CO2 cartridges - best before ? - and lifejacket maintenance

sarabande

sarabande

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Going through my LJs checking them, according to the book. 8 of the units.

I have one of the digital scales that I have checked with a known mass of 100gm, so am reasonably confident it is not telling porkies.

All the cartridges are the "38g" type, stamped with minimum gross weights of between 150 and 165g to 1 decimal place.

6 of them weigh in at closely above their specified gross weight , but two notch up 243 and 256g. Is it likely that these are not fit for service ? I don't understand why they are so overweight.

I should add that manufacturing dates range between 2016 and 2009 for the 'good' ones, so I am inclined to buy four new cylinders for my 'best' LJs, and use the four newest spares for the plainest LJs (i.e. those without hoods and lights, and which are least likely to be used au large.)

Crew numbers very rarely exceed four BTW, and I'd expect competent guest crew to bring their own LJ. I know I would.

I am happy to test fire the overweight ones and report back if people think it would help. Bit of fun for a gloomy winter :)
 
I do my own LJ servicing ... and weigh cylinders ....

If the cylinders and gear shows no signs of wear or corrosion - there is no reason to discard any part if it meets the specs.

As to your overweight cylinders ... that is very strange as that is a near 2x increase ... I would be highly suspicious of their origin and intended use ...
 
sarabande said:
Going through my LJs checking them, according to the book. 8 of the units.

I have one of the digital scales that I have checked with a known mass of 100gm, so am reasonably confident it is not telling porkies.

All the cartridges are the "38g" type, stamped with minimum gross weights of between 150 and 165g to 1 decimal place.

6 of them weigh in at closely above their specified gross weight , but two notch up 243 and 256g. Is it likely that these are not fit for service ? I don't understand why they are so overweight...…
Click to expand...

Have you accidentally used an "add" function on the scales? Your test weight plus a typical cylinder would give the figures quoted.
 
This is a good post as it reminded me to check my LJ's ..... all three good but one with cylinder at 101gr ... noted the seal was punctured.

Strange as LJ was still folded and velcro in place ... so could not have been an accidental tag pull ....

Need check the trigger and find my spare Co2 bottles !!

LJ's are now inflated and will stay till tomorrow ...
 
Hope you checked at the start that all the jackets are of the same capacity (buoyancy).
I would also be concerned if any cylinders showed such a large discrepancy to the stated weight, as putting twice the quantity of gas into the jacket could make it pop if no pressure relief valve.
 
Strange.... as per the other comments relating to the two 'overweight' ones. Is OP sure that they are stamped 150 to 165 or was that assumed as the others all were?
We have our own digital mini ( drugs ?) scale on board, gives us a bit of confidence when we check LJs . If weight correct and appearance good we continue with them.
 
Very odd.
Assuming the cylinders really are interchangeable, I'd probably put one of the overweight cylinders in the oldest scruffiest LJ and try it.
I bin my LJs at around the recommended 10 yrs. The oldest one is used for coastal/racing/RIB/in harbour so gets scruffy.
Would you have weighed the cylinders last year? or before?

I do recall a tall story about someone trying to weigh a magnetised steel item on a scale with a steel base....
Other than that, they're mysteriously full of water or asphaltene....
 
I can't see any way a normal 38g cylinder can weigh twice its normal gross weight. Either there's something going on with the scales as Penberth3 suggests, or they're cylinders for 275 Newton LJs, but that would be obvious as they're a good bit bigger.

As far as I am aware, there's no best before date on the cylinders. Mine get a visual inspection (any significant rust or damage - fail), then I weigh them. If they're over the stamped on minimum gross weight, they go back in. I've condemned a few on a friend's jackets for rust, but never had one that's underweight. Likewise for the LJs; a careful visual inspection of everything and an inflation test, cartridge in date and not missing any green bits. If they pass, they're good to go. Mine are, from memory, 13 years old, but still good for another few years

Incidentally, I once tested some cartridges that were 5 years out of date. They all went off with a satisfying pop.
 
I have two from 1998 ..... perfect condition .... even cylinders weigh same as I mark on them weight when new ..... XM Quickfit

Third is from 2003 ..... perfect condition .... but cylinder was empty - replaced ..... Lazilas Crewsaver

I don't see any reason to bin them .....
 
sarabande said:
Going through my LJs checking them, according to the book. 8 of the units.

I have one of the digital scales that I have checked with a known mass of 100gm, so am reasonably confident it is not telling porkies.

All the cartridges are the "38g" type, stamped with minimum gross weights of between 150 and 165g to 1 decimal place.

6 of them weigh in at closely above their specified gross weight , but two notch up 243 and 256g. Is it likely that these are not fit for service ? I don't understand why they are so overweight.

I should add that manufacturing dates range between 2016 and 2009 for the 'good' ones, so I am inclined to buy four new cylinders for my 'best' LJs, and use the four newest spares for the plainest LJs (i.e. those without hoods and lights, and which are least likely to be used au large.)

Crew numbers very rarely exceed four BTW, and I'd expect competent guest crew to bring their own LJ. I know I would.

I am happy to test fire the overweight ones and report back if people think it would help. Bit of fun for a gloomy winter :)
Click to expand...
38 gm cylinders come in various sizes and weights so make sure you are reading the correct details from each individual cylinder.
I look after about 20 lifejackets and have never had a problem of an increase in weight. I weigh and log weight going into use and annually plus if a clip has been found missing .I would check all the details on the High weight bottles and confirm they have 38 gm as indicated content .
sarabande said:
Going through my LJs checking them, according to the book. 8 of the units.

I have one of the digital scales that I have checked with a known mass of 100gm, so am reasonably confident it is not telling porkies.

All the cartridges are the "38g" type, stamped with minimum gross weights of between 150 and 165g to 1 decimal place.

6 of them weigh in at closely above their specified gross weight , but two notch up 243 and 256g. Is it likely that these are not fit for service ? I don't understand why they are so overweight.

I should add that manufacturing dates range between 2016 and 2009 for the 'good' ones, so I am inclined to buy four new cylinders for my 'best' LJs, and use the four newest spares for the plainest LJs (i.e. those without hoods and lights, and which are least likely to be used au large.)

Crew numbers very rarely exceed four BTW, and I'd expect competent guest crew to bring their own LJ. I know I would.

I am happy to test fire the overweight ones and report back if people think it would help. Bit of fun for a gloomy winter :)
Click to expand...
If you do this then be sure to weigh before and after inflation and check against details on the cylinder . If there really is a difference then questions should be asked especially if marked as 38 gms
 
A new LJ costs about £50. So that's £5 a year.
The boat set of LJs is four, so £20 a year to have them within the recommended date, vs say a tenner a year if we dragged them out to 20 years.
So we could save maybe a tenner a year split between two co-owners.
In terms of the overall boat budgets, it's cheap.

I've seen enough 15 year old so-called waterproof stuff leak. Enough dodgy zips, broken plastic clips.

I think guests on the boat have a reasonable expectation of the LJs being in date.
As it happens, most of the ones I've thrown away have been between 7 and 10 years old and have inflated. Why re-arm an 8 year old jacket?

To be fair I do probably get out on the water more than many people, so I get a reasonable number of hours' wear in 10 years, despite not being the first to put one on in benign conditions.
 
The weighing doesn't have to be super accurate. The gas is either going to be there or not. Even +/- 4 or 5g will be near enough to know if you're missing 38g of CO2.

I'd double check the mystery cylinders for the stamped and measured weight, and also that they are not 60g type (OK if LJ is 275N of course).
 
lw395 said:
A new LJ costs about £50. So that's £5 a year.
The boat set of LJs is four, so £20 a year to have them within the recommended date, vs say a tenner a year if we dragged them out to 20 years.
So we could save maybe a tenner a year split between two co-owners.
In terms of the overall boat budgets, it's cheap.

I've seen enough 15 year old so-called waterproof stuff leak. Enough dodgy zips, broken plastic clips.

I think guests on the boat have a reasonable expectation of the LJs being in date.
As it happens, most of the ones I've thrown away have been between 7 and 10 years old and have inflated. Why re-arm an 8 year old jacket?

To be fair I do probably get out on the water more than many people, so I get a reasonable number of hours' wear in 10 years, despite not being the first to put one on in benign conditions.
Click to expand...

If automatic you can add another £13ish and £20+ for a light every 3 years.
 
I tend to agree with MikeCC. I use kitchen digital scales and confess that often I get strange weight results. IMHO opinion, the condition of the cylinder both for corrosion on the outside and condition of the seal is what matters. I can get a new cylinder for 9 squid. I ( do 15 for the club each year and 4 of my own). Occasional leaky LJ means throw it away. (leaks at seams). I use the old cylinders when too corroded for demo inflation. People should be aware of what an inflating LJ is like. (alarming to say the least)
ol'will
 
I look after the gig club jackets (about 20 of them) and our own (another 6). The regime is identical for all: visual inspection of webbing, casing and bladder. If OK, then a 24 inflation test. At the same time, check weigh the cartridge and expiry date of the capsule. Cartridge replaced if evidence of significant corrosion or weight variation (more than a gram or two lighter or heavier than stamped weight). Capsule replaced if expired or fired.

If the bladder is still inflated at the 24 hour point, then everything is repacked and jacket goes back into service.

I don’t bother trying to find out where bladders are leaking from: if they’ve deflated to any degree, I cut the bladder with a knife and consign it to the recycling bin. However, I’ll repair worn or broken webbing and patch worn casings if needed. Also make a batch of crotch straps every year as people seem to delight in ditching the things.... I now sew the straps in place on the jacket webbing so they can’t be dumped by users who don’t like them.
 
Thought I'd just check before 'knifing' the jacket as to why it was a slow let down .... (in all honesty - its so slow that given Baltic sailing - it would be adequate ... but safety is safety ... so its not for serious use. Maybe on the river where there's always another boat nearby ... )

Mix up some soapy water ..... soft paint brush ... could not find one pinhole or leaking seam at all .... nothing round CO2 bottle ... nothing ... jacket itself is perfect.

Stuck a blob of soapy water in the manual tube and it started to grow bubbles .... so its a tiny leak on the manual sprung valve ......

Before anyone starts crying - Safety Safety ... BIN IT and all that ... just out of interest - I am going to see if there's any way to clean it ... it has me intrigued ...
 
Hours later and it hasn't gone down at all ....... seems the valve has sorted itself ... that soapy water - then pressing the valve a few times to clean and then a long venting to clear it out of tube ...

I'll leave it till tomorrow just to be sure ...........

Normally I only sail two-up - so the other two are enough for usual ... if this 3rd one does stay good .. it will be placed as back-up along with the bouyancy vests I carry as well.

My boat has capability of 5 berths - so I have to have bouyancy items for 5 people according to the register here.
 
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