How do I replace kill wires.

LarryJohnson

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My B&S v-twin will only fire when the "kill wires" are unplugged from the coils. I understand that this means I've got bad kill wires. What part needs to be replaced. Just back to where the wires are enclosed in plastic, as shown below, or does it go further back. Thanks.
Is it the diode that needs replacing?

Edit: or does that mean one of the safety switches is bad. I checked each one with an ohmmeter and all appeared in working order. It's the first time I've ever done this, but I believe I did it correctly.

Untitled
 
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bertsmobile1

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My B&S v-twin will only fire when the "kill wires" are unplugged from the coils. I understand that this means I've got bad kill wires. What part needs to be replaced. Just back to where the wires are enclosed in plastic, as shown below, or does it go further back. Thanks.

Edit: or does that mean one of the safety switches is bad. I checked each one with an ohmmeter and all appeared in working order. It's the first time I've ever done this, but I believe I did it correctly.

Untitled

:welcome:

the kill wire is a ground circuit so it will either be open circuit ( running) or closed circuit ( stopped ) to ground.
This makes them a touch hard to test .
Not telling us the make & model number of your engine makes it a bit hard for us to tell you how to test the mower.
However if you set the engine is start mode, ignition on , brake on , drive in neutral , PTO off ( remove the plug safety )
Now follow that wire back, testing at every plug.
When you get to one that is open circuit, the previous switch, or the wire between it and the switch you are at is the naughty party.
Check the wire carefully between the coil and the plug, usually hiding behind the starter for any break or wear in the insulation that could be allowing it to short out to the engine.
 

LarryJohnson

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Yes they were smashed behind the starter or by nut/washer. Taping them up didn't solve the issue. Might have to replace front harness. Not sure.
This thread is merging with another of my threads. Let's terminate this one.
 

cpurvis

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If you can unplug the kill wires and the engine runs, then the kill wire from wherever you unplugged it, going back to the engine, is good. The problem lies in the wire going away from the engine.
 

Tinkerer200

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If you can unplug the kill wires and the engine runs, then the kill wire from wherever you unplugged it, going back to the engine, is good. The problem lies in the wire going away from the engine.

You do understand what the Kill Wire Harness of B&S V twin Engines is?

Walt Conner
 

cpurvis

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Maybe not. Enlighten me.

Kill wires I'm familiar with are connected to ground to kill the engine. Do the Briggs wires work some other way?
 

Tinkerer200

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Kill Wire Harness for B&S V Twins connects BOTH coils and has diodes in it to prevent the two coils from interfering with each other, shorting each other out while running, but yet allows both coils to be shorted from a single switch to kill the engine. Not a simple wire and you do not get any closer to the engine ignition than the Kill Wire Harness.

Walt Conner
 

cpurvis

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Kill Wire Harness for B&S V Twins connects BOTH coils and has diodes in it to prevent the two coils from interfering with each other, shorting each other out while running, but yet allows both coils to be shorted from a single switch to kill the engine. Not a simple wire and you do not get any closer to the engine ignition than the Kill Wire Harness.

Walt Conner
Yes, I'm with you. And how does that change what I said about diagnosing the problem?
 

Tinkerer200

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"Kill wires I'm familiar with are connected to ground to kill the engine. Do the Briggs wires work some other way?"

"If you can unplug the kill wires and the engine runs, then the kill wire from wherever you unplugged it, going back to the engine, is good. The problem lies in the wire going away from the engine."

What other wires are there to run back to the engine once you unplug the kill wire from the coils?

Does not appear that you understand the Kill Wire Harness but you are free to say whatever you want.

Walt Conner
 

cpurvis

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What other wires are there to run back to the engine once you unplug the kill wire from the coils?
None! When you break the kill wire circuit in two by unplugging it, you are left with the portion that came out of the engine to your unplug point and the rest of the kill wire circuit which is no longer connected to the coil(s). If the engine runs, there is no problem with this wire from the point where you unplugged it back to the coil(s).

The problem lies in the other portion that, once you unplugged it, is no longer connected to the coil(s).
 
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