Mares Axis 2nd Repair Questions

[Former FLL Now MSP Diver]

My Axis octo free flows with varying degrees of severity fairly often, and a quick run into the shop gets it fixed in a minute or two.

I've watched and they only adjust the small hex nut that moves the lever that rests against the diaphram.

My octo free flowed over the weekend (badly enough causing me to thumb the dive), and the other night I thought I'd try fixing it myself. I backed the hex nut off 1/6 of a turn (one side of the hex nut) and it stopped leaking air. Twenty minutes at the bottom of the pool showed no problems with leaking or breathing through the reg.

I used a small pair of needle nosed pliers to turn the nut from the front of the reg after unscrewing the faceplate. This isn't the best way to do it as a little slip you could potentially bend the lever that rests against the diaphram.

There's a plastic plug that can be removed with an allen key on the opposite side of the valve. Unfortunately it's a size that I don't have. Also to get to the hex nut I'll need a long handled nut driver.

Can someone tell me if the hardware is metric or imperial, and specifically what size allen key and hex nut driver are used on the reg?

Marc

 

[chrispete]

The "plastic plug" that you are talking about is the teflon crown orifice that rests against the LP seat. This is where you _should_ do the adjustment for the reg. If you are having constant problems with this reg, it may be that the seat is damaged or there is a nick in the crown. I would have the LDS replace the seat and check the crown for damage.

A small word of warning from personal experience: If the nut used for lever height adjustment on a classic downstream reg is backed too far off it can actually work itself loose (the only failure where a reg will fail completely and not freeflow or give any air for that matter.) I have had one of my octos do exactly that and it wasn't found out until the octo was needed, thankfully in a controlled situation with a very experienced buddy so we were able to buddy breathe through the exercise. Try if possible to make most of the adjustments from the crown side of the reg.

 

[Former FLL Now MSP Diver]

I think we're talking about 2 different plastic plugs.

The plug I'm referring to is on the opposite side of the LP house inlet on the outside of the regulator casing. It appears that it's there to allow access for a long handled nut driver to adjust the hex hut on the lever that rests against the diaphram.

The reg itself had it's yearly service back in May, so the seat is new. This is the first time it's leaked since the service, but past experience is that it will continue to do this every few dives.

I did have another LDS (a non-Mares shop) tell me once that these Mares are known for their soft valve seats since they changed them to the new plastic material, and they do need constant adjusting as they wear. I'd like to be able to do it myself properly so that I don't have to run to the shop every few weeks. Watching what they do has lead me to think it's not that hard.

Marc

 

[DeepScuba]

FLLDiver:

Allow me to wade in.

The plastic plug YOU are referring to is not the one chrispete is referring to.

As you suspected.....

The nylon lock nut, that you get to via removing the plastic plug IS NOT the adjusting point.

YES you can adjust that to obtain a possible "working" reg situation, but the resultant setting, depending on the adjustment at the other end (Hose end) would probably result in a VERY HIGH inhalation effort to obtain ANY air at depth.

The lock-nut setting, if you can call it that, is, I THINK, about "3 threads" showing out the end of the nut.

That's a bogues setting from Mares, but that's all I could ever get.

The REAL setting is done via the "hose" (removed), end with an "allen key"??

You should only turn the allen key when the purge button is depressed, so you don't "chew" the rubber seat with the adjustable poppet seat/orifice (Metal)

That being said, I am NOT a Reg Tech, so take what I write with the appropriate skepticism!

BUT......been there, done that, is how I know

I don't own an Axis, but I've seen many many free-flows on them. The soft valve seat are the culprit..........Mares says they aren't a problem.but of course only on "New" soft design has this been a problem.

Mares...wake up.

 

[neil]

Before you do anything, you need to determine WHY the reg is freeflowing.

-turn the air on- if after a few seconds the reg starts to freeflow, check the intermediate pressure, that's a first stage leak, MAYBE.

-with the air on and the reg freeflowing, take the top and diaprhragm off. If the reg still flows, the orifice needs adjusting.
If the flow stops with the diaprhagm off, that's usually a sure sign that the lever is too high and needs lowering as you've already done.

You really should adjust both variables each time you adjust the reg. As the seat wears, the lever will ride a little higher causing the freeflow. An inline tool will make this adjustment much faster, and they're not that expensive. Get an IP gauge while you're at it. Try www.scubatools.com.
The plug uses a metric allen, don't know what size. The locknut is 5.5 mm which I think works out to 7/32". You do the math!

Neil

Disclaimer: Mess with your own reg at your own risk.

 

[Former FLL Now MSP Diver]

neil once bubbled...
Before you do anything, you need to determine WHY the reg is freeflowing.

-with the air on and the reg freeflowing, take the top and diaprhragm off. If the flow stops with the diaprhagm off, that's usually a sure sign that the lever is too high and needs lowering as you've already done.

This is the problem. It always stops when the faceplate is lossened and removed. And I've watched them at the dive shop only make this small adjustment to stop the leaks.

You really should adjust both variables each time you adjust the reg. As the seat wears, the lever will ride a little higher causing the freeflow. An inline tool will make this adjustment much faster, and they're not that expensive. Get an IP gauge while you're at it. Try www.scubatools.com.
The plug uses a metric allen, don't know what size. The locknut is 5.5 mm which I think works out to 7/32". You do the math!

Exactly the info I needed. I'll also look for the tools there. Thanks

Disclaimer: Mess with your own reg at your own risk.

Point taken. Believe me, if I thought for a minute there was really anything wrong with the reg it would be into for a real service. I do not have a death wish.

Marc

 

[DeepScuba]

Two things I should mention.........

I still haven't read where you said that when the frt cover is tunscrewed it stops leaking!!!

It should have been obvious that the lever height was too high........you should have a slight lever clearance when the cover is tight.

Secondly, I didn't mean to imply the "nut" adjustment was irrelevant, but had to be set "ballpark" for lever height etc, but this shouldn't have changed anyways from pre free-flow to post free-flow, meaning the adjustment is required at the "hose" end.

Again, the IP check is basic as well, but there again, it's almost 100% that that isn't the problem given your description of the problem. But hey, I regularly check mine since it's a 2 second job, just for fun.

Back the lever down a smidge, and dive it for a bit, until it flows....or not. Then go for the "hose" end adjustment, as this is where it's done.

Oh yeah........DON'T tighten the plastic access plug too tight!!!!!!!! A common error causing much grief.

AT your own risk, of course.

I know nothing, and am not a professional anything