Question about putting tanks and valves together!

[Florabama]

I just bought two Steel 108s from Scuba.Com. They came with the valves in a seperate box and the valve tube disassembled from the valve. While I've taken valves off of tanks many times, I've never put new valves on new tanks before.

Should I add a little silicone to the O-Ring, ,valve threads and to the valve tube, and does the valve tube just screw into the bottom of the valve? Before putting them together, just thought I would ask for any available advice from the experts.

 

[jhelmuth]

If there's a nice sheen on the existing o-ring, you shouldn't have to "lube" it (it's lubed already). But since it's so easy to do so now, why not go ahead and do it anyway? If you have Crysto lube, use it and replace the stock o-ring with a viton type of same size (if readily available) - otherwise just use the stock o-ring with some silicone grease (just a thin film).

 

[oversea]

Screw the little tube in from the bottom and the screw the valve in good and snug, but hand tight. Use no lube as it could contaminate your air. Don't use a wreck to tighten the valve. I have emptied tanks with factory installed valves and once pressure was relieved the unscrewed by hand.

 

[pants!]

Will your dive shop fill an empty tank? Most shops, I believe, will insist on performing a visual inspection on any tank brought in with no pressure inside.

 

[Mark Vlahos]

I just bought two Steel 108s from Scuba.Com. They came with the valves in a seperate box and the valve tube disassembled from the valve. While I've taken valves off of tanks many times, I've never put new valves on new tanks before.

Should I add a little silicone to the O-Ring, ,valve threads and to the valve tube, and does the valve tube just screw into the bottom of the valve? Before putting them together, just thought I would ask for any available advice from the experts.

Personally my tanks are O2 clean for partial pressure NITROX blending, so silicone is not a good choice for lubricating anything in my case, I use Cristolube. You do not need to lubricate anything for the valve to seal properly. The O ring should seal without any extra goop. Many people use some lubricant on the threads to keep the mechanical connection in good shape, this is about not stripping the threads or damaging the threads themselves not sealing the valve to the cylinder.

You really don't want to use any oil or similar substance to lubricate any of the connections. When you put the dip tube (the "valve tube" you spoke of earlier) make sure that if you use pliers that those pliers do not have oil or grease on them and try not to bend or break the tube.

Best of luck,

Mark Vlahos

 

[cerich]

Use cristolube only on the oring and not much, use a clean wrench to snug up the tube without stripping the chrome off. Otherwise your tank will end up sounding like a rattle. I just give the handle of the valve a smack with my palm to tighten, no rubber mallet needed here at all!

 

[Florabama]

Thanks all! Excellent advice as ususal. I am so sorry I didn't find Scuba Board sooner. It is such a great resource with all the experience and expertise represented here.

Good point on making the tanks O2 clean. I will get some crystalube. Any leads on a good online source?

 

[pants!]

Using christolube won't make your tanks clean.. they need to be O2 cleaned and the valve and main O-ring need to be O2 clean and O2 compatible.

 

[Florabama]

Using christolube won't make your tanks clean.. they need to be O2 cleaned and the valve and main O-ring need to be O2 clean and O2 compatible.

Thanks! What's involved with O2 cleaning?

 

[Mark Vlahos]

Thanks! What's involved with O2 cleaning?

First... Are you certified to use NITROX? If the answer is no, then you don't need to have your tanks O2 clean. Save your money.

Second... If you are NITROX certified, do you get NITROX fills at a shop that uses the "Partial Pressure" method for blending. If the answer is no, then you don't need to have your tanks O2 clean. Save your money.

Third... If you are NITROX certified and the shop where you get NITROX fills does use the "Partial Pressure" method for blending then you DO need to have your tanks O2 cleaned. If your answer is yes to this question, then you should take the tanks to the shop that does your NITROX fills and have them do what is necessary to see to it that your tanks are properly cleaned. This will cost you some extra money, but it is necessary for the safety of the person who fills your tanks.

Since you have asked the question in the first place I am guessing that you will most likely not be a candidate for having your tanks O2 cleaned.

Mark Vlahos