Minor octo freeflow = minor adjustment?

[amajamar]

I have a Oceanic FDX-10/Delta 4 primary regulator with a Dive Rite octo. On the past few dives I've noticed that the octo gives a very brief freeflow just as I submerge and if I wave it around while submerged, it will freeflow until I stop. I'd like to make whatever adjustment required, but I don't want to make an error. My conclusion is that the adjustment is on the little nut on the inlet valve behind the cover plate and diaphragm, but if someone can confirm that would be great. Also, would the adjustment be clock or counter-clockwise?

Thanks in advance!

 

[halocline]

It's normal for a well adjusted 2nd stage to freeflow in the type of situation you're describing. Once you get in the water, try to keep the mouthpiece pointing down and/or covered. When the stage gets flooded with water it shouldn't freeflow. It probably does not need any adjustment. If there's a venturi assist knob you can turn that to minimum, but I would not adjust the cracking pressure unless the freeflow is not controllable by positioning and flooding the reg.

How you adjust the cracking pressure depends on what type of design it is. It's often done by adjusting the orifice, found by removing the hose. Then on some there's a second adjustment (on some, this is the only adjustment) via the little nylock nut that positions the lever. Others have a barrel that runs across the reg for the air to flow through, those are almost always adjusted by moving the orifice.

 

[Zung]

The service manual of the Delta 4 is here.
For a quick & dirty fix, remove the hose, hold down the purge and turn the orifice (item #11) 1 hour (30°) clockwise. If you want to be thorough, remove the cover, check the lever for slack, and tighten the nut (#20) if required.
I like my octo a bit hard so it doesn't bother me with freeflows.

 

[amajamar]

Thanks Zung,

What about a Dive Right octo? Cause that's what it is. Do you think it's relatively the same?

 

[Zung]

The manual is here, page 95, same procedure, the orifice is item #14X, and the nut is #18.

 

[amajamar]

The manual is here, page 95, same procedure, the orifice is item #14X, and the nut is #18.

Totally Awesome, thanks so much!