Recertifying nitrous bottles?

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DrCharles

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I have two 10 lb nitrous bottles (from NOS) that appear to be in perfect condition but way out of date. One I bought new in the mid-90's, filled a few times, and haven't used since then. Anyway I'll need to get them DOT-recertified before filling. I believe the stamp is good for five years.

There does not seem to be any place in southern Missouri to get it done, though. Local welding gas place doesn't. One speed shop in Springfield (still 2 hrs away) sells N2O but doesn't recertify. They might have to go to St. Louis (3.5-4 hour drive from here!)...

Any thoughts?
(Crossposted on Moparts).
 
Check with fire extinguisher recharge companies.
 
I don't understand why a welding supply could not take care of this. Here in town, there are two different companies, and at least one handles all sorts of "bottled gas" besides argon, CO2, and oxy-acetylene. I don't think they hydro-test on site. I think they are sent off to the "big plant" where ever that is

In the case of smaller bottles, I would not be suprised the hydrotest is nearly as costly as new bottles
 
I don't understand why a welding supply could not take care of this.

Welcome to rural Missouri :rolleyes:
When I get another bottle of argon/CO2 at the same store, I just put the empty one on the loading dock and they trade me for a full one (that is current stamped). They just can't handle a situation outside of their routine, apparently.
 
Welcome to rural Missouri :rolleyes:
When I get another bottle of argon/CO2 at the same store, I just put the empty one on the loading dock and they trade me for a full one (that is current stamped). They just can't handle a situation outside of their routine, apparently.
Here in rural VA I have the same problem. We had an old tractor farmers store that used to fill tanks they had just about everything helium, co2, nos, argon, oxygen etc but they went out of business and now there is nothing. We have a local welding store but they send everything off I and seriously doubt they do Nos!
 
Marmic Fire & Safety says no problem at Mtn. Home, AR (may be shipped to the headquarters in Joplin, but that's fine).

$38.50 plus tax to hydrotest each bottle, will take about a week.

Next step will be finding a place that refills nitrous bottles closer than Springfield... but one step at a time. I'm still dialing in my QFT 950 and haven't even done a full WOT launch on motor, anyway :p
 
What you probably need to consider doing is to set yourself up with a much larger "mother" bottle. There's been a lot of BS but the fact is most ANY standard pressure bottle is easy to transfer

1..Get a mother bottle and depending on the setup, arrange it for liquid transfer (for NO2)
2..Get the appropriate hose and fittings.
3...Cool the empty bottle in a freezer
4..Hook up the hoses, crack the target bottle hose end fitting and "blip" the mother bottle valve to bleed the hose.
5...Slowly open the target, then the mother valves, and transfer contents. To minimize liquid loss, after transfer, and before disconnect you have to get "gas" in the hose. If the mother cannot be easily handled/ inverted, then close the mother valve and leave the target bottle valve open a few minutes. This will allow the liquid in the hose to migrate into the bottle and vaporize into gas, anything that remains in the hose is hopefully now gas.
6...Close the target bottle valve, recheck that the mother valve is closed.
7...While filling you can "rig" the target bottle onto a scale to get some idea of where you are. You will want to first get a "tare" weight on the target bottle and to determine the filled weight. After filling, take a more accurate weight.
8...If necessary, re-chill the bottle in the freezer and top it off

It is not necessary to bleed, empty, or evacuate the target bottle unless there is reason to think it is contaminated. It IS necessary to accurately weigh bottles and to KNOW what the tare and filled weights are going to be, and leave a "fudge" (underfill) for safety

I've transferred a LOT of refrigerants, CO2, Nitrogen, and even some Argon mix gasses using this method, as well as O2 to a smaller "suitcase" Oxy-Acet outfit for portability.

You know, that bank job where we .........................
 
Thanks for the info... I will be using the nitrous so rarely that it won't pay for me to have a big bottle at home. Once the aluminum heads go on this winter, I expect to be closing in on 600 hp on motor. That can get me in enough trouble on the street.
Another 125-150 hp is just overkill unless I make it to the strip :steering:
On the other hand, when it comes to money, sex and horsepower.... too much is just right :D
 
Thanks for the info... I will be using the nitrous so rarely that it won't pay for me to have a big bottle at home. Once the aluminum heads go on this winter, I expect to be closing in on 600 hp on motor. That can get me in enough trouble on the street.
Another 125-150 hp is just overkill unless I make it to the strip :steering:
On the other hand, when it comes to money, sex and horsepower.... too much is just right :D


Once you go on the hose...
 
I'm going to be restrained, since my short block is built with KB280 hypereutectic pistons. They're much more sensitive to detonation than forgings and I'd like to keep them out of the oil pan (or headers). :eek:
Also the Powershot solenoids have a small orifice that can only flow so much anyway.
I put a single Fogger nozzle on my old BMW 745i (factory turbo) with 40 hp jetting, just to spool the autobahn-sized turbo quicker. Even with that small system, I could empty a 10 lb bottle in one weekend... $36 in the mid-1990's. Probably $50-60 now :realcrazy:
 
Bottles are recertified (and a really old flea-market 5-lb CO2 extinguisher too, had it recharged once it passed). Just have to go pick them up tomorrow :)

Now... what are people paying for nitrous oxide these days? There is only one speed shop in my town and they want $75.00 to fill each 10-lb bottle! :mad:

I know prices have gone up since the last time I paid $35 (admittedly 25 years ago) but that seems awfully high. :realcrazy:

And the local Airgas will only sell me a 50 lb bottle, even though the corporate website says they will refill cylinders as small as 6 lb. :icon_fU:
 
Found a place in Mountain Home that filled them up for $65 (no tax) per 10 lb bottle. He even went over to Marmic and picked them up :)
This should be entertaining... :steering:
 
a homebrew place by my house hydrotests CO2 bottles for $15/bottle, check those places out. What pressure does a NO2 run at? May be a little different. I sold 2 out of date 20lb bottles for $40. "Property of PEPSICO" oops.....10 years out of date, Im sure they didnt miss them.
 
I'd check them out, but the cost of traveling to California would wipe out any savings :p
Working pressure in a nitrous bottle is 900-1000 psi. I think they are hydrotested at 3000 psi? Anyway it's all taken care of :)
 
Looks like I got ripped off. I weighed the spare bottle, clearly marked on the original NOS label as 24 lb, 12 oz when full with 10 lb.
On my digital postal scale it only weighs 21 lb 10 oz! So there's only 7 lb in it.
The one in the car is 24 lb 4 oz, so he "only" shorted me half a pound on that one.
Guess who's getting a call tomorrow... :mad:
And the credit card company if he doesn't have the right answers. I'm doing a chargeback for 3.5 lb at 6.50/lb. Doesn't ANYONE do the job they're getting paid for any more?? :(
 
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Looks like I got ripped off. I weighed the spare bottle, clearly marked on the original NOS label as 24 lb, 12 oz when full with 10 lb.
On my digital postal scale it only weighs 21 lb 10 oz! So there's only 7 lb in it.
The one in the car is 24 lb 4 oz, so he "only" shorted me half a pound on that one.
Guess who's getting a call tomorrow... :mad:
And the credit card company if he doesn't have the right answers. I'm doing a chargeback for 3.5 lb at 6.50/lb. Doesn't ANYONE do the job they're getting paid for any more?? :(


Depends on the filling station. Sometimes they can’t get the filled cylinder full. If they charged you for product you didn’t get that’s a different story.
 
Depends on the filling station. Sometimes they can’t get the filled cylinder full. If they charged you for product you didn’t get that’s a different story.
I paid $130 ($65 for each filled 10 lb bottle). I received 9.5 lb in one, and 7 lb in the other identical bottle done at the same time with the same pump. So it's the different story, unfortunately.
At least it was only at worst a $22.75 lesson on where not to go again.
 
Finally got past the holidays, a recurrence of my ulcer, AND a root canal! So yesterday afternoon... drove 40 miles to the shop who'd underfilled my nitrous bottles. Actually to his home/garage where he keeps the mother bottle. Turns out he's a well-known racer on one of the Street Outlaws TV shows.

He tried to blow even more smoke up my *** that "once you crack the valve [which I hadn't] you can easily lose three pounds", bottles are full at 24 lbs (clearly marked 24 lb, 12 oz on the labels by NOS), and his scale was in metric because "Nitrous is always sold that way". In 40 years of wrench turning I've never heard it in anything but pounds.:rolleyes:

Anyway I got 3 lb added to the bottle with 7 lb in it. I hope. Feels the same as the other one now. The other one is only about 1/2 lb short, and I hadn't had room in the freezer for both (he won't even use a pump, just freeze the receiver bottle) so he wouldn't top it off.

Claims he's been selling nitrous since 1993. I wonder how many have been shorted besides me... Anyway I know who NOT to do business with again. I wouldn't buy a glass of water from this guy if my hair was on fire. My ulcer doesn't want me to think about this any more.
 
Seems to me in the long run you could do well to buy yourself a mother bottle. Hell maybe you could sell a little to the locals
 
If I find that I'm using more than those two 10 lb bottles this year, I'll look into it :) But I doubt I will use it very often - there is no shortage of power on motor alone!
:steering:
 
Long time ago (early 2000's) I got shorted twice buy a guy that I bought nitrous from regularly. First time I just let it go (missing about 2 lbs). After that I started taking my bathroom scale with me....next time it happened was the last time I purchased nitrous from him.
 
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