ATM 500

[snark3]

Hey guys. I'm working on a Sportsways ATM 500. The first stage locks up perfectly but only has an IP of 80 psi. I know I need to add washers to increase the IP. Does anybody have a guess how many I should start with? I want the IP in the 125-130 range.

[nikeajax]

Hi Skip, are you using washers, or shims? If you have real shims, they equal five-psi increments. 80-psi seems terribly low: have you looked at your seat?

JB

EDIT: Also, please make sure your bonnet is sufficiently tight

[nikeajax]

Skip, is it the same as the Orca?





I know the vents are different, but...

JB

[snark3]

JB that's the first stage. I did misspeak JB I was talking about the shims.

[nikeajax]

Skip, I was just making sure: if you get too far up a tree, I can help you by tearing into mine, that's all

JB

[nikeajax]

I have actually used washers!!!!!!!!

JB

[snark3]

Thanks JB. I'll see if I can find some locally before I hit you up for some.

[vance]

I always use an IP gauge that has an overpressure valve and a bleed function. I start with the bleed valve open, jic! When you close the bleed valve and pressure is too high, the oprv can kick in.

ALWAYS double check that you have threaded your IP pressure gauge into the LP port! Nasty surprise when you've screwed into HP....!!

[snark3]

Dec 4, 2023 19:52:19 GMT -8 vance said:

I always use an IP gauge that has an overpressure valve and a bleed function. I start with the bleed valve open, jic! When you close the bleed valve and pressure is too high, the oprv can kick in.

ALWAYS double check that you have threaded your IP pressure gauge into the LP port! Nasty surprise when you've screwed into HP....!!

I made a gauge for setup checking IP. It does have a over pressure valve on it. The bleed valve is just a thread in tire valve. It was easy to make and its simple but it works

[cg43]

Hello snark3

Is it right that the ATM 500 second stage has an upstream valve ?
And second question : 80 PSI IP on what tank pressure if the 1. stage is not compensated ? 

If it's upstream and 80 PSI during 3000 PSI tank pressure why will you raise up the IP ?
The reg. will give you more air but breath harder .
If you don't dive this reg. under 100 feet will you ever need the auxilary air volume ?
The advantage of easier breath  you have most the time .

Greetings   Rainer

[nikeajax]

Rainer, to be clear, these are downstream valves. If I remember, OEM setting is 130-psi, which is why I thought it was very odd to have reading of 80-psi, and why I suggested he make sure the bonnet was screwed own tight, make sure the threads are clean/clear too.

Skip, you may want to see if Bill has any shims.

JB

[snark3]

I tested this on a tank with 850 +/- psi. The Sportsways manual says IP should be 110-120 @ 2250. Before I go crazy I think I'll try a tank with more pressure.

Rainer- this is a piston first with a downstream second. I believe it's a flow through piston.

[nikeajax]

Skip, it's a "flow-by" piston, same as most of the Healthways regs: I'm pretty sure the seat is crimped onto the piston-stem too--GRRRRRR!

JB

[snark3]

JB- I'm going to respectfully disagree on the seat being crimped into the piston as the Sportsways manual states "A reversible and replaceable teflon high pressure seat" although I could still be wrong. I thought it was a "flow through" because of the holes in the piston which allow pressurized air to reach the bottom of the piston.

[SeaRat]

Take a look here:

vintagescuba.proboards.com/thread/4947/mystery-port-solved-finally?page=2

The Sportsways ATM 300 is a piston first stage with a pre-set IP, meaning that it isn’t adjustable. But 80 psi is really low. The second stage is downstream, and a very good second stage. Be sure that anything you put into the regulator as a shim or washer is stainless steel.

John