O-ring size for inside of DIN insert

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elgoog

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Location
San Francisco Bay area
# of dives
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Hello -

I had a slight leak in my left post yesterday and narrowed it down to the 1st stage. The screw in DIN insert was slightly loose. When I removed it completely to check on it, I noticed that the o-ring just above the inside threads was extruded due to the reg being pressurized with the insert not fully tightened down.

Could you let me know what o-ring size I should get to replace this one? This is not the normal DIN o-ring on the outside of the 1st stage - the one I'm asking about is not visible when the reg is in dive ready state.

I've attached a photo of the part I'm referring to.
IMG_20170903_220512.jpg

Thanks in advance,
elgoog
 
@elgoog - when I opened this post - I had assumed you were referring to the DIN insert in a Pro Valve. But that is not the part you have pictured. Is this a part from your first stage - and if so - what manufacturer and model of first stage?
 
Is this a part from your first stage - and if so - what manufacturer and model of first stage?
Yes, this is a component in the 1st stage reg, not the valve insert. It is a Deep6 1st stage, I didn't specify that or the model as I put this post in their sub-forum and they only make one model.
 
Assuming we are talking about the oring that seals between the din assembly and the first stage body - that is generally something that would get replaced during service.

I couldn't find a manual online for deep 6 - and that is not a manufacturer we service. However, Divegearexpress sells the 1st stage service kits for that 1st state - and I believe you would find the proper oring in that kit.

Service Parts Kits for Deep Six Regulators

I'd suggest that if you do the repair yourself - you find the proper torque setting for that DIN assembly and tighten it to the specified torque. It will help prevent that oring from extruding again before service.
 
Assuming we are talking about the oring that seals between the din assembly and the first stage body - that is generally something that would get replaced during service.
Yep, that's the one.

However, Divegearexpress sells the 1st stage service kits for that 1st state - and I believe you would find the proper oring in that kit.https://www.divegearexpress.com/service-parts-kits-for-deep-six-regulators
https://www.divegearexpress.com/service-parts-kits-for-deep-six-regulators
I do have a 1st stage service kit that came with the reg purchase so, I could, in theory, use the o-ring from that in a pinch, but I'd rather leave that kit intact for when I send it in for service.

I'd suggest that if you do the repair yourself - you find the proper torque setting for that DIN assembly and tighten it to the specified torque. It will help prevent that oring from extruding again before service.
I don't plan on servicing my regs at the moment but I have removed that DIN assembly before to swap it out. My original reg purchase came with the "wrong" DIN assembly that was not in spec. Deep6 sent me the correct one and I swapped them out - I tightened it by feel only at that time. I've used these regs for about 30 dives so far and this is the 1st time I noticed that it had loosend enough to cause a leak and extrude the o-ring.

Couple of questions for @Deep Six in addition to the o-ring size
- Is the loosening of the insert expected with normal use? I can totally see how it would loosen while putting the regs on and off the valves and it's trivial to check tightness when I assemble my rig. I don't usually do this as Deep6 are the only regs I have that have the removable insert. AFAIK, Apeks DST 1st stages don't have this.
- Is tightening the DIN insert by feel sufficient? If not, what's the correct torque setting?
 
That's a static O-ring. You can use the same one for years as long as it's not damaged.
 
This is what it looked like when I first took the DIN insert out.
IMG_20170904_104321.jpg

Just for funsies, I gently pulled apart the bits of rubber that are sticking out to make the o-ring smooth again and put it back in the reg. No leaks now. I've got it hooked up to a tank to see if it leaks over a period of a few hours.

Even if it doesn't, I'd want to replace the o-ring just for the peace of mind.
 
Might be a -011 or -012. Compare with your LP and HP port o-rings.

Whatever fits without being too large or small would probably work, even if not the exact correct size
 
Might be a -011 or -012. Compare with your LP and HP port o-rings.
I've got a bunch of those - I'll go through my o-ring colle ction and find one close to the original.

Whatever fits without being too large or small would probably work, even if not the exact correct size
Yeah, I'm realizing that putting in the exact size isn't as critical here. The reg with the picked clean o-ring has held pressure perfectly for over an hour.
 
What I was getting at is using the one in the overhaul kit would be fine.....for years.
But, as stated it is likely an 011, or 012, pretty standard size.
 
https://www.shearwater.com/products/teric/

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