Need Some Help, Please.

JonnyBlaze

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I just picked up a Toro Timecutter 1742Z. Model 74350. Has the Kohler Courage SV540 18hp.

Has very faint spark if any. I noticed someone has messed with the wiring and there is a black wire coming off the main engine plug just hanging freely. No idea where it goes.

I swapped out a different coil and spark plug. No difference. I also swapped out the module bolted on the back of the motor. No difference.

Any suggestions would be great.
 

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tom3

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Looks like someone has replaced some wiring or that connector at some point, see the crimp connectors. Does that black wire connect to anything on the other side of the plug in connector? Maybe a four wire connector used in the three wire circuit.
 

JonnyBlaze

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Looks like someone has replaced some wiring or that connector at some point, see the crimp connectors. Does that black wire connect to anything on the other side of the plug in connector? Maybe a four wire connector used in the three wire circuit.
I don't see anything on the other side of the plug.
 

bertsmobile1

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I don't see anything on the other side of the plug.

Yes, quite right.
Looks like some one has done an engine swap at some point in time and the new engine had a different plug to the old so they cut it off & joined the wired.
Best guess is the 4 wire plug wasoff a mower that h=used AC headlights.

Next, the magneto is self powering and has nothing to do with the wiring apart from turning it on or off by grounding the kill wire.
A poor spark will be caused by either a bad ground contact between the coil & the mower, a weak magnet in the flywheel, coil fitted upside down ( might even not work ) , too large a gap or wrong coil.
Also the spark is speed dependent, the faster the flywheel spins the bigger & fatter the spark.
Easiest way for you to verify if the spark is OK is to get a 3 contact spark tester, fit it to the plug and crank engine in a dark place.
If the spark can not jump the widest contact you have problems.
If it does jump the the problem is with you not the mower.
 

JonnyBlaze

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Yes, quite right.
Looks like some one has done an engine swap at some point in time and the new engine had a different plug to the old so they cut it off & joined the wired.
Best guess is the 4 wire plug wasoff a mower that h=used AC headlights.

Next, the magneto is self powering and has nothing to do with the wiring apart from turning it on or off by grounding the kill wire.
A poor spark will be caused by either a bad ground contact between the coil & the mower, a weak magnet in the flywheel, coil fitted upside down ( might even not work ) , too large a gap or wrong coil.
Also the spark is speed dependent, the faster the flywheel spins the bigger & fatter the spark.
Easiest way for you to verify if the spark is OK is to get a 3 contact spark tester, fit it to the plug and crank engine in a dark place.
If the spark can not jump the widest contact you have problems.
If it does jump the the problem is with you not the mower.
I dont think its spinning over as fast as it should. Even with a good battery and even a jump pack. Here is a short video.

https://youtu.be/jtWll71rs9g
 
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I just picked up a Toro Timecutter 1742Z. Model 74350. Has the Kohler Courage SV540 18hp.

Has very faint spark if any. I noticed someone has messed with the wiring and there is a black wire coming off the main engine plug just hanging freely. No idea where it goes.

I swapped out a different coil and spark plug. No difference. I also swapped out the module bolted on the back of the motor. No difference.

Any suggestions would be great.



Have you checked the plug with a tester? Some times the spark can seem weak but actually be fine. The video you sent seems normal but thats just me.
 

JonnyBlaze

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Think this originally had a Briggs 17hp and now has a Kohler Courage 18hp. I can't even get the air filter cover off without pulling off the entire right console panel. So, I have a 17.5hp Briggs and I'm thinking I'll pull this Kohler and put the Briggs back in it....
 
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