DIN Thermo Valve leaking

[Topbodz]

There is a small hole on the side of my thermo DIN valve (same side as the handle) that goes through to the valve chamber where the reg screws into...

I have a scubapro MK25 DIN first stage... I noticed that when the reg is screwed in and valve turned on, it leaks. Slowly but consistantly. I can whatch the pressure drop on my computer...

Is it a problem with the reg connector, or the Oring (I just had the reg serviced) or is there another problem with the valve...

thanks

 

[Rainer]

Try replacing the DIN o-ring.

 

[Bubbletrubble]

The 3 things it could be are: (1) mating surface on your reg, (2) DIN o-ring, or (3) mating surface on the tank valve.
Assuming that everything was working fine before the reg was serviced, I'd be willing to bet that the incorrect size o-ring was installed for the exterior DIN o-ring. This should be super-easy to fix.

First stage reg overhaul kits come with several different sized o-rings. I could see how a reg tech might mistakenly install the wrong one. However, this should have been caught during a routine leak check following reassembly.

I'm not a Scubapro reg guy, so I'm not sure what size DIN o-ring your reg takes. Some regs (like my Apeks) take a -111 DIN o-ring. Most regs take a -112 DIN o-ring.

Probably easiest to just take the reg back to the shop where the reg was overhauled. Explain the situation. They should be able to fix it in a couple of minutes.

FYI, it makes sense to keep -111 and -112 o-rings in your save-a-dive kit...in addition to a lot of other things.

 

[Topbodz]

is there a tool to clean the mating surface on the valve?

 

[Rainer]

Yes, a cloth.

 

[Bubbletrubble]

You could also try connecting your reg to another DIN tank. If there's no leak with the new tank upon pressurization, then the problem lies with the valve on your original tank.

In my limited experience, I've never seen damage to the mating surface of the DIN tank valve (although it's certainly possible). It's much, much easier to install the wrong size DIN o-ring on the reg or damage the mating surface on the reg's DIN connector (part that interfaces with the tank valve) during the cleaning/overhaul process.

 

[Topbodz]

Yes, a cloth.

Well I thought there might be a wire brush of some kind (like the old battery terminal cleaners) made specifically to clean the crud that migh build up on the mating surfaces of the DIN valve..... just saying...

 

[Rainer]

The threads are brass. You don't want a wire brush. You want a cloth. In any case, I've never seen one with enough "crud" to cause issues. Really, you probably just need to replace the DIN o-ring. Just saying...

 

[Topbodz]

OK, I'll try anything once...lol A cloth with??? Soap (like dish liquid) or mineral spirit.... or ??? what would work best?
I'm totally new to DIN equipment....

 

[Rainer]

To start? Just a dry cloth. After that, wet it with water. If it's really bad, try a water-vinegar mixture.

But first try a new DIN o-ring.