scba tanks down

bigHUN

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Jan 16, 2020
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I had very difficult work schedules the entire summer, last time I visited my gun club BR back somewhere in June. These two 14 liter scba tanks were sitting the entire time fully top up.
Somewhere in mid August I wanted to use the right tank (with sticker on it), the seal under the valve knob broke. Fine, I put it aside and used the left tank couple of times. Today I wanted to refill my Leshiy2 and this valve knob seal broke as well. So ended up with two fully charged tanks now, and speculating there is no other way around but degass. Measured the pressure and with a leak there is still about 260 bars in each, or perhaps more.
I still have one 9 liter Acecare as a spare for case of emergency :) .

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The tank on the left side I replaced the scba to DIN valve somewhere in 2019-20, and I still have one valve BNIB.

20231105_180105.jpg


I am just looking at these valves in a bag, I don't see a way how could I open them to re-seal, hypothetically if I could find orings for these...
Tinkering now to order two new - better quality valves, or just buy one new 9 liter Acecare again ???
With a single 9 liter tank a bench rest tethering is a little bit on the modest side, but two tanks may put me back in the game with full capacity.
 
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I had very difficult work schedules the entire summer, last time I visited my gun club BR back somewhere in June. These two 14 liter scba tanks were sitting the entire time fully top up.
Somewhere in mid August I wanted to use the right tank (with sticker on it), the seal under the valve knob broke. Fine, I put it aside and used the left tank couple of times. Today I wanted to refill my Leshiy2 and this valve knob seal broke as well. So ended up with two fully charged tanks now, and speculating there is no other way around but degass. Measured the pressure and with a leak there is still about 260 bars in each, or perhaps more.
I still have one 9 liter Acecare as a spare for case of emergency :) .

View attachment 403467

The tank on the left side I replaced the scba to DIN valve somewhere in 2019-20, and I still have one valve BNIB.

View attachment 403474

I am just looking at these valves in a bag, I don't see a way how could I open them to re-seal, hypothetically if I could find orings for these...
Tinkering now to order two new - better quality valves, or just buy one new 9 liter Acecare again ???
With a single 9 liter tank a bench rest tethering is a little bit on the modest side, but two tanks may put me back in the game with full capacity.
Yes you have to degass to reseal. Mechanically it should be a simple opreation. McmasterCarr will have orings. You can find cheaper elsewhere. This is high pressure and you should be reasonably familiar. Otherwise take to a scuba shop. Might be cheaper to buy new valve than pay hourly rate for service.
 
I am usually a diy guy and I am ready to move the rocks to find my parts. Both of these valves in above picture leaks on orings on the shaft probably as I circled below, the valve on-off function is OK.

valve orings.JPG


The only problem with the old valve left side in picture I don't see any access holes the knob must be pressed in and snapped in place, so that one is busted and will throw in garbage.
The Din valve (on the right) I can see a nut and shall be able to remove the plastic knob, but I will definitely degas first. That broken valve will be my learning curve when removed.
I will start degassing in the morning in garage when nobody at home not to bother family with the hissss, will take probably a whole day. I don't want to empty the tank too fast because of thermal shock.
 
I am usually a diy guy and I am ready to move the rocks to find my parts. Both of these valves in above picture leaks on orings on the shaft probably as I circled below, the valve on-off function is OK.

View attachment 403538

The only problem with the old valve left side in picture I don't see any access holes the knob must be pressed in and snapped in place, so that one is busted and will throw in garbage.
The Din valve (on the right) I can see a nut and shall be able to remove the plastic knob, but I will definitely degas first. That broken valve will be my learning curve when removed.
I will start degassing in the morning in garage when nobody at home not to bother family with the hissss, will take probably a whole day. I don't want to empty the tank too fast because of thermal shock.
My bad. Didn't pay attention to who was asking the question :). The red knob on right is likely installed in similar fashion. See if there is a sticker or plug covering the nut or bolt. SCBA valves often have a ratchet type mechanism to keep them from being closed accidentally ( don't want to turn off breathing air by accident)... If you do break the knob, you can probably make any type of knob for your purposes afterward.
 
MY personal preference is to use original Scott SCBA valves. Firefighter lives depend on them & they are less likely to fail & less parts than aftermarket valves.
I base this on 30+ years in fire equipment field. OEM SCBA valves are robust & can be found cheaply if replacement is needed.
 
This is interesting...
How this valve could possibly not leak earlier?

where is the oring.JPG


If I am not mistaking there suppose to be an oring on that brass shaft ??? Did it disintegrated and turned into that black tar/grease?
The other thing the larger oring on that nut at right was squeezed out almost half ... this almost four years of active gun range use.
Replacing orings looks pretty straight forward to me, because ordering from aliexpress lately is a pain to wait.
 
No other way around, I toke a spare valve apart to see what happened here.
Unbelievable, the oring disintegrated, turned into a paste...

View attachment 404645

At least I have now samples to measure and order a full set
Enclosed space like this Urethane 90 durometer o-ring will last best. (urethane doesn't like ozone and will disintegrate but ozone won't get into this space).
 
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I have a question I found an eBay tank https://www.ebay.com/itm/233621697771 does anyone have any experience with these Chinese made tanks
Yes I have one of the 9L tanks. Purchased about a year ago. It is not DOT marked but thats ok as i fill my own. Been holding pressure without issues and from the outside seems as sturdy as the scott tanks i have.
 
Yes, I have also one of those Acecare 9 Liter, keeping it filled for case of emergencies, as it happened that I emptied the two 14 Liter scba tanks to redress with new orings. 9 Liter is a nice size as a "second" tank, I don't think as a single would be enough air for my style of shooting.
Where did you find/get 14L tanks from? I'm intrigued.
 
Where did you find/get 14L tanks from? I'm intrigued.
Somewhere back in 2018 maybe I ran into one government auction sale when they were replacing the entire fire station equipment (Toronto). I called quickly couple of friends and we bought the entire rack of bottles+masks+backpacks, I think we paid somewhere around $1800 CAD back then for a full rack. I kept four bottles for myself but gifted out two and I used two of the tanks all these time.
I remember a guy (some farmer boy) bought that day a "decommissioned" fire truck for peanuts.
Not sure for USA but in Canada the government is updating these properties like every 10 years. We have some websites for these auction sales but have not tracked ever since.

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