Cracking pressure

[neil]

drouge,
Take the ATX200 to someone who is qualified to work on it. The reg can, in just a couple of minutes be adjusted better. I like mine adjusted so that with the knob all the way out, the reg just freeflows slightly, even though this is not the "factory correct" setting. Also, did you have the other adjustment on the "+" setting?
Having said all that, you really should try it in the water. Cracking pressure is not an indicator of reg performance, really, unless it's truly excessive.
Neil

 

[tubaloo]

x

 

[Drew Sailbum]

Cracking pressure - the pressure you must apply by inhaling before the valve in the second stage is opened and air is allowed to flow from the tank. This is the amount of pressure to "crack open" the demand valve.

Roughly corrosponds to the work required to breathe. Cracking pressure can be adjusted by a trained technician.

If cracking pressure is too high, breathing is hard work. If cracking pressure is too low, the reg may free flow frequently.

 

[tubaloo]

x

 

[neil]

I think that't only partially correct. Once the valve is open, there are other factors that help keep it open, such as venturi vanes, vortex tubes and the like. That's why I said that cracking pressure is not a major indicator of reg performance. If the valve stays open effortlessly while inhaling, that's a good indicator. Imagine if you had to keep "sucking" on it the whole time you were breathing in.

Here's a simple test for cracking pressure. Take a pressurized 2nd stage and put it in a container of water slowly, mouthpiece up, keeping the reg level. The valve should open when the diaprahgm is about 1.3 to 2 inches under (from the APEX manual. I think 2" is a little high) the water level. Don't let water into the mouthpiece. Do it a couple of times. On your ATX200, the diaphragm is just about where the joint between the case and cover meet. I would do this test with the knob turned in about a half turn. You should be getting a little air flow with the knob all the way out.

In any case, take it to a technician for a little tweak if you are unsure.
Neil

 

[drouge]

Thank you Neil and Drew. And thanks to all for the greetings, I will try to callus up a little. And i will take my brand new ATX200 in for tuning. But when I bought my new motorcycle, it came tuned up. I guess i fell into the marketing hype. My mistake, won't happen again. Thanks again to all.

 

[Uncle Pug]

Originally posted by drouge
But when I bought my new motorcycle, it came tuned up. I guess i fell into the marketing hype. My mistake, won't happen again. Thanks again to all.

Not necesarily Drouge...
I've never heard of that situation before...
I have a bunch of Apeks and all performed flawlessly out of the box...
You just happened to get one that needs a little attention...
I would be very interested to hear what the diagnosis turns out to be....
Please keep us posted.

 

[drouge]

Will do.

 

[Rick Murchison]

If I've read right, you didn't have it hooked up to a tank with the air on when you first tried it - is that right?
Have you had it in the water yet?
I'm a little concerned, and here's why - when a regulator isn't hooked to the tank, with the first stage dust cap in place, you shouldn't be able to draw on it at all. Properly sealed exhaust ports should prevent your being able to draw any air by them, and none should be available from the first stage. My concern is that you may have sucked an exhaust port flapper (seal) into the exhaust port, and when you get in the water you're going to have one hell of a leak into the second stage through it.
If I've read the thread wrong, my apologies. If not, get the exhaust port(s) checked. (don't know how many the Apeks has)
Rick