New tank/valve

[scubajohn921]

So I ordered a 30CF pony from ST here on the board, it came today with the valve very loose and empty (for shipping) my question is, is there a special procedure for tightening that valve up?

 

[robzr]

Not really, make sure the threads are clean, make sure the surface that the o-ring will seat on (on both the tank & the valve) is clean. Make sure the dip tube is tightly threaded in the valve (stick that sticks out the bottom of the valve). You may want to put a tiny bit of silicon lube on the valve threads and a real thin coating on the o-ring. Then thread it together, you can tighten it by banging on the valve knob a little with your palm (not too hard, you just want to snug it a little, but not so much you are bending the valve stem or making it hard to get off). Don't worry as long as its snugged a bit, the air pressure is not going to shoot the valve off

Oh and of course since it's been taken apart, you technically need a visual inspection done on it. If it already has a sticker you might find a nice guy at a shop to do it for free.

Rob

 

[captndale]

1. Make sure that the dip tube is tightly screwed into the valve. If not, tighten it with a pair of pliers.
2. smear a little bit of Kristo Lube on the valve threads. Do not lubricate the o-ring.
3. Thread the valve into the tank as far as you can by hand.
4. With a calibrated rubber mallet give the valve a rap with exactly 5 ft-lbs of energy.

 

[pescador775]

The O ring needs a little dab of grease to help it deform to the correct shape. Tightening the valve is a topic which brings out a lot of comments. You can wrap the cylinder with newspaper and clamp in a vise. Use a wrench to snug the valve until it stops turning. This should equal about 30 lb-ft of torque. The valve will accept up to twice that torque without problems so don't worry about hurting it. If no vise, get a buddy to grip the tank as tight as he can. Dive shops use the back hand, clubs or whatever to screw the valve in place. This is because it is easy to remove later without tools. In fact, if the tank is drained the valve will almost fall out. However, it might be better to squeeze as much air as possible from between the mating surfaces due to possibility of corrosion and this requires a firm tightening.