VDH DSV Leak by

[EberWolf]

I can't post this on the VDH site right now. My work network doesn't like their site.

I received my Kraken DHR in December last year. I've been able to get 6 dives on it so far, all within the last month and a half. I noticed at the end of my 6th dive when I closed the mouthpiece on the surface air was still bubbling out slightly while I was on my back. I'm 6 dives new to the DHR, never having had one in the past. What should I be looking for as a possible cause?

 

[lexvil]

I can't post this on the VDH site right now. My work network doesn't like their site.

I received my Kraken DHR in December last year. I've been able to get 6 dives on it so far, all within the last month and a half. I noticed at the end of my 6th dive when I closed the mouthpiece on the surface air was still bubbling out slightly while I was on my back. I'm 6 dives new to the DHR, never having had one in the past. What should I be looking for as a possible cause?

You probably need to take it apart and look at the o-rings, try lubing everything if it looks good or order a service kit, you should have received one with the Kraken but if not you should keep one on hand.

 

[Fibonacci]

First step is to plug in an IP gauge and check the IP is steady at ~135psi not climbing at rest (indicating a leaking HP seat), which will eventually over-pressurise and vent via your octo and try to get past the DSV if it is in the shut position.
If IP is OK then as @lexvil says try re-lubing the existing o-rings.
If it still leaks try softer 50 Duro o-rings which will conform a bit better, -028 for the inner barrel and mouthpiece port, -027 for the wagon wheels.

 

[Fibonacci]

Here's an exploded view I prepared earlier... idle hands being the Devil's Workshop

Updated to include mouthpiece o-ring...

 

[EberWolf]

Thanks for the Pic. If you ever watched Futurama you'd know The Devils Hands are Idle Playthings.

How easy is it to take apart and reassemble?

 

[Fibonacci]

Dead simple to disassemble, just remove the large black nylon screw and the inner barrel assembly will slide out from the RHS.
The wagon wheels can usually be popped out by carefully poking a soft wooden chopstick down the mouthpiece aperture and pushing on the edges of the wheel till you can grasp it with your fingers. The o-rings can then be changed.
Make sure the wagon wheels and inlet/exhaust valves are oriented as in the diagram.

The trickiest part on reassembly is to ensure the o-ring around the mouthpiece aperture doesn't get cut or dislodged when you replace the barrel assembly. Use a slight twisting motion as you press it in and it should pop straight in.

 

[EberWolf]

I ordered a DSV repair kit but it might take a few weeks to months to get here. Can I use off the shelf gaskets? Size?

 

[Couv]

What should I be looking for as a possible cause?

Here's an exploded view I prepared earlier... idle hands being the Devil's Workshop

Nice diagram, but un-idle your hands and add the o-ring that goes around the square part of the mouthpiece opening.

@EberWolf here is a vid you may find helpful:

 

[herman]

Before going too far, can you better define "when I closed the mouthpiece on the surface air was still bubbling out slightly while I was on my back." Was air coming out the DSV or was air coming out the exhaust on the cans? If air was coming from the DSV, then service of it might be in order. If there was air leaking from the second stage and coming out the exhaust in the cans. that is a completely different matter and not related to the DSV.

 

[EberWolf]

Air was bubbling from the mouthpiece.