Buying used tanks

[Frackingawesome]

Hey guys,

I am looking at buying 4 used tanks from a guy I kinda know. these are old tanks (some from the 90s I think) that have not been used in years, I am hoping you guys can give me some advice on what to look for/avoid in these tanks. I don't mind taking the valve off and looking inside but I don't know what to look for... I would replace all the valves with newer ones so the DIN valves are not an issue. they are super cheap so I would really like to get them if possible...

the tanks
2 x Two 80 cu ft Sherwood steel scuba tanks(yellow below) - for my wife...
2 x Sherwood Genesis 100 galvanized (silver below) - would be put in a twin set...

 

[al303]

If I had to guess, those are PST tanks. 3500 psi so you have to keep the DIN valves. Only the newer 3442 psi tanks can you use a Pro valve with a spin out insert. If they pass hydro, they would be great tanks.

 

[snowdog61]

Those look to be 7/8" necks - not the newer standard 3/4". If they are the HP 3500psi then you are stuck with using the DIN valve as you can't simply put an insert in as the 3500 valve is threaded deeper and pretty sure there isn't 7/8" HP yoke.

 

[rhwestfall]

yep, what was said above... likely 7/8", and are 300 BAR DIN.

 

[JackD342]

Check inside for rust, corrosion, and pitting. Rust may not indicate they will fail a visual inspection, but at least you will know if you are likely to need them tumbled. If there are any pits and gouges, that is more likely to get them condemned.

Check the outside for the same, and especially take the plastic boots off and find out what is going on under those.

 

[W W Meixner]

Hey guys,

I am looking at buying 4 used tanks from a guy I kinda know. these are old tanks (some from the 90s I think) that have not been used in years, I am hoping you guys can give me some advice on what to look for/avoid in these tanks. I don't mind taking the valve off and looking inside but I don't know what to look for... I would replace all the valves with newer ones so the DIN valves are not an issue. they are super cheap so I would really like to get them if possible...

the tanks
2 x Two 80 cu ft Sherwood steel scuba tanks(yellow below) - for my wife...
2 x Sherwood Genesis 100 galvanized (silver below) - would be put in a twin set...
View attachment 531353 View attachment 531354 View attachment 531355

FA...

Pass on these...uncommon Sherwwod thread size...

New standard valves/standard doubles valve sets...will not fit...

Check-out Dive Gear Express...new cylinders are not expensive...and you know what you're buying...

By the time you have the old Sherwood valves rebuilt...the cylinders VIP'd/re-hydro'd...and possibly O2 cleaned...and that's assuming all four pass...you will have far more invested than the cylinders are worth...

Walk away...

Best...

Warren

 

[rhwestfall]

BTW - you can get new (costly) valves, but they too will be 300 BAR

XS Scuba Valve - 7/8 x 14 UNF inlet Threads - 300 bar DIN 4350 psi AIR

 

[Bob DBF]

Those look to be 7/8" necks - not the newer standard 3/4".

Actually the 3/4 standard had been around quite a while. The newer 7/8 standard was made by DOT for cylinders 3500# and over, restricting the connection to 300 bar DIN.

If the OP has a good relationship with his LDS, he can probably get them to help evaluate the condition.

The downside of the tanks is having to have a 300 bar DIN reg. Personally, I'd pick them up if the price was right, but I'm just an old tank whore.



Bob

 

[Barnaby'sDad]

If at or close to the price of “on the house” I’d take them, run them to the LDS, and see if they can be put into service for a reasonable price.

 

[happy-diver]

Perfect!

and when cleaned up even more perfect

Rechrome?