Robert56

iTrader: (2)

I have been getting my bottle filled at a certain speed shop. The problem I am having is air. It seems that once I get to about 6/8lbs it starts becoming pure air. Myself and the shop owner are stumped. He is definately not trying to burn me. Now this last fill, while filling, I could hear a gurgling noise coming through his n2o pump. he said oh that's normal, and no other customers have had a problem (maybe they don't notice?). Anyone have any insight on this issue, or ideas how to figure it out. I do have 15lb bottles, but have only been using one. This aso is the case when bottle is standing straight up, so I figured this takes the pick-up tube out of the picture?
Thanks, Robert

Z'mnypit

iTrader: (58)

Are they freezing it for around 45-60mins prior to filling it up?

Robert56

iTrader: (2)

No freezing, but he has no problem getting it to pressure in just a couple minutes. Where is the air coming from?
Robert

tuff

iTrader: (15)

Maybe empty your bottle and take out the valve assy and see is the orfice tube is going to the bottom of the bottle.I mount my bottle strait up and don't have any problems.But i also only use about 3 to 4 pounds and then change it out for a fresh one.I run ten pounders BTW.

1MEANGTO

I went to get my bottle filled for the first time. And it only took 4 pounds of n20 I think he did not know what he was doing though.

mrr23

iTrader: (3)

edited out my dummy portion as not to have misinformation on the boards.

at my 200 hp level i get about 4 good runs out of it. bottle weighes about 17 lbs. that's 15 lbs bottle weight and 2 lbs nitrous in my 10 lb bottle.

mrr23

iTrader: (3)

one thing i've thought about doing, but just haven't yet, is to suck the bottle to a vacuum with a vacuum pump. that way, there is absolutely no air in the bottle to begin with. a vacuum pump that would do the trick is what's used to suck AC systems down into a vacuum. i'm trying to justify the over $100.00 cost of one to do it.

the bottle is never empty. once used up, it still has air in it. just at atmospheric pressure.

gollum

iTrader: (1)

Try a new nitrous supplier.

Robert56

iTrader: (2)

The 6/8 lbs is air whether standing or in car. This last time we bled it off on scale Total bottle weight for a 15lber is 33lbs, with 15 being nitrous. I will probably try my old guy again but he takes so long. More Ideas on where the air is coming from?
Robert

860 Performance

iTrader: (1)

I would pull the bottle apart inspect the draw tube.

If you are weighing your bottles and they are around 34lbs (for a 15lb bottle) then they are definelty full. You could pump 1000psi of air into a full or empty bottle, but it wont weigh anything noticeable. Other problems Ive seen is a loose draw tube, these are the worst because it draws a mixture of vapor and liquid.
Good luck

383LQ4SS

iTrader: (33)

It has to be either gas supply contamination, pickup tube, bottle orientation, or your pressure is so low its becoming mostly gas in the bottle as it gets lower. Especially in a 15 lb bottle its important to keep that pressure up...even though it gets harder and harder as it gets lower and lower.

Do you notice a difference in performance when it get below the 6 lbs? Whats your bottle pressure like under these curcumstnaces?

383LQ4SS

iTrader: (33)

Guess i need to shake up my bottles before I make a pass each time


Who in the world told you this stuff?

mrr23

iTrader: (3)

i was wondering when you'd come in and say something about that post i made.

no one. i told myself that. think about it. why even ever purge if the oxygen doesn't seperate from the nitrogen. it's due heat. or do we purge to get the line back to liquid state? hmmm. a drop in pressure turns it from liquid to gas. what's heavier when in liquid form? oxygen or nitrogen. what temps do each turn into a liquid?

maybe i'm wrong. that's why you're here. i keep you busy.

mrr23

iTrader: (3)

another thing, why bother to have siphon tubes in bottles? or if you don't have siphon tubes, then turn the bottle upside down? come on, i need some more education. when nitrous turns from a liquid to a gas, does the oxygen then separate from the nitrogen? then gas is lighter than liquid, which rises to the top of the bottle. then we have this last 1-2 pounds if 'air' in the bottle.

mrr23

iTrader: (3)

and i said to myself last night when i made the post, someone will come in and say i guess we'll need to shake our bottles up. and to my amazement, it was you. anyone up for round 3?

mrr23

iTrader: (3)

ok my mistake on this one. it's left over nitrogen at the top of the bottle. makes sense as to why the motor goes pigrich as the bottle gets to empty.

nitrogen
boiling point -320.5F (-195.8C)

oxygen
boiling point -297.3F (-183.0C)

mrr23

iTrader: (3)

so, when pressure drops, nitrogen starts to boil first. the nitrogen gas rises to the top of the bottle while the oxygen is still in a moderately liquid state. siphon tubes are used to make sure you pull from the bottle of the bottle. where most of your liquid oxygen will be. nitrogen doesn't make the additional power when added to fuel. oxygen does. nitrogen is there to keep combustion temps down and help prevent detonation.

maybe i'm still wrong. let me do some more reading.

mrr23

iTrader: (3)

http://www.chm.bris.ac.uk/motm/n2o/n2oc.htm

At room temperature, N2O is quite unreactive with most substances, including alkali metals, halogens, and even ozone. It is therefore widely used as a propellant in aerosol cans in place of the CFCs which can damage the ozone layer. When heated sufficiently, however, N2O decomposes exothermically to N2 and O2.i'm thinking seperation here



If this reaction occurs in the combustion chamber of an automobile, 3 moles of gas would be produced from 2 moles, providing an extra boost to the piston, as well as liberating more heat. It also has a number of other benefits. The increased oxygen provides more efficient combustion of fuel, the nitrogen buffers the increased cylinder pressure controlling the combustion, and the latent heat of vaporisation of the N2O reduces the intake temperature. Therefore N2O is occasionally injected into the fuel lines of racing cars to give more power to the engine and to give the car exceptional acceleration.

mrr23

iTrader: (3)

let me add to this. his problem is having 'air' at the last 6 lbs of a 15 lbs bottle. with amount of volume of a 15lbs capacity bottle, you can't raise the temps of the bottle enough to get 6lbs to revert back to liquid. so, it's not a matter of it being 'air'. it's a matter of it being in a gaseous state to begin with. it needs to be a liquid all the way up to the solenoid. maybe that's it and not the seperation of the two chemicals. bet you no one has thought of that as being the reason, huh?

860 Performance

iTrader: (1)

MRR23,

The nitrous does not seperate into Nitrogen and O2 in the bottle. A full bottle is a mix of nitrous gas and nitrous liquid, about 99.9% liquid by weight. Think about it this way, if you had 1 small drop of liquid nitrous and you put it in your bottle at room temp and atm pressure, the small drop would boil and turn into gaseous nitrous. The nitrous gas would be in your bottle but not as liquid anymore. As it boiled and vaporized it expanded and built up some pressure in the bottle. Then if you continue to add liquid into the bottle it will too vaporize until the pressure builds up enough to lower the boiling point of the nitrous. (the higher the pressure the lower the boiling point) Once it has enough pressure to stay as liquid then the liquid builds up in the bottle.
The only time the oxy separates is at temperatures above ( I believe around 500 deg F)