Regulator checklist and inspection

[Couv]

Could a MOD please make this thread a sticky?

Here is a regulator checklist put together by the Usual Suspects: LuisH, Mattboy, Awap, and Couv and an assortment of others we stole ideas from. We hope this helps.

Regulator checklist and inspection: Here are a few checks that everyone is capable of doing.

1. Inspect for external corrosion or physical damage to any parts including hoses. Pay particular attention to the hose to fitting interface for any signs of damage.

2. Inspect the first stage inlet filter for discoloration, particulate matter or any other signs of water intrusion.

3. Check each hose connection to see that it is at least hand tight. It is an essential check after service or reassembly and a good check to make occasionally after that.

4. Next, watertight checks are also very easy to perform and check the integrity of the second stage housing. Connect the regulator to a tank and without turning on the air (or if you have a good tight dust cap you can use that instead) draw a breath on the second stage and hold it for a few seconds. Do not draw too hard as it will collapse the exhaust valves and cause a leak. Does the regulator hold vacuum? If so, then it is probably watertight.

5. Check for air leaks by putting regulator on a tank and with the pressure on, first listen to any leaks, but the definite answer comes by submerging all parts of the regulator in a water tub or similar container. Check the first stage, the second stages, the pressure gauge, and all the hoses with special attention to all the fittings. Check around any hose connections as well as all around the first stage and out the mouthpiece of all second stages for small bubbles.

6. Intermediate pressure check. Get a scuba regulator intermediate pressure gauge: Intermediate Pressure Gauge Plugs Into The BCD Quick Disconnect Hose from LeisurePro.com

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.

7. Another check is the cracking pressure of each second stage. Partially fill your kitchen sink and immerse the pressurized regulator with the mouthpiece up. Air should begin to flow before the regulator gets more than 1 1/2 inches deep. If the mouthpiece is submerged before the regulator starts to flow, the cracking pressure is probably too high.

8. A tiny bit more advanced, remove second stage diaphragm cover to inspect for any corrosion, damage, sand or any other contaminants. Clean sand and contaminants as necessary. On some regulators it is very easy to open and inspect second stages, but not all. It is a good idea to learn how to open your second stage to clean it. Note: If you do not feel comfortable opening up your second stage, this step can be omitted.

These simple checks can be done by anyone. They should be done prior to any dive trip, not to mention when new out of the box or after shop service.

Check early, check often.

Some very good sources of information:
Vance Harlow's (Oxyhacker on Scuba Board and elsewhere) "SCUBA Regulator Maintenance Repair." SCUBA REGULATOR MAINTENANCE AND REPAIR by Vance Harlow
The Scuba Tools book, "Regulator Savvy" Scuba Tools

 

[soudan]

8. A tiny bit more advanced, remove second stage diaphragm cover to inspect for any corrosion, damage, sand or any other contaminants. Clean sand and contaminants as necessary. On some regulators it is very easy to open and inspect second stages, but not all. It is a good idea to learn how to open your second stage to clean it. Note: If you do not feel comfortable opening up your second stage, this step can be omitted.

Hey,

Thanks for the tips.

I did find a bit of corrosion inside my second stage, and i dont really know how to deal with it, and i dont have any maintenance centers around me where i can take the regulator to! so what would you recommend i do to remove the corrosion?

 

[redacted]

Hey,

Thanks for the tips.

I did find a bit of corrosion inside my second stage, and i dont really know how to deal with it, and i dont have any maintenance centers around me where i can take the regulator to! so what would you recommend i do to remove the corrosion?

A little corrosion in a 2nd stage is an indicator that you need to do more soaking after SW dives but, unless it is causing a problem somehow, I'd leave it until the next service. Just keep an eye on it in the mean time to make sure it does not get worse.

 

[soudan]

Thanks awap.
The Reg. is fine, i just don't like seeing corrosion on my equipment!

I guess i need to do a better job cleaning it after a salt water dive. I'll keep that in mind the next time i dive.

 

[demisvmax]

7. Another check is the cracking pressure of each second stage. Partially fill your kitchen sink and immerse the pressurized regulator with the mouthpiece up. Air should begin to flow before the regulator gets more than 1 1/2 inches deep. If the mouthpiece is submerged before the regulator starts to flow, the cracking pressure is probably too high.


There is something I didn't understand in step seven.
The regulator should have flow before or after the mouthpiece is submerged? Does this has to do anything with free flow? And adjustment of cracking pressure is the work of the repair shop, correct?
Thanks,

 

[Couv]

Hi Demisvmax,

Regulator second stages have a diaphragm inside. During normal use, one side is exposed to water (hydrostatic pressure) and the other side is dry. The diaphragm not only keeps the side you inhale dry, it actually performs the work (through mechanical linkage) of opening the air valve. So the key is how far the diaphragm can submerge (mouthpiece up) before the air valve opens. This is known as the "cracking pressure" and is usually measured in inches of water. Now, it may not be easy to determine exactly when the diaphragm is first exposed to water pressure, so we used the term "regulator". At any rate, when the regulator second stage is submerged, air should begin to flow before the mouthpiece is under water.

The second part of your question: Yes, if the cracking pressure is too high (or too low) it is time for a visit to someone familiar with servicing your regulator.

Edit:

Vance Harlow's (Oxyhacker here on Scuba Board) book Scuba Maintenance and Repair does and outstanding job of explaining the above. Here is a link to an excerpt from the book worth reading.

http://airspeedpress.com/regread.html



couv

 

[Couv]

Here is another checklist from DA Aquamaster; I especially like #4 as we forgot to put it in the original and is very helpful if one does not have an IP gauge.

I agree with Herman that the value of the test lies not in the value but rather in how solid the lock up is and the abscence of any IP creep.

I recommend divers do some basic pre-dive checks.

1. Hook the reg up to the tank. Before you turn on the tank valve, try to inhale from the reg. You should not get any air or hear any leaks. If the reg fails this vaccuum check you probably have a leak in the exhaust valve, the diaphragm or in one of the o-rings sealing the case or through a crackin the case itself.

2. Pressurize the reg. Depress the purge slightly. If you have to depress it more than a very slight amount before airflow starts, the lever may be improperly adjusted, reducing the working range of the valve and the flow rate of the reg.

3. Breath off the reg to ensure it breathe normally and does not freeflow even slightly after the last breathe.

4. leave the reg sit in this pressurized condition for a few minutes. If the second stage begins freeflowing slightly immediately after you stop inhaling from it, it is most likely in need of adjustment or annual service due to improper second stage orifice adjustment or excessive LP seat wear.

If the primary or octo begins freeflowing slightly a few seconds to a few minutes after you last breathed off it, it indicates IP creep - most commonly caused by a leaking HP seat or damaged first stage orifice.

This check does basically part of what you can check with an IP gauge, it just takes longer and does not give you the same amount of information that the needle does on an IP gauge in terms of IP drop, initial swing/lockup - just IP creep over time.

5. If the reg passes number 4, turn the tank valve off but do not purge the reg. Note the SPG pressure and leaving it undisturbed come back in 5 or 10 minutes. The SPG pressure should be close to the original value. A drop of 200-400 psi is no big deal, but a large drop in pressure indicates something is leaking beyond the normal limits. If the leak is so fast you can see the needle drop just looking at it, the leak is probably large enough to warrant fixing before you dive.

Common areas for leaks are the o-rings on the hoses connecting stages and accessories to the first stage and the o-rings on the first stage plugs. These are normally easy to fix with a wrench and a suitable o-ring in a dive kit.

Other less common possibilities are the HP swivel in the end of the SPG hose, or a leak in one of the hoses. These two have the potential to get worse fairly quickly. Another even less common failure is a leak in one of the static or dynamic HP o-rings in the first stage, and this bodes ill for the health of the reg. These last three all have the potential to be bad news and it would be prudent to cancel the dive until the problem is fixed.

*Sherwood first stages use an air bleed system and a sslow leak in the first stage is normal, so they will never pass #5.

 

[Luis H]

Here is an updated check list (Rev-6). I used some of DA Aqua Masters check items with his permission.


Regulator inspection checklist

Here are a few checks that everyone is capable of doing.
Items 1, 2, and 3 are just routine inspections that should only take a few minutes.
Items 4, 5, 6, and 8 should be performed before every dive and should only take a few minutes once you establish a routine.

1. Inspect for external corrosion or physical damage to any parts including hoses. Pay particular attention to the hose to fitting interface for any signs of damage.

2. Inspect the first stage inlet filter for discoloration, particulate matter or any other signs of water intrusion.

3. Check each hose connection to see that it is at least hand tight. It is an essential check after service or reassembly and a good check to make occasionally after that.

4. Next, watertight checks are also very easy to perform and check the integrity of the second stage housing. Connect the regulator to a tank and without turning on the air (or if you have a good tight dust cap you can use that instead) draw a breath on the second stage and hold it for a few seconds. Do not draw too hard as it will collapse the exhaust valves and cause a leak. Does the regulator hold vacuum? If so, then it is probably watertight. If the regulator fails this vacuum check you probably have a leak in the exhaust valve, the diaphragm or in one of the o-rings sealing the case or through a crack in the case itself.

5. Pressurize the regulator. Depress the purge slightly. If you have to depress it more than a very slight amount before airflow starts, the lever may be improperly adjusted, reducing the working range of the valve and the flow rate of the reg.

6. Check for air leaks by putting regulator on a tank and with the pressure on, first listen to any leaks, then turn the tank valve off but do not purge the reg. Note the SPG pressure and leaving it undisturbed come back in 5 or 10 minutes. The SPG pressure should be close to the original value. A drop of 200-400 psi is no big deal, but a large drop in pressure indicates something is leaking beyond the normal limits. If the leak is so fast you can see the needle drop just looking at it, the leak is probably large enough to warrant fixing before you dive.

7. To locate a leak, the definite answer comes by submerging all parts of the regulator in a water tub or similar container. Check the first stage, the second stages, the pressure gauge, and all the hoses with special attention to all the fittings. Check around any hose connections as well as all around the first stage and out the mouthpiece of all second stages for small bubbles.

8. Leave the regulator sit in a pressurized condition for a few minutes. If the second stage begins to free flowing slightly immediately after you stop inhaling from it, it is most likely in need of adjustment or annual service due to improper second stage orifice adjustment or excessive LP seat wear.

If the primary or octopus begins free flowing slightly a few seconds to a few minutes after you last breathed off it, it indicates IP creep - most commonly caused by a leaking HP seat or damaged first stage orifice.


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.

10. Another check is the cracking pressure of each second stage. Partially fill your kitchen sink and immerse the pressurized regulator with the mouthpiece up. Air should begin to flow before the regulator gets more than 1 1/2 inches deep. If the mouthpiece is submerged before the regulator starts to flow, the cracking pressure is probably too high.

11. A tiny bit more advanced, remove second stage diaphragm cover to inspect for any corrosion, damage, sand or any other contaminants. Clean sand and contaminants as necessary. On some regulators it is very easy to open and inspect second stages, but not all. It is a good idea to learn how to open your second stage to clean it. Note: If you do not feel comfortable opening up your second stage, this step can be omitted.

These simple checks can be done by anyone. They should be done prior to any dive trip, not to mention when new out of the box or after shop service.

Check early, check often.

Some very good sources of information:
Vance Harlow's (Oxyhacker on Scuba Board and elsewhere) "SCUBA Regulator Maintenance Repair." SCUBA REGULATOR MAINTENANCE AND REPAIR by Vance Harlow
The Scuba Tools book, "Regulator Savvy" Scuba Tools

 

[maged_mmh]

6. Intermediate pressure check. Get a scuba regulator intermediate pressure gauge: Intermediate Pressure Gauge Plugs Into The BCD Quick Disconnect Hose from LeisurePro.com

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.

Just 1 Q: is that valid for both 200bar & 300bar tanks/regs?

 

[Luis H]

Just 1 Q: is that valid for both 200bar & 300bar tanks/regs?

Most regulators that I am familiar with (that includes most common brands available in the US, with one exception) use approximately the same IP (Intermediate Pressure) range of 135 +/- 10 psi (approximately 9.3 +/- 0.7 bars). The only regulator still in production that I am aware of using a higher IP is the Poseidon Cyklon regulator. The Cyklon likes an IP of around 170 psi (11.7 bars)

It should not mater if the regulator is rated for 200 bar (2900 psi) or 300 bar (4350 psi).