Does anyone know how to wire 4 post keyswitch to a briggs and stratton 18hp twin?
ASSUMING the engine has a "self-powered" ignition system the first rule is to use the proper ignition switch that grounds out the ignition system to "kill" the engine, and NEVER puts battery power to the ignition system.

One terminal (usually marked "B") will connect to the battery, likely at the starter switch or solenoid, if a starter solenoid is being used, the "S" terminal will connect to the "activate" terminal on the solenoid, one terminal (typically "I") will connect to the ignition system, then there's another terminal to power any accessory loads (IF this applies to your situation).
 
ASSUMING the engine has a "self-powered" ignition system the first rule is to use the proper ignition switch that grounds out the ignition system to "kill" the engine, and NEVER puts battery power to the ignition system.

One terminal (usually marked "B") will connect to the battery, likely at the starter switch or solenoid, if a starter solenoid is being used, the "S" terminal will connect to the "activate" terminal on the solenoid, one terminal (typically "I") will connect to the ignition system, then there's another terminal to power any accessory loads (IF this applies to your situation).
 

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Hello Johnny welcome to YT! YT does not CHARGE by the word! What are you doing with the engine? Are you putting in something that originally did not have this engine in it originally? What is the machine/unit it is going in? It apparently requires some type of lighting so would almost seem that it is a selp-propelled something?
 
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This is what I have and to run light I have a solenoid and not sure wiring all together.
IF your engine has a self-powered ignition system AND you connect to the the IGN terminal on that switch you will destroy it.

You need a different switch, one that is intended for small engines OR an understanding of how to use a relay to transpose the function of the switch's ignition output.
 
IF your engine has a self-powered ignition system AND you connect to the the IGN terminal on that switch you will destroy it.

You need a different switch, one that is intended for small engines OR an understanding of how to use a relay to transpose the function of the switch's ignition output.
OK if that switch not good it had a push button with it ?
 

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Honestly you need to replace a key switch with the same type that it originally had. Failure to do so could result in a few electronic parts getting a little warmer than they were designed for.

If you just want to run small head lights. Would a toggle switch wired to the battery with a fuse not work? It would bypass all of the engines wiring and electronics.
 
Sure that would work. What about the push button start that come with the engine in the picture. Would I need to put a solenoid on to keep battery charging. If I stay with the push button and solenoid how would I wire it? Any help is greatly appreciated
 
I used a toggle switch for lights. Now I just need to know if I need a solenoid or resistor to keep battery charged?
 
I'll jump in here and offer my $.02. You may be confusing the circuit that runs your starter, with the circuit that powers your ignition. On most of these small engines, they will run once the starter gets them going, UNTIL you short out the ignition. That means your ignition switch needs to have a ground function when the key is turned off. Or you could wire a momentary switch to ground, that you hold in until the engine dies.

If you have a multimeter, it should show the "I" terminal on your switch grounds out when in the off position. This has nothing to do with the function when you turn the key to start, which activates the solenoid, which activates the starter to spin the engine. Your picture shows a momentary switch used to activate the starter. You can use this switch to do that, as long as your ignition circuit has an on/off switch also. A toggle switch can do that for you.

You also, probably have a charging circuit from the engine, that keeps your battery charged while the engine is running. That circuit may, or may not run through your ignition switch too. But that circuit is the one you need to tap into with a switch to run your lights. Clear as mud? steve
 
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I haven't been able to locate numbers. The guy I got it from said it was a1992 briggs and stratton twin 18hp i/c series
 
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