check valve for syringe fueling

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shiny455
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Sat May 28, 2011 5:55 pm

i've had a pvc combustion for about a year now and it was originally a spray and pray but ive decided to use a syringe to fuel it. i got the syringe, butane and figured out the amount of butane needed. its a 7.6L chamber i think but i only got a 80ml syringe so i need to fill it three times and i want a check valve in the gun to stop a flame coming out the hole i inject the fuel into, as I have burnt myself before with the same thing. what's the easiest way i will be able to do this.
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Technician1002
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Sat May 28, 2011 7:08 pm

A small flap of innertube screwed down next to the hole works fine.

It would be spoon feeding to give more detail.
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shiny455
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Sat May 28, 2011 7:33 pm

ok thanks i was thinking something like that but i thought inner tube would burn
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Technician1002
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Sun May 29, 2011 12:28 am

Why would rubber burn and PVC not? It will be fine if it seals the hole. Without an exposed hole, the jet won't form.
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jimmy101
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Sun May 29, 2011 3:45 pm

COuple things that work well.

1. Install a schrader valve and then remove (permanently) the stem. A syringe needle fits through the valve body easily and the plastic screw-on cap is more than adequate to seal a 1x gun.

2. Don't worry about it at all. Just use a long needle, lift the clean out cap a fraction of an inch, insert the needle and inject. Repeat as needed. The amount of fuel lost won't be enough to make a difference.
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