MK25?

[buddhasummer]

Cool! Thank you!

Most welcome.

 

[Dan]

Make a sandwich. It could take quite some time for the supply pressure to fall far enough to show on the IP gauge. If the leak happens to be in the HP circuit you may never see it on the IP gauge.

Why don't you want to use your SPG?

I do have the SPG hooked on the high pressure side. It will also can be used to test for any leak on the high pressure side of the 1st stage regulator. So, once I check there is no leak on the high-pressure side via the SPG, then I should bleed down the high-pressure side by purging the air out through the 2nd stage until the pressure in the SPG reading about 200 psig or whatever the low pressure side should be at, before checking the leak in the low pressure side?

 

[halocline]

I do have the SPG hooked on the high pressure side. It will also can be used to test for any leak on the high pressure side of the 1st stage regulator. So, once I check there is no leak on the high-pressure side via the SPG, then I should bleed down the high-pressure side by purging the air out through the 2nd stage until the pressure in the SPG reading about 200 psig or whatever the low pressure side should be at, before checking the leak in the low pressure side?

You're thinking about the IP gauge as a leak detector and it's not really for that. What you want to see on the IP gauge is solid IP that does not creep up. You check for leaks in the LP side of the 1st stage by submerging it while pressurized. Even when supply pressure goes below IP and the IP gauge does drop, you haven't isolated the leak; it could be in the HP side.

Here's a quick rundown of how to leak test.

1. Put the reg on a tank, leave the valve closed.
2. Suck on each 2nd stage, hopefully you get no air. This is a vacuum check.
3. Turn on the valve, check IP, tap the purge a few times, make sure IP is stable.
4. Turn the valve off, watch the SPG. If it starts dropping (it can be very slow) usually its a problem with the tank valve o-ring.
5. Turn it back on, take the IP gauge off, submerge the reg and tank, look for any bubbles. If you see a small stream of bubbles from where the reg meets the valve, that's why your SPG was dropping.

You can skip step 4, just make sure you don't forget to remove the IP gauge before dunking your tank in the tub. Guess why I never forget to do that....anymore.

 

[Dan]

You're thinking about the IP gauge as a leak detector and it's not really for that. What you want to see on the IP gauge is solid IP that does not creep up. You check for leaks in the LP side of the 1st stage by submerging it while pressurized. Even when supply pressure goes below IP and the IP gauge does drop, you haven't isolated the leak; it could be in the HP side.

Here's a quick rundown of how to leak test.

1. Put the reg on a tank, leave the valve closed.
2. Suck on each 2nd stage, hopefully you get no air. This is a vacuum check.
3. Turn on the valve, check IP, tap the purge a few times, make sure IP is stable.
4. Turn the valve off, watch the SPG. If it starts dropping (it can be very slow) usually its a problem with the tank valve o-ring.
5. Turn it back on, take the IP gauge off, submerge the reg and tank, look for any bubbles. If you see a small stream of bubbles from where the reg meets the valve, that's why your SPG was dropping.

You can skip step 4, just make sure you don't forget to remove the IP gauge before dunking your tank in the tub. Guess why I never forget to do that....anymore.

Thanks for the tips!

 

[Dan]

I understand better on the use of IP gauge after reading this section of Regulator Inspection and Checklist (Rev-7):

"9. Intermediate pressure check. Get a scuba regulator intermediate pressure gauge:
Tech Diver IP Gauge - Universal Inflator
Intermediate Pressure Gauge Plugs Into The BCD Quick Disconnect Hose
You can also put one together or your LDS may have one for sale.

Find out what the IP range should be for your regulator (most are ~ 135 +/- 10 psi.) Connect your regulator to a tank and open the tank valve. Connect the IP gauge to the LP inflator hose, and lightly press the purge a few times to "cycle" the regulator.

The intermediate pressure should dip whenever the air is flowing, and immediately return to the acceptable range and remain steady. If it tends to climb (creep) that indicates there is a problem with the first stage that must be corrected. It's not a bad idea to leave the regulator pressurized with the IP gauge connected for several minutes to check for slow IP creep.

It should be noted that the IP of balanced and non- balanced first stages react differently to changing tank pressures. Balanced first stages should keep a relatively constant IP over the entire range of tank pressure. Any significant changes in the IP indicate a first stage problem. The IP of non-balanced regs will vary up or down by several PSI as tank pressure varies, the amount and direction of the change varies with regulator design."

It doesn't say to be used for leak check.