Ignition switch spark

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jeeptj1
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Ignition switch spark

Post by jeeptj1 » Thu Oct 20, 2016 5:37 am

So i put the new ignition switch on the mule yesterday and got it running. It started up each time and had no issues. This morning because i dont have the switch in the box yet, i noticed that when i tried to start it there was a spark inside the ignition switch itself when i turned it on. Is it possible that it still starts and runs but the switch is wired wrong or is that what switches do and you just dont see the back of it. Thanks john jr. P.s. Chuck how difficult is it to remove the engine shrouds to check for debris in them. Thanks


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Re: Ignition switch spark

Post by Auto Shop teacher » Thu Oct 20, 2016 5:56 am

I'm looking forward to others reply, but one thing I did just to verify that the mag was working correctly was to unplug the grounding wire at the mag and see if my mule started and ran. If everything worked fine unplugged, and when the engine died when I plugged the mag back in even though my ignition key was in the run position, I knew I had either a bad ignition switch, or had wired it wrong.

Another thing I learned the hard way was I didn't have a good ground (connection to the frame) on my grounding wire on my ignition switch lead on my electric start mule and somehow I cooked the points in the mag. I assume that I had left the key in the run position with the engine off a few times and had 12volts backfeeding the points.

Chuck W.
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Re: Ignition switch spark

Post by Chuck W. » Thu Oct 20, 2016 8:30 am

I am still not clear on which electrical system you have, but you should NEVER see any type of spark at a switch. You are going to have to trace the wires down and see what's going on. It also sounds like there are no fuses in your circuit, a fuse should have blown when you had the spark.

The top shroud is easy to take off, simply turn the 1/4-turn DZus-type fasteners on each side of the shroud (some people install sheet metal screws when the Dzus fasteners fail), remove the choke cable, and you may have to remove the throttle cable (I usually slide the shroud out and don't disturb the throttle cable).
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The one-piece top shroud will lift off:
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The area on top of the left cylinder seems to be the worst for rat nests, but be sure to check both sides. All debris must be removed so there is clear air flow around both cylinders.
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I am really concerned about your electrical system, can you send me some photos of your switchbox, battery box, starter, etc. and maybe I can help more.

jeeptj1
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Re: Ignition switch spark

Post by jeeptj1 » Thu Oct 20, 2016 10:12 am

Chuck got a new battery today and fired it up and didnt see the spark. i think its what you guys have been calling a one wire alternator. The alternator wire goes to the solenoid which is on the starter not separate. The alternator does i believe have a ground wire on it but cant really tell. I will get some pics as soon as i can. I made a new harness up for it today but until im sure of everthing, i will wait for later to install. Thanks john jr

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Re: Ignition switch spark

Post by Chuck W. » Thu Oct 20, 2016 10:20 am

sounds like you may have this style electrical system:

Image

jeeptj1
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Re: Ignition switch spark

Post by jeeptj1 » Thu Oct 20, 2016 11:56 am

Chuck thats exactly how i wired it up. The S went to the bottom of the solenoid, the M went to the magneto, the L was used to energize the electric fuel pump, the G is grounded to the frame, and the B is on the right side of the solenoid. Now thats the way is was wired, i didnt change anything except the new switch., By the way is there a learners manual for these things with four wheel steering cause when my princess wakes up from her nap, She isnt gonna be happy what i did to the yard. Lol. Thanks john Jr. What size in line fuses to use please?

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Re: Ignition switch spark

Post by Chuck W. » Thu Oct 20, 2016 2:59 pm

I use 20 or 25 amp. Locate the fuses as close to the source as possible, right where you are taking the 12 volts off the starter battery terminal. This way, if you have a short, you will blow the fuse instead of burning up the wiring.

Good luck on hiding the damage to the yard!

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jeeptj1
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Re: Ignition switch spark

Post by jeeptj1 » Thu Oct 20, 2016 4:05 pm

Thanks, john jr


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