Question about my new steel tank (new to me).

[scubadada]

Was the J valve a Scubapro adjustable reserve with built in gage?

It was purchased as a Scubapro cylinder and valve but was not adjustable and had no built in gauge.

 

[AfterDark]

Poppycock!

Your opinion.

 

[rnln]

Do you open your valves all the way without backing off a bit? That'll wear the seat for sure.

I usually back it off a bit, on anything, when is't a little tight. On this tank, I did the first time as a habit but I don't think I did every time. I open it up to test it at least 4 or 5 times total.

 

[James79]

thanks everyone.

James, Thanks. I will measure it in a while and post. This weekends, I will get on my feet and do the tuning, then take it off so you can see it in detail

grf88,
I will do that.

Thanks.

I wouldn't pull the valve until you're ready to get it hydro'd... Not just to get max use out of the fill, but also to keep moisture and contaminants out. Then I would have the shop take a quick look in it before it went to hydro (if they see an obvious reason the vis would fail, no reason to pay for the Hydro).
Of course, my advise is always worth what you payed for it! Lol
James

 

[AfterDark]

It was purchased as a Scubapro cylinder and valve but was not adjustable and had no built in gauge.

The only valve that I've in 50 years that needed service was SP J with the gage. Since SP doesn't offer the part needed to service it they are paper weights these days.

 

[rnln]

I understand. Thanks.

 

[grf88]

Your opinion.

One of many articles why it is a bad idea:
The Quarter Turn That Kills - Cave Diver Harry

Also there is no way you can damage the seat of a scuba valve by opening it all the way.

 

[AfterDark]

I usually back it off a bit, on anything, when is't a little tight. On this tank, I did the first time as a habit but I don't think I did every time. I open it up to test it at least 4 or 5 times total.

I've worked with all manner of HP valves in my life time. I was formerly trained in their use by Electric Boat and one of the things was to never keep the valve opened on the seat, because it caused seat wear. My diving instructor years before that instructed us the same thing for the same reason. I even back my outside faucets a bit, my shut off valve for the bathroom backed off a bit. There's no downside unless you let some monkey tamper with your gear.

 

[AfterDark]

One of many articles why it is a bad idea:
The Quarter Turn That Kills - Cave Diver Harry

Also there is no way you can damage the seat of a scuba valve by opening it all the way.

Yeah the 1/4 turn is BS less than 1/16 is all that's needed. Opening all the way then backing it off a bit isn't not opening full the air flow isn't impacted one bit unlike the stupid 1/4 turn.

Evidently the divers in that article didn't need a monkey to tamper with their gear, they were the monkeys. Human error not a hardware problem.

 

[grf88]

I've worked with all manner of HP valves in my life time. I was formerly trained in their use by Electric Boat and one of the things was to never keep the valve opened on the seat, because it caused seat wear. My diving instructor years before that instructed us the same thing for the same reason. I even back my outside faucets a bit, my shut off valve for the bathroom backed off a bit. There's no downside unless you let some monkey tamper with your gear.

Please point out how having it all the way open can possibly damage the seat:

Maybe it will place a little more stress on the O-ring on the stem but on most scuba valves they have now been replaced with an extra Teflon washer.