Tue Mar 03, 2015 11:18 am
Hey,
Firstly, what was the pressure that you had in the tank when you did your IP check?
If it was at approx. 3000psi your IP gage should be reading about 110-115. If the tank was at 300-500 it should have read around 130-140psi.
To answer your question YES that does sound right if you are leaving the flow open from the lever for more that a second. On some IP gages you will see a pressure spike due to reverse shock wave in the line as pressure is suddenly released, then you will see a uniform fall of pressure from outflow of gas. Of course when you activate the horseshoe lever when pressurized with an IP gage attached and let it free flow for about a second or two you should see a drop of about 30-50 psi., with an fairly immediate return to the original starting IP setting. If this isn't happening follow the guidelines below. I hope the following helps.
Here is the rule for IP set on unbalanced 2 stage regs straight from Bryan's VDH archive:
"Setting the IP on an unbalanced 1st stage can be accomplished in two ways. You can follow the factory recommended procedures outlined in the service manual or use the method below which has been used for many years. Both will give good results with a slight edge in performance going to the method described below.
First you will need a cylinder with 300 psi of air in it. Why so low you might ask? On an unbalanced regulator the intermediate pressure is at its HIGHEST when the cylinder pressure is LOWEST.
There are several posts in the technical section on the mechanics of this and can be found using the search function of the forum. Another great source for all things regulator related is the book Regulator Savvy available at Scuba Tools.com
Secure the cylinder in a horizontal position on your workbench or table. Be sure to have it supported on both sides so it cannot roll off. Insure that the cylinder you are working with has at least 300psi of air and no more than 500 psi. Next attach your assembled regulator to the cylinder and slowly open the valve.
Using a 3/8” hex head wrench, slowly turn the adjustment nut clockwise until you hear a slight hiss of air passing through the 2nd stage. When you hear it stop turning the nut and slowly turn it counter clockwise 1/8th of a turn.
Stop for a moment and cycle air through the 2nd stage a few times by lifting and releasing the 2nd stage nut . Then put the hex wrench back in the nut and slowly turn it clockwise again till a hiss is heard and once again reverse directions by 1/8th of a turn.
Finally turn the air off and lift the 2nd stage nut a few times to bleed off all the air in the regulator. Then turn the air back on and check adjust the IP using the procedure above one final time. When you are sure you have the adjustments correct allow the regulator to set under pressure for 5-10 minutes. If there is no leak during this time your regulator IP is set and you are ready for final assembly. If you are hearing a leak during this time this indicates that your high pressure seat is not seated correctly and needs further attention.
Lastly check the IP with a gauge making sure it is stable and in a range of 130 to 145 psi"
Is the above procedure the one you followed for the 2nd stage?
AS far as IP from the 1st Stage is concerned
If you used just a 3000 psi tank and did your IP set, you might be over pressurizing the reg. At a low pressure (300psi) the IP should be running at approx., 135 psi +/- 5. I use the two tank method, one tank at 3000psi and the other at 300-500psi. I use that Hookah port with an adapter and run my IP gage off that. I check the reg on the 3000psi tank and adjust it for 110psi then I place the reg on the 300 psi tank and check it there. It should read on or about 135. I do this three to four times tweaking a little each time. I then let it sit for a day or two under pressure for set and then re-check IP and adjust as needed.
Trouble shooting: You might either have overpressure situation at low "Tank" pressure (300-500psi), meaning that you need to adjust the adjustment nut and get your IP gage up to 130-140psi IF THE TANK IS AT 300-500psi.!!! OR you might have an UNDERPRESURE situation at high "Tank" pressure (2800-3000psi), meaning you need to adjust your IP at that pressure to 110-115 psi.
"Where'd ya get that ol' thang, don't cha' know them thare things ill kill ya!"
Live From the Red Sea,
Russ