Tighten Your Nuts

grahamsp · 3rd January 2007, 02:45

Was stripping my Evo's scrubber down after today's dive when, to my great surprise and without any warning at all, the LP oxygen feed line to the solenoid blew out. Thankfully, the cylinder valve was shut so it was no big deal. More a pop than a bang.

On inspection, it seemed that the finger nut that holds the o-ring fitted bayonet connection in place had come undone allowing the connector to blow out. Refitting it was the work of only a few seconds as there was no fault with the hardware.

Lessons (re)learnt:

Be prepared. Thankfully the connector didn't blow underwater but if it had, it would have been an interesting few seconds getting on top of the problem. And whilst I am pretty confident I would have got it sorted (unexplained massive gas loss is one of the scenarios I have a pre-planned response for), I do wonder how I would actually have handled it at 45 metres (or even worse, at 74 metres on my previous dive).

Check every connector prior to every dive. Because the scrubber lid connectors are never disconnected at any time and because they were always as tight as a duck's arse whenever I did check, I had fallen into the habit of only checking them periodically (though all other connectors are checked pre-dive). Big mistake. In this case, the lid connectors were last checked when I got back from a liveaboard trip about two months ago since when I've done only 3 dives. In that time, the solenoid connector has either worked its way loose or I didn't check it properly in the first place. Either way, it and the rest of the scrubber lid connectors will be checked carefully from now on.

There you have it. Not a big deal but that was the product of luck not good practice. So for all you Evo (and Inspo?) owners out there, keep those scrubber head nuts tight.

Graham

***caveseeker7*** · 3rd January 2007, 08:59

Geez Graham, with that title my nuts tightened all by themselves.

Good advice though.

grahamsp · 3rd January 2007, 11:47

Quote: (Originally Posted by caveseeker7)

Geez Graham, with that title my nuts tightened all by themselves.

Good advice though.

So did mine when I thought about what might have happened!

Graham

***Decodiver*** · 3rd January 2007, 16:03

I always undo the O2 feed and the ADV feed on the inspo after every dive.

I lightly grease the threads then reassemble.

As these are metal to metal fixtures, if you do not disassemble and grease them regularly you may find them rock solid one day.

Cheers,

Dave Cooper.

grahamsp · 4th January 2007, 02:31

Quote: (Originally Posted by Decodiver)

I always undo the O2 feed and the ADV feed on the inspo after every dive.

I lightly grease the threads then reassemble.

As these are metal to metal fixtures, if you do not disassemble and grease them regularly you may find them rock solid one day.

Cheers,

Dave Cooper.

Noted. Thanks.

G

rdmmdr · 4th January 2007, 06:43

Taking them apart after every dive sounds a little anal to me. but hey what ever works for you. Find an airplne friend and get some torque seal from him for the fittings. Or just use the grilfriends nail polish, make sure it is a match to the wife's, just incase she sees it.

rick

***Beanie*** · 4th January 2007, 08:45

Quote: (Originally Posted by rdmmdr)

Taking them apart after every dive sounds a little anal to me. but hey what ever works for you. Find an airplne friend and get some torque seal from him for the fittings. Or just use the grilfriends nail polish, make sure it is a match to the wife's, just incase she sees it.

rick

you have to take the solinoid hose off every strip down to take the head off

UKSteve · 4th January 2007, 09:14

I'm starting to wonder exactly what came loose? Was it the knurled head connection between the head and the LP O2 hose or did the whole fitting come loose from the head?

Hmm. having read that again it doesn't come across very clear....any chance of a pic to identify exactly what separated from what?

Dave (Decodiver) mentioned the similar connection on the end of the hose to the APD ADV. While I don't always remove the connection to the ADV I do always check it is tight now after discovering, by chance, it was very loose (have added it as a line on my plasticised pre-dive checklist).

The other one to check is the spiggots for manual O2 and dil - discovered one of these loose and backing quietly out of the plastic body.

Steve

decoweenie · 4th January 2007, 09:22

Quote: (Originally Posted by UKSteve)

Was it the knurled head connection between the head and the LP O2 hose...

It has to be this since it only took a few seconds to fix.

This is similar to the same connection for OC 2ndary reg. It is only hand-tight so need to be checked before every dive.

UKSteve · 4th January 2007, 09:33

Quote: (Originally Posted by grahamsp)

In this case, the lid connectors were last checked when I got back from a liveaboard trip about two months ago since when I've done only 3 dives. In that time, the solenoid connector has either worked its way loose or I didn't check it properly in the first place. Either way, it and the rest of the scrubber lid connectors will be checked carefully from now on.

Quote: (Originally Posted by decoweenie)

It has to be this since it only took a few seconds to fix.

This is similar to the same connection for OC 2ndary reg. It is only hand-tight so need to be checked before every dive.

Phi,

Not convinced...unless Graham leaves the head connected to the O2 IP hose at all times when changing out the scrubber etc. That connection is released every time I remove the scrubber from the case.

Steve

3rd January 2007, 02:45	#1 (permalink)
grahamsp New Member Current Rebreather/s: Evolution Other Rebreather/s: Join Date: Jun 2005 Location: Sydney, Australia Posts: 113	Tighten Your Nuts Was stripping my Evo's scrubber down after today's dive when, to my great surprise and without any warning at all, the LP oxygen feed line to the solenoid blew out. Thankfully, the cylinder valve was shut so it was no big deal. More a pop than a bang. On inspection, it seemed that the finger nut that holds the o-ring fitted bayonet connection in place had come undone allowing the connector to blow out. Refitting it was the work of only a few seconds as there was no fault with the hardware. Lessons (re)learnt: Be prepared. Thankfully the connector didn't blow underwater but if it had, it would have been an interesting few seconds getting on top of the problem. And whilst I am pretty confident I would have got it sorted (unexplained massive gas loss is one of the scenarios I have a pre-planned response for), I do wonder how I would actually have handled it at 45 metres (or even worse, at 74 metres on my previous dive). Check every connector prior to every dive. Because the scrubber lid connectors are never disconnected at any time and because they were always as tight as a duck's arse whenever I did check, I had fallen into the habit of only checking them periodically (though all other connectors are checked pre-dive). Big mistake. In this case, the lid connectors were last checked when I got back from a liveaboard trip about two months ago since when I've done only 3 dives. In that time, the solenoid connector has either worked its way loose or I didn't check it properly in the first place. Either way, it and the rest of the scrubber lid connectors will be checked carefully from now on. There you have it. Not a big deal but that was the product of luck not good practice. So for all you Evo (and Inspo?) owners out there, keep those scrubber head nuts tight. Graham
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3rd January 2007, 08:59	#2 (permalink)
*caveseeker7* Who loves ya, baby Current Rebreather/s: Sport Kiss Other Rebreather/s: Prism Topaz Join Date: Jan 2005 Location: Too far from Neverland Posts: 5,498	Re: Tighten Your Nuts Geez Graham, with that title my nuts tightened all by themselves. Good advice though. __________________ Cheers Stefan "Political Correctness is a doctrine, fostered by a delusional, illogical minority, and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.!"
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3rd January 2007, 11:47	#3 (permalink)
grahamsp New Member Current Rebreather/s: Evolution Other Rebreather/s: Join Date: Jun 2005 Location: Sydney, Australia Posts: 113	Re: Tighten Your Nuts Quote: (Originally Posted by caveseeker7) Geez Graham, with that title my nuts tightened all by themselves. Good advice though. So did mine when I thought about what might have happened! Graham
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3rd January 2007, 16:03	#4 (permalink)
*Decodiver* Administrator Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Jan 2005 Location: Geneva Posts: 2,197	Re: Tighten Your Nuts I always undo the O2 feed and the ADV feed on the inspo after every dive. I lightly grease the threads then reassemble. As these are metal to metal fixtures, if you do not disassemble and grease them regularly you may find them rock solid one day. Cheers, Dave Cooper. __________________ CCR/OC Trimix Instructor Trainer CCR Training to Mixed Gas in Switzerland, France, UK & Germany on Megalodon/COPIS-Megalodon/KISS/Sport KISS/Ouroboros/rEvo/Inspiration/Evolution/Sentinel www.zerogravitydiving.com Rebreather World Terms & Conditions
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4th January 2007, 02:31	#5 (permalink)
grahamsp New Member Current Rebreather/s: Evolution Other Rebreather/s: Join Date: Jun 2005 Location: Sydney, Australia Posts: 113	Re: Tighten Your Nuts Quote: (Originally Posted by Decodiver) I always undo the O2 feed and the ADV feed on the inspo after every dive. I lightly grease the threads then reassemble. As these are metal to metal fixtures, if you do not disassemble and grease them regularly you may find them rock solid one day. Cheers, Dave Cooper. Noted. Thanks. G
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4th January 2007, 06:43	#6 (permalink)
rdmmdr designer of death Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Mar 2006 Location: kerman,california Posts: 372	Re: Tighten Your Nuts Taking them apart after every dive sounds a little anal to me. but hey what ever works for you. Find an airplne friend and get some torque seal from him for the fittings. Or just use the grilfriends nail polish, make sure it is a match to the wife's, just incase she sees it. rick
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4th January 2007, 08:45	#7 (permalink)
*Beanie* give a man an inch....... Current Rebreather/s: Inspiration Classic Other Rebreather/s: Inspiration Vision Join Date: Jan 2005 Location: In da house! yeah baby! Posts: 3,248	Re: Tighten Your Nuts Quote: (Originally Posted by rdmmdr) Taking them apart after every dive sounds a little anal to me. but hey what ever works for you. Find an airplne friend and get some torque seal from him for the fittings. Or just use the grilfriends nail polish, make sure it is a match to the wife's, just incase she sees it. rick you have to take the solinoid hose off every strip down to take the head off __________________ Beanie Gallery Admin & Library Assistant. www.outlawdivers.org.uk www.beandiving.co.uk www.beanengineering.co.uk 0871 242 7808
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4th January 2007, 09:14	#8 (permalink)
UKSteve Steve Collard Current Rebreather/s: Inspiration Vision Other Rebreather/s: Join Date: Jul 2005 Location: Weymouth, UK Posts: 606	Re: Tighten Your Nuts I'm starting to wonder exactly what came loose? Was it the knurled head connection between the head and the LP O2 hose or did the whole fitting come loose from the head? Hmm. having read that again it doesn't come across very clear....any chance of a pic to identify exactly what separated from what? Dave (Decodiver) mentioned the similar connection on the end of the hose to the APD ADV. While I don't always remove the connection to the ADV I do always check it is tight now after discovering, by chance, it was very loose (have added it as a line on my plasticised pre-dive checklist). The other one to check is the spiggots for manual O2 and dil - discovered one of these loose and backing quietly out of the plastic body. Steve
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4th January 2007, 09:22	#9 (permalink)
decoweenie Crash Test Dummy Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Feb 2005 Location: Cairo Posts: 5,510	Re: Tighten Your Nuts Quote: (Originally Posted by UKSteve) Was it the knurled head connection between the head and the LP O2 hose... It has to be this since it only took a few seconds to fix. This is similar to the same connection for OC 2ndary reg. It is only hand-tight so need to be checked before every dive. __________________ "...after a while you get bored offering advice to a bull that like to keep butting the fence with its head rather than walking through the open gate..." - Rebreather World PM
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4th January 2007, 09:33	#10 (permalink)
UKSteve Steve Collard Current Rebreather/s: Inspiration Vision Other Rebreather/s: Join Date: Jul 2005 Location: Weymouth, UK Posts: 606	Re: Tighten Your Nuts Quote: (Originally Posted by grahamsp) In this case, the lid connectors were last checked when I got back from a liveaboard trip about two months ago since when I've done only 3 dives. In that time, the solenoid connector has either worked its way loose or I didn't check it properly in the first place. Either way, it and the rest of the scrubber lid connectors will be checked carefully from now on. Quote: (Originally Posted by decoweenie) It has to be this since it only took a few seconds to fix. This is similar to the same connection for OC 2ndary reg. It is only hand-tight so need to be checked before every dive. Phi, Not convinced...unless Graham leaves the head connected to the O2 IP hose at all times when changing out the scrubber etc. That connection is released every time I remove the scrubber from the case. Steve
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