I am brainstorming about the possibility of buying the required equipment to properly refill the small CO2 [10oz] bottles we employ for shifting and throttle control.

Other than the "mother" bottle, what else is required and who sells the items?

The guy who fills mine just has the two fittings, hard line between them and a ball valve. Probably better though to at least have a pressure gauge so you would know how much is in the small bottle.

Back before my husband had an on board compressor we would fill his bottle at a paintball place.
So, you might want to check out some of this equipment.....

https://www.ebay.com/bhp/paintball-fill-station

larry pumps and scales to my knowlege to do it right.i always did bottle to bottle and would chill the little bottle first and open big bottle first.i dont think you can overfill that way but maybe so.the on on board compressor is well worth the expense.

This message has been edited. Last edited by: rusty,

I just have the fittings and hose to connect to my mother bottle. Chill the small one, connect them and open each valve. Open mother valve slowly. Let pressure equalize and done. Just weigh the bottle before and after. No prob doing this at all.

Big bottle, little bottle and a scale.

you need 2 "CGA 320" fittings and a 3000 psi hydraulic hose with 1/4 NPT fittings. I also have a ball valve installed in line.

I don't worry about getting the bottle completely full because it takes about 3 mins from start to finish to fill it. I don't weight it, I don't chill it, i don't even take it out of the car. So if it gets 8oz in it instead of 10, I will fill it 2 weeks earlier next time.

Joe

quote:

Originally posted by Coloradoracer:
I just have the fittings and hose to connect to my mother bottle. Chill the small one, connect them and open each valve. Open mother valve slowly. Let pressure equalize and done. Just weigh the bottle before and after. No prob doing this at all.

This how I have done mine for a long time.
One time I left a little more than 10oz in the bottle.
The car was sitting in the sun, in the lanes and blew the burst disc.

This message has been edited. Last edited by: SGDCXCVI,

I’ve never filled my C02 bottles with a scale and never did a pre-chill of the bottle. Coming out of my mother bottle i have a ball Valve into a “Tee.” One leg off the tee has the fitting to attach to the little C02 bottle. The other leg (pointed straight up) had another ball valve open to the atmosphere. Starting with both ball valves closed, i connect my 10oz bottle and open the screw valve. Next i open the screw valve on the mother bottle. Then quickly open the ball valve coming out of the mother bottle to put C02 in little bottle. I then immediate close back that same ball valve and open the one to the atmosphere to dump the contents of the little bottle. This causes the bottle to chill itself. Close the atmosphere ball valve and open the mother bottle ball valve to refill the Small bottle. Level it open for a minute or two the close everything and you are good go. Yeah you loose a little C02 each fill but it only takes a couple minutes to fill without it being a complicated process. Just make sure you use fittings rated for the high pressure.

Someone has the line and fittings for sale on Dragraceresults classifieds Facebook page.

I cheated!! We keep cylinders of nitrogen at work. Robbed the bottle fitting off an old CO2 regulator that was shot, adapted it to a 1/4” refrigeration flare, and use a refrigerant hose to charge up my bottle. I regulate the pressure while filling with the regulator on the nitrogen bottle. Usually put around 500-600 psi in my “C02” bottle, it lasts a few races pretty easily. If it gets low, it only takes 2-3 minutes start to finish to get the nitrogen cylinder out of the trailer, hook it up to the c02 bottle in the car, and re-fill it. Cheap, simple, and works very well!

Have you thought about going to the on board air compressor? Lots of good pre-made systems you can buy or can build one yourself for around half the price or so.. I never wanted to put an SLE on my car because did,'t want to have the possibility of running out of CO2 or buy a $400-$500 pre made system.. Then I stumbled across a couple forum posts about how to build it yourself and it was super simple..

quote:

Originally posted by Iforgot:
I cheated!! We keep cylinders of nitrogen at work. Robbed the bottle fitting off an old CO2 regulator that was shot, adapted it to a 1/4” refrigeration flare, and use a refrigerant hose to charge up my bottle. I regulate the pressure while filling with the regulator on the nitrogen bottle. Usually put around 500-600 psi in my “C02” bottle, it lasts a few races pretty easily. If it gets low, it only takes 2-3 minutes start to finish to get the nitrogen cylinder out of the trailer, hook it up to the c02 bottle in the car, and re-fill it. Cheap, simple, and works very well!

My only concern with using nitrogen is in a door car, in an accident if you filled the cabin with N2 even briefly, it could be game over for the driver. Even one breath can be enough for suffocation. CO2 does displace oxygen, but does not have the same suffocation affect on the body.

I have a 20lb bottle and the hose with the coupler for the small bottles. 99% of the small bottles weigh 2 lbs 2 oz. when you put them on the scale empty. Freeze the small bottle. Once I bleed the air. I open the small bottle valve & fill to 2 lbs 12 oz. Done. The scale the hose & the mother bottle.

I must be low tech kind of guy.

Been refilling the small bottle from the large bottle almost 20 years now.

We have the female to female hose, I tip the mother bottle upside down, open both valves, let them even out for a few seconds and its done.

If I am doing it wrong, it works doing it wrong.

If you ask for a mother bottle with a dip hose in it, you don't have to tip the mother bottle when filling.
If I fill at ambient temperature , and put the small bottle in the car, when it warms, it often will knock the burst disk out of it. I have found that this is often more the case when I have a more empty bottle, and I cheat the little one full by freezing it before filling. The warming really shoots the pressure up. So I avoid cheating fills now. I did one with a pretty empty mother, and cheated it. Gave it to a friend in his shop, and an hour later they about shat themselves when the burst disk let go.

Our bottle is in a confined area between the blow shield and the radiator. Likely the warmest spot on the car.
Racing many days over 100 degrees.
In all these years have never had one pop the disc.
Maybe just dumb luck.
But that's the way we do it.

this is what i use, the large tank has a dip tube in it, i only check the wieght after filling and its usually less than full. when i fill i will open the small bottle and let some c02 in, then close the valve at the large bottle and vent the little bottle quick and that will cool the small bottle, then i will fill the small bottle. never had an issue and works fine for me.