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Lit Starter Button and Mag Switches

Flying Canuck

Well Known Member
Patron
An earlier classified for an ACS keyed ignition switch got me thinking. That item becomes available when people convert to a push button start setup, so I thought, why don't I look into that. So I came up with the simple approach in my head and then I thought about extensions to that. No idea if I'd actually do this, but here goes.

I have a VP-X Sport which has a starter output that currently goes into the ignition switch (BATT). This voltage is passed to the S post (on switch and starter contactor) when the key is in the start position. The VP-X will turn this circuit off if it sees that the engine is running. So..

L and R mag toggle switches (upside down so 'ON' grounds the magnetos)
Starter circuit from VP-X goes to hidden enable switch then to an illuminated push button that is wired to always be on (based on this starter circuit). This would illuminate the button when the master is on and the engine is not running. Simple, right?

Now comes the idea. If I wanted the button to only light up when one of the mag switches was 'On' (which is actually off), how would I do that? This would essentially act as a hot mag light when the master is on. Make sense? It would be easy if the mag toggles weren't upside down, use DPST toggles and wire the starter circuit in parallel across one pole on both toggles. Doesn't work in this case.

I know, simple is better, but I think this would be a great feature if it could be done without adding too much complexity. And yes, I'm aware that this wouldn't warn me about a hot mag if my master is off. It's still going to be inferior to the removed key protection that you get with the keyed ignition switch.

EDIT: Would a DPDT On-On switch work? The schematic I just looked at connects pin 2 and 5 to pins 3 and 6 respectively when toggle is down and to 1 and 4 respectively when the toggle is up. So connect p-lead to 2, ground to 1 and starter circuit to 5 and connection to push button to 4. I think that does it. Thoughts?
 
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Switch

I did my Rv-10 similar to this. The led ring light around the pushbutton is only illuminated when there is power from the. Vpx AND the key switch for the bus manager (ignition, injectors, ECUs) is on.
 
Just saw someone in another thread mention that the ACS ignition switch disables the left mag when starting if you have the jumper wired (which you should if you have a right mag with impulse coupling). I'm fairly sure that this is how I am configured - with 2 regular mags.

This raises a question of starting procedure with mag toggle switches. Should the start button be pressed with just the right magneto on, and then follow by turning on the left magneto? What about doing a mag check, anything different about that?

I decided to make this change and have the parts on order, I just wanted to be sure I knew what I was doing.
 
Standard......... is impulse mag is on the LEFT (pilots side) of the motor. You start with only that mag on. After start, you turn on the RIGHT non impulse mag.
 
Thanks for catching that. I took that from the other post, just looked at the ACS instructions and see that it is definitely the LEFT mag that's the impulse coupler. Start process makes complete sense.
 
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