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Old 02-19-2008, 09:05 AM
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flygilmore
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Default Kill switch help

Hello, I am wanting to hook up two kill switches for my mag. G26. I plan on having a manual switch and a servo operated switch. I plan on using the heavy duty slide switches from Radio Shack as they come two in a pack. Each switch has two terminals and I wanted to check to see if my plan for hooking them up is correct.

From what I understand, I need to run a wire coming from the black wire of the motor to the first terminal of the first switch, then run a wire from the second terminal of switch #1 to first terminal of switch #2 and then a wire from terminal #2 to a ground on the motor. I know that this sounds kind of confusing but is this the correct method for installing these two switches?

Thanks for your help!
Old 02-19-2008, 09:55 AM
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Default RE: Kill switch help

Nope.

That wire grounds the ignition - which prevents the electricity from jumping the gap in the spark plug. So in a one-switch setup, the switch must be closed (ON) for the engine to QUIT - which is backward from the way you would normally think.

You are talking about hooking them up in series. In series, they must both be closed (ON) for the engine to quit.

You want them set up so that if EITHER one is closed the engine will quit - so you want them set up in parallel
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Old 02-19-2008, 11:58 AM
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flygilmore
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Default RE: Kill switch help

Thanks for the pic, that helps. So, in parallel, both switches must be on to run the motor but only one must be turned off to kill the engine? That is what I am after if that is the case which I am sure it is.

thanks.

Just recieved a PM from someone who is now saying that the series connection is what I want as I originally thought-can someone who has this setup please confirm which is correct.
Old 02-19-2008, 02:12 PM
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Default RE: Kill switch help

The parallel setup as Minnflyer described is correct for a magneto kill switch. The series setup is correct if you have an electronic ignition setup.

In the parallel setup, EITHER switch by itself (closed) can kill the engine, but BOTH have to be open for the engine to run.

In a series setup, Either switch can also kill the engine by itself (open); the difference is that you're cutting off power to the ignition module when you open one switch, whereas on a magneto, you're grounding the current from the mag when you close the switch.
Old 02-19-2008, 02:20 PM
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Default RE: Kill switch help

On the G-26, if you ground that wire the engine stops.

So if you CLOSE the switch (which puts the switch in the "ON" position) the ignition is OFF

Two switches in Series means BOTH switches must be closed (ON) to turn the ignition OFF

Two switches in Parallel means that if EITHER switch is closed (ON) the ignition is OFF
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Old 02-19-2008, 03:19 PM
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flygilmore
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Default RE: Kill switch help

So, what Minnflyer is saying is that when I get my Radio Shack switches, for my magneto G26, the switches will need to be switched to the "OFF" position to allow the motor to run and only one will have to be switched to the "ON" position to kill the engine?? Sorry for all the questions but this is a first hooking up a mag. kill switch using my own wiring harness and switches.

Thanks a bunch!
Old 02-19-2008, 03:23 PM
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Default RE: Kill switch help

Now you got it.

The confusing part is that it is backward. Usually, you turn a switch ON to make something work, but in this case you turn it ON to close the circuit that grounds the magneto and prevents a spark - which shuts the ignition OFF
Old 02-19-2008, 04:48 PM
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Default RE: Kill switch help

For an electronic ignition, why wouldn't you have it exactly the other way around?

Wired so that current is carried from the battery to the switch only when both switches are turned ON...

Old 02-19-2008, 04:50 PM
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Default RE: Kill switch help

For an electronic ignition, you WOULD have it the other way
Old 02-19-2008, 05:16 PM
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Default RE: Kill switch help


ORIGINAL: MinnFlyer

For an electronic ignition, you WOULD have it the other way
Thanks. I just finished setting up a EI gasser this way and I decided to read about kill switches.

The posts made me a bit nervous about my setup.


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