Regulator won't seat properly

[MrVegas]

I have a yoke regulator that hisses when attached to the valve. Obviously, my first reaction was to change the tank o-ring, but that didn't make a difference and other regulators worked fine on the tank. The regulator at issue appears to have a small air leak at the seat when attached to other tanks too. This is a development as of this summer. (Regulator has been used for several years and serviced over the winter. The problem occurred the first time hooked up this summer.) My guess is that it is probably actually not so bad as to not be diveable for easy rec dives, but I don't really want a regulator with bubbles coming out from the seat.

There does appear to be a very, very small nick on the yoke where it attaches to the tank, but it is tiny and does not go all the way across the ring. Any thoughts on what is going on or how to fix this? (It is a Sea Elite Covert. I know it's a cheap reg, but these have worked well for me for years.)

 

[Zef]

If you are fairly certain the leak is at the 1st stage to tank valve interface, you can polish out the nick on the face of the 1st stage attachment with some fine grit sand paper. Put the paper on a flat surface and gently circle your regulator on it. Use progressively higher grit (e.g., 280, 500, 600).

-Z

 

[Nemrod]

The nick is probably the cause of the leak. Chrome plating is very hard and you may or may not be able to polish it. Usually where there is an indentation in metal then to either side there will also be a slight bulge. If the chrome plating is peeling the leak can actually be between the plains and the brass, I have encountered that at times. Just peel the loose chrome away if such is the case.

Make sure that the nozzle assembly, assuming that this regulator has a removable assembly, is tight into the first stage body.

 

[lexvil]

The part that goes against the o ring holds the yoke on, are you sure that is tight, also pull out the HP post plugs and check those o rings.

 

[johndiver999]

Also check that the yoke is not bent and the regulator is sitting squarely on the valve. A tank falling over can bend the yoke and cause a failure to seat.

 

[Germie]

And change yoke to DIN will also solve most problems. Here almost nobody dives yoke anymore. For most regulators you can buy conversion kits.

 

[Nemrod]

And change yoke to DIN will also solve most problems. Here almost nobody dives yoke anymore. For most regulators you can buy conversion kits.

Sometimes in the Caribbean, you pick the tanks that leaks the least. And there may not be any DIN tanks or convertible valves and if there are they may cost extra or the threads so corroded or deformed that installing a DIN fitting is impossible. A clamps tolerate a lot of abuse and DIN has it's own issues. Yes, DIN is better but often not available. Depends upon where the OP is diving. A clamp converters are less than ideal emphasizing the bad attributes of both systems and little of the good.

 

[divad]

And change yoke to DIN will also solve most problems. Here almost nobody dives yoke anymore. For most regulators you can buy conversion kits.

What is this "Yoke" you speak of.....?

 

[Germie]

INT is the name we use here. Haha. I live in Europe, so most divers here use the Deutsche Industrie Norm, DIN.

And if there are not INT tanks, an easy convertor from DIN to INT is available. I have never used INT regulators. And the reason technical divers only use DIN is that it is stronger, less chances of leaks, etc.
I never have been to places where I needed a convertor. Bonaire, Curacao, Mexico, Thailand, Europe, always you could choose between DIN and INT tanks.
I know there are valves that cannot be converted because there is no insert option. But I have only see them on really old tanks. For filling they use here also both systems.

And of course, also DIN can leak, there is also an o-ring between first stage and valve. But not 2 anymore.

 

[Dan]

I had similar problem that finally got so bad in the middle of deep dive that I had to thumb the dive. See my story in my trip, below:

Tuna Wreck, Similan

Dove Tuna Wreck in Similan (Island 5) on 31 January, 2023. Sandy bottom was at 38 m. Top of the wreck (starboard side) was at 31 m.

scubaboard.com

Most Scuba tank valves, nowadays can fit with DIN connector. In fact, to use the tank for Yoke connector, you have to put an inch long cylinder with 3/4” deep machine screw insert with 2 O-rings sitting in grooves on both side of the insert, as shown in Figure 1, below.

Figure 1, Scuba tank insert, courtesy of
So, you’ll end up having 2 seals (2 sets of metal seal faces and O-rings).

My problem was the rough handling of the operator during filling up the tank and aligning the metal seal face in the yoke adapter to the O-ring insert inside the tank valve. They tend to do it in a hurry in filling up the tank and putting the regulator back to the tank valve for the next dive.

The yoke 1st stage metal sealing face is exposed like a sore thumb. If you are not careful in removing the 1st stage regulator off the tank valve, that metal seal face can get easily scratch, banged up, as shown in Figure 2, below. Alignment of the seal face can easily miss as there is only 1/8” (3mm) raised ring metal seal to slide the seal ring into the O-ring insert in tank valve. Mine got so bad that the scratch was actually cut the O-ring insert in the tank valve.

Figure 2, Badly scratched up Seal face of my Yoke connector in the 1st Stage Regulator.


My solution is to get rid of the Yoke connector and replace it with DIN. Problem solved!

Why? Because the metal sealing surface is now an inch deep inside the tank valve protected by the machine screw hole. The O-ring is now on the 1st stage regulator that you can inspect and replace more easily, as shown in Figure 3, below.

Figure 3, DIN connector of my 1st stage Regulator.


The operator will be more aware about not to bump the soft O-ring to hard object for obvious reason. Square alignment of the seal face in the tank valve with the O-ring on the DIN connector will easily be made by screwing the 3/4” deep machine screw DIN adapter into the tank valve.

You also get rid of the insert and another O-ring seal in the tank valve, hence, less prone to leak as you have only 1 set of seal instead of 2. Another advantage is you get rid of that heavy, clunky yoke, which I never understand why we have it. It’s simply a bad design.

My recommendation is:

Covert your Yoke to DIN connector!