
SCUBA REGULATOR MAINTENANCE AND REPAIR by Vance Harlow

and the Scuba Tools book, "Regulator Savvy" Scuba Tools are well worth the money.I own both and recommend getting one of each; but if you're dead set on getting only one, then Vance's is a little more suitable for the DIY guy while the ScubaTools book is more suitable for the shop worker. ScubaTools has some pretty handy tools too, so if you do order from there, pay a few extra bucks and get the bullets, spanners, and regulator specific tools that you'll need with your first order and save on shipping. Get a few old regulators like the ones you'll be servicing from eBay or Craig's list and practice. After just one or two seasons of servicing your own gear, you'll have recovered your investment. While you're waiting for your books to come in, page through a few of the manuals found here:

Regulator manuals Regulator manuals & http://www.frogkick.dk/manuals/

If I have the early version MK-10 with the really small ambient holes, I assume that it must be packed with silicone grease as the holes are not large enough for proper rinsing and water flow. Is this correct? ?

I see you're up in Canada, so that may be a good idea. Packing the ambient chamber with grease is for environmental purposes. If you'll be diving in very cold or very silty water that would be the reason to pack the chamber. It would not hurt to pack it for typical diving, it's just not necessary for cleaning purposes...as Awap said, SOAK not rinse.

Is there a Nitrox-compatible equivalent for this process ?

Answered already, but to reiterate. All regulators are Nitrox ready up to 40% Higher than that special cleaning and materials should be used.

Good luck,

Couv

 

[redacted]

awap...By "with just the standard parts", do you use silcone greese or crystolube? Obviously you have serviced them yourself. Any sign of problems from the nitrox?

Oh yeah...and the service parts. Do they keep on the shelf over several years?

I had a look through the Conshelf 14 manual (I understand the inner workings are the same). It seems to be a lot more thorough manual than the scuba-pro manuals.

I use Tribolube - Christolube competitor. I have a fair stock of some very old parts including o-rings and LP seats that are pushing 20 and HP seats that appear to be even older. I have never had any that deteriorated beyond usable. Only catch is some designs will change/evolve and that may reduce the usability of some older parts. Store soft parts in airtigh container in cool and dry location.

And yes, I make my own hockey puck style LP seats (for Scubapro 2nds) .