How do I start a valveless?

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Mike Everman
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How do I start a valveless?

Post by Mike Everman » Thu Aug 12, 2004 5:13 pm

I'm using a stove ignition and a CM-6 sparkplug; it clicks at about 4 Hz. What's working well is to shoot an air stream right down the middle at a low rate, with the propane on low. Moving the tip closer or farther on the centerline, you should find a spot where it growls quietly. Play with keeping the growl, let it do that a few seconds, then slowly add fuel, and increase air, but only if you're varying the fuel slowly so the growl gets louder. The growl increases to the point that it gets gravelly, then loud, then you can add more of everything, moving the air straight away such that the power doesn't lessen. If it lessens, stop moving away, keep the air constant and decrease fuel a very tiny bit. At some point, you will have pulled the air away far enough for it not to make a difference and it sustains. You can increase the fuel till it gets rough, which will put it on the edge of killing. Dial it down till it gets rough in that direction, and you'll have the limits for your valve hand.

It's nice to have an air gun with a 1/4" (6mm) diameter "long" tip.

I've noticed that you've got to get a light touch on the propane. It should be easy to turn, without any sticking. It's like when you're first flying RC, you move the sticks stop-to-stop for wild upredictability, and eventually you can control with minimal movements.
Mike
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Mike Everman
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Post by Mike Everman » Fri Mar 07, 2008 3:20 pm

http://www.pulse-jets.com/phpbb2/files/ ... ll_148.wmv

Good example of a starting video for a motor that is small, without a stinger type injector.

Don't mind the sirens, they're not for me!
Mike
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Mike Everman
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Re: How do I start a valveless?

Post by Mike Everman » Mon Oct 20, 2008 7:32 pm

Another way to put it:
1. Have a spark plug and take the regulator off of your tank.
2. Start with very little fuel and very little air and see if you can get it to growl, experimenting with air nozzle position before changing the amount of air. Let it growl for a bit to warm up.
3. Increase air until it stops making noise, then back down just to where it growls again.
4. Add very little more fuel and find the new point of additional air that is just under quitting.
5. Repeat 3 and 4 until no air is needed, then crank on more fuel.
Mike
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