Servicing your own regulators

[flymolo]

I watched a couple you tube videos. Assuming they did it right the hardest part seems to be making sure you install the right oring into the right spot.

How much are apeks and aqualung service kits?

You should have someone walk you through it the first time. But after that, just following the service manual will get you most of the way there. Troubleshooting problems is a different story though.

 

[rsingler]

You should have someone walk you through it the first time. But after that, just following the service manual will get you most of the way there. Troubleshooting problems is a different story though.

Service Manuals don't tell you to not use a steel pick to remove an oring.

Manuals don't often tell you to not use a screwdriver to pry out an old dry diaphragm.

Manuals don't tell you to use a wooden dowel or plastic crochet hook to pluck out the high pressure oring buried deep in the balance chamber.

Each of those examples was from a regulator that had been serviced, had leaks due to damage and was now a brass doorstop.
It ain't rocket science, but it is precise. It's taken me years to become truly proficient. I'm afraid you need more than the manual. My 2 cents.

 

[lowwall]

Angelo, I'm not sure you are fully understanding the difference in seating forces between balanced and unbalanced 2nd stages, or at least you are not articulating it well. Yes, an unbalanced reg has more force against the seat when not pressurized than a balanced reg. But there is no difference when they are pressurized; they both have exactly the force needed to seal the seat at a given cracking pressure. When the reg is adjusted to the point of barely freeflowing, that means that the seat is not pressing against the orifice with sufficient force to close the valve. It doesn't matter whether it is just a large spring (unbalanced) or a small spring and a portion of IP (balanced) providing that force against the downstream force of the air coming from the 1st stage.

It makes no sense to use an inline tool with the purge pressed, because the whole point of the inline tool is to be able to adjust the 2nd stage while pressurized. Once you press the purge, it no longer functions in that way. You could, I guess, attach everything, then turn off the tank, purge to empty the pressure out of the regulator, press the purge, then turn the orifice with the inline tool, then turn the tank back on, check for freeflows, and repeat this process over and over until you have it set where you want it. But that's not really different than simply removing the hose and adjusting the orifice with a screwdriver.

Halocline,
I've read over several of the servicing threads, current and historical, and you consistently provide the clearest explanations on them. This kind of technical writing is a real skill and I thank you for sharing it with us.

 

[Open Ocean Diver]

Angelo, I'm not sure you are fully understanding the difference in seating forces between balanced and unbalanced 2nd stages, or at least you are not articulating it well. Yes, an unbalanced reg has more force against the seat when not pressurized than a balanced reg. But there is no difference when they are pressurized; they both have exactly the force needed to seal the seat at a given cracking pressure. When the reg is adjusted to the point of barely freeflowing, that means that the seat is not pressing against the orifice with sufficient force to close the valve. It doesn't matter whether it is just a large spring (unbalanced) or a small spring and a portion of IP (balanced) providing that force against the downstream force of the air coming from the 1st stage.

It makes no sense to use an inline tool with the purge pressed, because the whole point of the inline tool is to be able to adjust the 2nd stage while pressurized. Once you press the purge, it no longer functions in that way. You could, I guess, attach everything, then turn off the tank, purge to empty the pressure out of the regulator, press the purge, then turn the orifice with the inline tool, then turn the tank back on, check for freeflows, and repeat this process over and over until you have it set where you want it. But that's not really different than simply removing the hose and adjusting the orifice with a screwdriver.

When does the benefit of the lighter spring come into play?

 

[Angelo Farina]

When does the benefit of the lighter spring come into play then?

The lighter spring means that during storage there is not a strong force acting, so the seat is degrading more slowly.
But the great advantage of a balanced second is that it will work well over a range of IP values...

 

[halocline]

When does the benefit of the lighter spring come into play?

Angelo's explanation in the most recent post is correct. The two main benefits are less pressure on the seat in storage and the ability to work well with fluctuating IP.

There is one other, more subtle benefit. Less effort is needed to keep a balanced 2nd stage valve open once it has cracked and air is flowing. This is because a portion of the closing force (upstream) is provided by air in the chamber at IP. Since IP drops when the valve opens and air is flowing, so does that portion of the opposing force in the balance chamber. This should have an effect on total WOB but it's not that noticeable in use. I have spent a lot of time diving with both balanced and unbalanced 109s, and it's difficult to tell much difference. IME the tune lasts longer on the balanced ones that I own.

 

[Open Ocean Diver]

Angelo's explanation in the most recent post is correct. The two main benefits are less pressure on the seat in storage and the ability to work well with fluctuating IP.

There is one other, more subtle benefit. Less effort is needed to keep a balanced 2nd stage valve open once it has cracked and air is flowing. This is because a portion of the closing force (upstream) is provided by air in the chamber at IP. Since IP drops when the valve opens and air is flowing, so does that portion of the opposing force in the balance chamber. This should have an effect on total WOB but it's not that noticeable in use. I have spent a lot of time diving with both balanced and unbalanced 109s, and it's difficult to tell much difference. IME the tune lasts longer on the balanced ones that I own.

After reading your explanation, Robs, and Angelos then going back and rereading Savvy chapter on balanced downstream valves, click click... I have a greater understanding and appreciation of partial air balancing design... thanks to you three Amigos.

 

[shurite7]

Service Manuals don't tell you to not use a steel pick to remove an oring.
View attachment 646896 View attachment 646893
Manuals don't often tell you to not use a screwdriver to pry out an old dry diaphragm.
View attachment 646897
Manuals don't tell you to use a wooden dowel or plastic crochet hook to pluck out the high pressure oring buried deep in the balance chamber.
View attachment 646894
Each of those examples was from a regulator that had been serviced, had leaks due to damage and was now a brass doorstop.
It ain't rocket science, but it is precise. It's taken me years to become truly proficient. I'm afraid you need more than the manual. My 2 cents.

All of these comments ring so true. I’ve taken troubled regs with me to renewal seminars. In some cases many of the other techs had not seen, let alone dealt, with certain issues. Reg service classes can teach you how to service a reg and give tips to some of the simple common issues, but the courses cannot provide a student with “how to” for all unexpected rare issues that crop up. This is something that I learned while taking an electronics course back when I was in the military; the course was thorough, but could not cover every problem, something I learned out in the fleet.

 

[cburgert]

My short answer would be. I have magic fingers, what ever I touch I break. I'd still take a class though.

 

[Jim Lapenta]

Service Manuals don't tell you to not use a steel pick to remove an oring.
View attachment 646896 View attachment 646893
Manuals don't often tell you to not use a screwdriver to pry out an old dry diaphragm.
View attachment 646897
Manuals don't tell you to use a wooden dowel or plastic crochet hook to pluck out the high pressure oring buried deep in the balance chamber.
View attachment 646894
Each of those examples was from a regulator that had been serviced, had leaks due to damage and was now a brass doorstop.
It ain't rocket science, but it is precise. It's taken me years to become truly proficient. I'm afraid you need more than the manual. My 2 cents.

The manuals I write do all of that. As well as telling the user to treat every reg as if it was going to be used with O2. Just because the cleaning and inspection procedures are good practice.