All of a sudden, something's rolling around inside my tank!

[Kublai]

So just back from a dive trip off Clearwater, Florida. As I am taking my equipment out of my truck, one of my tanks now has something rolling around inside of it! Any ideas what came loose? What is the danger of the little debris damaging the inside of the tank? Tank is an AL80, just under a year old.


Great day of diving, by the way.

 

[tc]

Probably the dip tube came loose from the valve.

Safest to get it fixed before diving the tank again.

Just need to drain the tank and screw it back on, if it's close to needing a visual on the tank just get the vis done and the shop will take care of it.

 

[Kublai]

Thanks Tom for the quick, and re-assuring reply. In fact--was already taking both tanks in for an annual tomorrow morning. Bought the tanks in August 2011, and I am heading to Marathon next week- want to get it done beofre I go.

 

[vwfinatic273]

Where did you go diving in Clearwater?

 

[Kublai]

Well, off of Clearwater. . . we went to the SHERIDAN, and then after a lengthy surface interval (we cruised all over before finding a site without someone already sitting atop), we dove on an artificial reef site of bric brac/ culverts/ debris in about 40-45 feet of water NW of Honeymoon Island. It is marked by a memorial stone to Steve Hendricks, but since we were on a charter boat I cannot tell you the exact location. I am pretty certain it was not the Tarpon Springs Reef. There were a bunch of fish there, though! I have been diving a year, but this was my first Gulf dive in the local area that was not from the beach. I loved it!

 

[DA Aquamaster]

Hand tight isn't really adequate for a dip tube, they need to be tweaked just a wee bit beyond that or they can come unscrewed.

On the other hand, if I could get a customer's dip tube to unscrew at almost exactly 12 months after the last VIP, that would be perfect. Ask them how they do that.

 

[Eric Sedletzky]

Hand tight isn't really adequate for a dip tube, they need to be tweaked just a wee bit beyond that or they can come unscrewed.

On the other hand, if I could get a customer's dip tube to unscrew at almost exactly 12 months after the last VIP, that would be perfect. Ask them how they do that.

Just curious, but do you always remove and inspect the dip tube on an annual?
I've never seen a shop do this but I suppose it makes sense if there is a bunch of loose scale or chunks in the tank.
Then it also seems to me I've seen some dip tubes that are press fit, not threaded, maybe I'm imagining.
What's the normal interval for a valve service?

 

[drbill]

Tom (TC) beat me to it. Definitely something to get fixed before your next dive with that tank. I once went OOA 3 1/2 minutes into a dive (at 80 ft) when my dip tube clogged up with debris from inside the tank. Having debris fall into the dip tube (most likely from a head down descent) is like me making a swish through a basketball net from the other side of the court, but it happened. Without the dip tube in place it is a far more likely event.

 

[boulderjohn]

Tom (TC) beat me to it. Definitely something to get fixed before your next dive with that tank. I once went OOA 3 1/2 minutes into a dive (at 80 ft) when my dip tube clogged up with debris from inside the tank. Having debris fall into the dip tube (most likely from a head down descent) is like me making a swish through a basketball net from the other side of the court, but it happened. Without the dip tube in place it is a far more likely event.

A friend of mine was doing a dive in a downward angled swim through in Cozumel when one of the divers gave the OOA signal. When they got to the surface, he said that he was suddenly getting nothing but water through the regulator. On the shore they emptied the tank and pulled the valve off. There was about a lot of water in the tank, and there was no dip tube whatsoever. As soon as the diver had gone head down for the swim through, the opening to the valve had gone under water.

 

[DA Aquamaster]

Just curious, but do you always remove and inspect the dip tube on an annual?
I've never seen a shop do this but I suppose it makes sense if there is a bunch of loose scale or chunks in the tank.
Then it also seems to me I've seen some dip tubes that are press fit, not threaded, maybe I'm imagining.
What's the normal interval for a valve service?

I don't remove it for an annual VIP, but I do inspect it to ensure it is secure, since having one come loose is problematic.

If there are chances of something in the tank, it's good idea to rebuild the valve, or at least take it apart for inspection and cleaning.

Otherwise it's a good idea to rebuild the valve every 5 years when you send the tank in for hydro testing. New o-rings, washer, seat and burst disc along with an ultrasound cleaning of the metal parts will go a long way toward ensuring 5 more years of trouble free service.

For O2 service the valve will be rebuilt initially with all O2 compatible parts and lubricants and then it will get taken apart and cleaned annually there after.