Briggs and Stratton 407777-0170-G5

Earache

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Hello, Replaced both coils on a John Deere D140 with a twin Briggs 407777-0170-G5. It cured the dead cylinder, but now has a shut down problem. When you turn the key to off it takes a few seconds to stop running. I believe the fuel solenoid is turning off the engine, not the spark being shorted. I replaced the coils with Stens 440-445. The kill wire has 2 diodes in-line. I have ohms one way and not the other. Voltage to the coils?

Thank you
Eric
 

tom3

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A single diode tests as you describe, not sure on the doubles. And I wonder about diodes in a kill circuit. Something odd going on here.
 

bertsmobile1

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Easy check is to fit a red in line spark tester and watch it as the engine comes to a stop.
If it is flashing after you turn the engine off then your suspicions are confirmed .
Do both cylinders and get back
The kill wire is a ground wire and he diode is to prevent one coil sending a false signal to the other one.
 

tom3

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The kill wire is a ground wire and he diode is to prevent one coil sending a false signal to the other one.

Aha! As I've said before, learn something every day on here.
 

StarTech

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Briggs V twin kill circuit.JPG
Note some JD mowers dont the kill circuit connected and depends on the fuel solenoid for shut down.
 

tom3

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The L series diagrams show the diodes in the coil circuits and separate line to the solenoids as above.
 

Earache

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Easy check is to fit a red in line spark tester and watch it as the engine comes to a stop.
If it is flashing after you turn the engine off then your suspicions are confirmed .
Do both cylinders and get back
The kill wire is a ground wire and he diode is to prevent one coil sending a false signal to the other one.
Sorry I did not reply earlier. Found the notification in my spam folder. :(
With spark tester, both cylinders spark until rotation stops. Also with the key on, I have battery voltage on the kill wire.
 

Earache

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View attachment 54103
Note some JD mowers dont the kill circuit connected and depends on the fuel solenoid for shut down.
This wire diagram is correct for my mower D140. The question I have is, Why power going to the coils? 13 plus while engine running. Did the original coils need power?
 

Tinkerer200

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B&S engine coils do not need nor want battery power to them. That is a death Nell for B&S coils.
Walt Conner
 
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