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View Full Version : DiveCAN JJ, where to connect BOV or necklace reg



Baron015
13-02-2015, 12:51 PM
My old analogue JJ has a beautiful 3-way gas block on the diluent side feeding wing inflate and ADV, with one port spare. That spare port could be used for BOV or necklace reg.

However my new DiveCAN JJ also has a MAV on the diluent side, which means all 3 ports on the gas block are already in use. So out-of-the-box there is nowhere convenient to attach my BOV.

1. I could replace with a 4-port gas block, but the JJ 3-port block is so nicely made, it seems a shame to chuck it.

2. I could use a short hose to plumb in a second gas block to the first one, but then the hose lengths going to wing inflate and/or ADV will be wrong. Plus there will be a lot of hose and blocks going on behind the backplate. Will it all fit ?

3. I could connect another hose to the diluent regulator but its nice to only have one hose on the reg, more flexible when fitting the diluent cylinder.

4. I like the idea to feed the BOV from off-board, but that means going out to buy a whole other set of connectors suitable for disconnect/reconnect underwater, I think ?

What are other people doing ?

First world problems, nice problems to have, etc..

(ps the original version had another constraint, I need to be able to fix it using parts and hose lengths available either in my house or in stock at Amphibian. James is making me a short hose for option 2. However, since tomorrows diving has just been cancelled, I can rethink which is best....)

nickb
13-02-2015, 12:57 PM
I haven't seen the gas routing on the new JJ but from what you imply, the MAV now has its own supply, rather than being plumbed in series after the ADV, is that right? Is the MAV now integral to the unit or can it be removed? I had one for about a week, then removed it.

Baron015
13-02-2015, 01:01 PM
I haven't seen the gas routing on the new JJ but from what you imply, the MAV now has its own supply, rather than being plumbed in series after the ADV, is that right? Is the MAV now integral to the unit or can it be removed? I had one for about a week, then removed it.

Yes the MAV is fed by a new hose going to the original 3-port gas block. Would be pretty easy just to take the MAV off and use that port for the BOV. The attachment to the inject point is just a normal screw-in 2nd stage connection (same as on the O2 side). What do I need to block this off in a watertight way ?

nickb
13-02-2015, 01:08 PM
...but I need a proper watertight plug of some kind for where hose fits or change the knobby bit to the one without the hole.Not quite sure what you mean here mate. On the old system the hole in the t-piece where the, then, optional MAV entered was blanked by a regular 3/8" LP port plug.


I will investigate just taking off the diluent MAV as a short term, maybe long term, fix.An alternative, would be to fit the MAV in the original way. The banjo attached to the ADV barrel was replaced with one that had a passthrough. The original then went into the hole that was blanked off. You'd need the two-way banjo and a new hose. Or you could take my MAV off my hands ;)

Baron015
13-02-2015, 04:37 PM
Not quite sure what you mean here mate. On the old system the hole in the t-piece where the, then, optional MAV entered was blanked by a regular 3/8" LP port plug.


This was the knobby bit. As you rightly point out, once I unscrew it from the T-piece, the hole can be filled with a regular 3/8 LP port plug. Which it now is. Looks like I am all set for tomorrow's dive on the Huntsmoor ..... ah its cancelled due to weather.

http://tapatalk.imageshack.com/v2/15/02/13/3ab30417e4c6b61656ef1e49f90aa93f.jpg

So short term solution is to remove diluent MAV. Longer term I might add it back.

nickb
13-02-2015, 05:53 PM
This was the knobby bitThat is the banjo


So short term solution is to remove diluent MAV. Longer term I might add it back.I like that guy's solution on the JJ Facebook page where he's swapped this bit feeding the ADV with the passthrough one to carry on and beed the BOV.

Can't think why that never occurred to me before as I have the part (from my dil MAV kit) and it would tidy-up the BOV routing. Only downside is that shutting-down the ADV feed (assuming one has an in-line shut-off and I don't) would also shut off the BOV which is bad for two reasons:

a) the BOV should always be pressurised to avoid collapsing the diaphragm and, more importantly
b) no BOV if the shit hits the fan

Baron015
13-02-2015, 08:39 PM
That is the banjo

I like that guy's solution on the JJ Facebook page where he's swapped this bit feeding the ADV with the passthrough one to carry on and beed the BOV.

Can't think why that never occurred to me before as I have the part (from my dil MAV kit) and it would tidy-up the BOV routing. Only downside is that shutting-down the ADV feed (assuming one has an in-line shut-off and I don't) would also shut off the BOV which is bad for two reasons:

a) the BOV should always be pressurised to avoid collapsing the diaphragm and, more importantly
b) no BOV if the shit hits the fan

Maybe it's time to rig BOV to connect to offboard.