Anti-backfire wiring question

[tho9504]

Recently i purchased a used troy-bilt Bronco (i think it's a 2008 model?) from someone. All the wirings on the tractor was re-done with the safety features disabled. Instead of ignition key, there is a toggle (kill) switch to turn on/off power and a push button to start the motor once the toggle switch is in the "on" position. Everything works fine and i have been cutting my yard with it. The only problem i notice it that when i go to shut the engine off (turn toggle switch to off position), there is a loud backfire sound before shutting down that my whole neighborhood could hear. i am sure it has to do with the Fuel solenoid that is attached to the carb bowl.

My questions would be, how do i wire it in since the original ignition was removed and all there is the toggle switch and the push button? Do i ground the solenoid to frame and the positive wire to the toggle switch? Do i need a fuse?

i was hoping to wire it directly to my toggle switch, so when i turn it off, the fuel cuts off immediately and there would be no back-fire. but i am not sure if the fuel solenoid could take 12v directly from the battery or is that took much voltage?

Thanks,
AL

 

[tho9504]

i forgot to mention, it's a Kohler Courage 18 Engine.

 

[bertsmobile1]

The solenoid is normally closed so the plunger has most likely been cut off.
To stop the big bang throttle down for around 30 sec before shutting off.
The solenoids are very expensive but if you want to fit one , wire it to the toggle switch.

 

[ILENGINE]

Also Kohler carbs are setup where the fuel solenoid shuts off the fuel to the high speed jet, but doesn't shut off the idle circuit jet. So if you idle the engine down before shutoff it can still allow fuel to be drawn from the carb into the cylinder and out into the muffler where it ignited. Kohler has always recommended shutting off their engine at full throttle. Of if you don't want to do that then move the throttle to full position after shutting off the key.

 

[tho9504]

The solenoid is normally closed so the plunger has most likely been cut off.
To stop the big bang throttle down for around 30 sec before shutting off.
The solenoids are very expensive but if you want to fit one , wire it to the toggle switch.

Thank you for the quick reply. If i do hook up the solenoid to the toggle switch, do i need to add a fuse or anything? The reason i am asking is because i dont know how much volt the solenoid is designed to taken before getting burned. Can it take the 12v from the battery without any fuse in between? ideally the easiest for me would be to just hook it up to the toggle switch and other end to ground.
I have reduced the throttle all the way down for 30 seconds before shutting off but still made the backfire noise, not much as full throttle but there still was a detination.

 

[bertsmobile1]

No need for a fuse, but one won't hurt
The solenoid draws about 0.25A and is 12 Volts/
It is also about $ 40

 

[tho9504]

Would you happen to know what size fuse i need, if i am going to wire that in through the toggle switch? i know there is a 15 amp fuse somewhere near the starter solenoid. but if i am wire the fuel solenoid, then it would be independent, so i wasnt sure if i should get 10 amp or 15 amp or 20 amp fuse between the toggle switch and fuel solenoid.

Thanks for reply.

 

[bertsmobile1]

It draws about 0.25 A
Anything bigger than that would be fine
1A, 5A or even 10A will do the job.
All the fuse is doing is protecting the harness from a dead short

 

[tho9504]

Thank you all so much for your help.

 

[Fish]

The toggle switch is likely to "ground" the ignition modules, and shut down the engine, so there should be no voltage on that circuit. And you don't want to accidently send any voltage to your ignition modules either...