valve service kit

[stepfen]

Hello,
I recently bought a second hand steel tank and although it has been recently hydroed the valve apparently hasn't been serviced and as a result the knob is very tight. So I am thinking to service/lubricate the valve myself. I think I'd better overhaul the valve just to be sure.

From searching online I get the impression that there are at least 2 types of valves with corresponding service kits. One that uses a copper ring and one without it. Is it so?

How can I know what service kit I will need? The valve is this one

I live in a small city with very limited supply for diving stuff and shipping things from abroad takes from a week (Europe) up to 2 months (from Asia - freaking customs!) , hence I would prefer to have the service kit in hand before I disassemble the valve.

If it is only about o-rings I can get them locally (if I know their dimensions) and I also have a generic diving o-ring kit (including for example tank o-rings) .

As for the procedure, I've fount in frogkick a maintenance guide for valves from sherwood describing it. Looks not so difficult, especially given that here in Europe we don't use burst disks hence I don't have to tongue it precisely.

Any more related resources would be very welcome.

Another question, I read that steel tanks should not be left open or empty. Of course I don't plan to bring the open tank anywhere near water, but can leaving it exposed (while I clean/service the valve) to the atmospheric air cause any problems?

Thanks in advance.

 

[JackD342]

I have no idea what is inside a Seaway valve, but there are more than just two types of service kits. Be sure you actually KNOW that what you are using is appropriate for this specific valve rather than just guessing/assuming from a choice of generic kits. For instance the valve sold as a Genesis brand in the US is made in Europe, (France I think?) and has very different internals than a Sherwood valve, even though Sherwood owns the Genesis brand. I think the Blue Steel valves sold in the US are also a different style EU import item. Probably another dozen examples out there. Even within the common "generic" kits for the much copied Sherwood style valves, there can be differences in the threads on the seat plug.
CONVERTIBLE 200 BAR YOKE/DIN VALVE - KA-70 | product

 

[guruboy]

Sell it and buy another one that you know about.

 

[happy-diver]

Yeah I just clean and change orings and throw a cloth over the neck

Dudes and dudesses! maxdive2007 on ebay

When I found this place I went to heaven for a little bit
but you have to water your own horse

 

[stepfen]

Few days ago I went forward and disassembled the valve to see first hand.
Pars looked in great shape so I cleaned and lubricated everything and put it back together.
The knob now turns smoothly, there are no leaks (had a dive with it this morning), and lastly now I know what is hidden inside:

Stupid me I forgot to measure the diameter of the seat :S
From the look of it, it looks very similar to the Halcyon assembly (eg here https://www.divesupport.de/Cylinders-Accessories/Valves/Halcyon-Valve-Service-Kit::375.html )
I wish somebody had access to the Halcyon kit to confirm that their dimensions match.
I'll wait a bit for an answer, but given the cost of the kit (~15euros), soon I'll go ahead and order it anyway, hoping for the best.
For now that valve is good to go - it is just that I don't know when it was rebuilt last time. Tank is 10 years old hence maybe the valve is that old too (although barely used).
Thanks a lot for all the input anyway.

 

[rjack321]

Halcyon doesn't make valves, they rebrand other company's valves. You have a standard (at least for USA valves) seat with coarse threads. Also used by Sherwood and thermo. You shouldn't need to replace the seat for many years.

 

[fmerkel]

If it's working well, and not leaking, I wouldn't worry too much about it. Parts look pretty new actually. The wearing parts are the O-ring and teflon washer. The rest generally just need cleaning.
The only seat I've ever replaced were on some OMS tanks years ago that came with crap seats that disintegrated within a year. Replacements are still going.

 

[stepfen]

You have a standard (at least for USA valves) seat with coarse threads. Also used by Sherwood and thermo. You shouldn't need to replace the seat for many years.

If it's working well, and not leaking, I wouldn't worry too much about it. Parts look pretty new actually.

Great info. I was thinking to replace everything based on the 5 years interval manufacturers suggest. Based on your suggestions and since the parts look in very good condition I'll postpone it for now.

The spindle looks a bit different than the most common ones I find on-line. It has this metal flap (I don't know how else to describe it, anyway I mean the thing that is located at 12mm point in the picture above) sandwiching the o-ring and the Teflon ring.

Anyway thanks for the great info.

 

[rjack321]

Great info. I was thinking to replace everything based on the 5 years interval manufacturers suggest. Based on your suggestions and since the parts look in very good condition I'll postpone it for now.

The spindle looks a bit different than the most common ones I find on-line. It has this metal flap (I don't know how else to describe it, anyway I mean the thing that is located at 12mm point in the picture above) sandwiching the o-ring and the Teflon ring.

Anyway thanks for the great info.

If the seat has more than a 1mm indentation in it from the sealing crown or isn't sealing properly then replace it. Otherwise juts wash it in simple green and reuse. They can last for 10yrs, possibly more depending on how often the cylinder gets used.

That valve stem is common on some of the halcyon branded valves which are apparently made by the same people who manufactured your valve. The only real difference is the use of 2 Teflon packing washers with the one up against the oring having a split in it. The stem diameter is otherwise the same and if you can't find an official split Teflon washer you can just cut a round one to slip it in there. Or replace the stem with a standard one and use a single thick Teflon packing washer. Teflon packing washers last about as long as the HP seats though 10+yrs isn't uncommon.

The only parts you will for sure need to replace are the stem oring, the bonnet nut oring, and the valve to cylinder oring. Everything else can be washed and reused if they're in good condition.

 

[Wookie]

I rebuild valves in rental no more than annually, and as required before then. I replace the burst discs at hydro.

My tanks don't get used near as much. I inspect them annually, and rebuild them at hydro.