ScubaPro Air flow adjustment key

[baken]

Hello Friends,

I just purchased a ScubaPro MK11/R395 regulator and already inadvertently tossed-out the air-flow resistance key!

Ok, I can take a dulled-tip pair of scissors with me and make a couple adjustments while in the water....but, ...can anyone tell me where these keys are a "dime a dozen"...website, etc.?

Bruce

 

[DA Aquamaster]

What airflow resistance key?

 

[baken]

ScubaPro calls it the "Inhalation Resistance Control", and there are two holes spaced about 3/4" apart, which utilizes a "key" to allow easy rotation - counterclockwise decreases the "inhalation resistance" according to the manual

 

[DA Aquamaster]

The R395 does have an adjustable flow vane - that is the knob located in front of the mouthpiece.

The balanced adjustable regs like the G250V and S600 have knobs to adjust the inhalation effort and the balanced S555 has an inhalation adjustment, but not a knob to allow adjustment in the water.

The important thing here is to realize that the R395 (as well as the R190, R290, R295, R380 and R390) has no mechanism to adjust the inhalation effort other than the internal lever and orifice adjustments. There are two holes for a pin spanner in the plug in the left hand side of the case, but that is to allow a technician to turn the plug 45 degrees to allign the plug in the hole so it can be removed. The end of that plug is square shaped and it rotates out of alignment with the square hole in the case to lock the plug in place. It is also o-ring sealed, but if you turn that plug underwater, you run the risk of losing the plug and you will then flood the second stage.

If that happens you could seal the hole with the palm of your hand and clear the reg, but odds are good you will be switching to your octo in short order.

In short, it is not what you think it is. The hole in the left side of the case is intended to allow the inlet fitting to be switched to the other side of the reg, it has nothing to do with inhalation adjustment.

 

[baken]

Thank you very much for explaining all this - it's clear now.

One question if you don't mind: I've rotated this thing (out-of-the-water...haven't dived yet with it) a few times, just to test the make-shift "key" I was planning to use (clearly, now a moot point), and probably turned it a couple times completely ...say, 720 degrees...have i run the risk of messing this thing up, making the plug "predisposed" to coming out in the water and flooding the 2nd stage???

...from your explanation, it seems I should be ok (just as long as I don't rotate underwater) with what I've done (ie. a couple complete turns already)...now, clearly no need to turn it as it won't make a difference, as you've explained...

Bruce

 

[DA Aquamaster]

The risk here is that the plug has been turned slightly and is no longer locked in place. Normally you would visually inspect it to be sure it is properly located, and you should be able to feel when the plug is engaged. But, short of removing the purge cover and diaphragm, you can probably verify it is secure by sealing the exahust T tightly with your palms and blowing into the reg as hard as you can. If the plug is secure it won't come out.

Not a 100% guarentee, but it is something. If you are close to a shop, have a reg tech check it for you.

 

[baken]

Thanks for the advice and quick response...!

 

[Fishpie]

Baken....nice try, just not this 2nd stage.

The idea would have worked with a G200b, any Apeks or Zeagle.

 

[NC Wreck Diver]

Take your reg to the LDS that you purchased it at and have them adjust the cracking pressure to fit your likes. This will be then set, by the Authorized ScubaPro Dealer/repair facility. As mentioned above, the G-250, S-600, S-700 is adjustable by the diver (VIVA), but regs like you bought are set, then non-adjustable by the diver.

I dive with all Scubapro Regulators and really like them. Keep them washed after diving and get the yearly service done by the Authorized ScubaPro Center. They will give you years of great service. My MK10/G250 is 20 years old, and works like the day I got it. I have moved it as my secondary reg, and dive with a MK25/S700 as my primary. I also use an MK2Plus/R295 Plus for my slung 30. AIR2's on both of my ScubaPro BC's. It has all been flawless.

Good luck and safe diving to you.

 

[baken]

Thanks again!!