Service Life Of Diaphragms In 2nd Stages -- Conshelf And Others

[herman]

If you are going to rebuild the Conshelf 1st stages I would highly recommend getting the high pressure installation tool, it works on the Conshelf, original Titan, and several similar regs. It can be done without it but parts have a nasty habit of flying every where without it. I believe Herman on this board sells them inexpensivly. I tried once with out it and said hell no and got the tool.

The HP internals are are a huge pain to get back in without one. Drop ,me a PM for details.

 

[Tug]

If you are going to rebuild the Conshelf 1st stages I would highly recommend getting the high pressure installation tool, it works on the Conshelf, original Titan, and several similar regs. It can be done without it but parts have a nasty habit of flying every where without it. I believe Herman on this board sells them inexpensivly. I tried once with out it and said hell no and got the tool.

I'll second this! The tool that Herman makes has made rebuilds much easier for myself and some of my friends. His tool is highly recommended!

 

[2airishuman]

The old rubber diaphrams would wear out, the silicone ones will last ... who knows.. I have a bunch of spares and don't remember exchanging one for 15 yrs now. Just gently stretch and hold up to the sun and inspect for a holes..

Incidentally, do you know what to do if one rips while diving and you don't want to or can't switch to an alternate?

I've never really thought about it, but my first response would be to feather the purge button.

 

[The Chairman]

I've had to replace only one diaphragm and that was due to a diver trying to service his own reg. Somehow, he put a small screw driver through it trying to undo the cover.

 

[guruboy]

The old rubber diaphrams would wear out, the silicone ones will last ... who knows.. I have a bunch of spares and don't remember exchanging one for 15 yrs now. Just gently stretch and hold up to the sun and inspect for a holes..

Incidentally, do you know what to do if one rips while diving and you don't want to or can't switch to an alternate?

The guy with a bunch of spare diaphragms gets banned just before I start looking for one. Go figure...

 

[oldschoolto]

What did dumpsterdiver do now ???

Jim...

 

[USdiver1]

Personally, I would replace rubber with silicone. That should last about 30 years. In some of my older AMF/Voit second stages, the change from the plasti-koted canvas to a Mares silicone diaphragm (MR-12 to Abyss) produced a noticeable improvement in perceived cracking effort and ease of breathing. I have several Connies with diaphragms exceeding 30 years of use. They just don't wear out.

 

[guruboy]

If you know where I can get some of those gray silicone ones (like in OP's pic), I'm all ears..

I have a black that feels like silicone but looked like this when I took apart the second stage. It either was defective to begin with or deformed after being improperly installed for around 15 years.

 

[Couv]

Trident may make a replacement. If you download the catalog don't find out the hard way that the index is near the back. :-(

Edit: I just ran across this thread: Conshelf Parts

 

[guruboy]

Thanks, couv. Found that earlier too.

I think that one is rubber though, not sure. I have some ordered, will report back when I receive them.