20A Fuse keeps blowing

reeftank_man

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I bought this 2006 model 13AX60TG766 Super Bronco. It worked fine for a couple weeks then wouldn't crank. Checked and found a 30A fuse in the socket. Replaced it and it immediately blew again. I Looked over the wiring harness and it was pretty butchered and found that if I unplugged the voltage regulator the fuse did not blow. I did find a bunch of wiring that had been spliced and done poorly, melted insulation, all white replacement wires, even bypassing some of the safety features.

I bought a new harness along with a new ignition switch module (Old one was worn out and the hole totally screwed up). Replaced the voltage regulator. Got it all installed and noticed during installation that the 6-pin white plug next to the starter has an extra wire on the engine side as compared to the harness. Not sure if that is an issue or not. As soon as I plugged in the battery the fuse blew again. Unplugged the voltage regulator and replaced fuse and it is fine. I know if I plug in the voltage regulator it will blow again.

Added: Continuing troubleshooting on the wiring. I found 0.3 ohms between the 2 outer white wires and infinite between each white wire and the center pin with the orange and purple wires on the plug that goes to the voltage regulator.

Measuring on the old regulator from top to bottom;
Top to Middle - 0 ohms Reverse leads - 0 ohms
Top to Bottom - 13 Megohms Reverse leads - 11 Megohms
Middle to Bottom - 11 Megohms Reverse Leads - 13 Megohms

Newer regulator readings are similar to those above.

Added #2: Got a new regulator in case I destroyed the other one. Made my resistance readings before putting it on the mower. Pin 1-2 read near 0 ohms both ways. 1-3 and 2-3 both read infinite one direction, 2.9Mohms with leads reversed. Put it in and the fuse promptly blew again when I connected the plug to it. Took the newest regulator off and rechecked the resistance readings with no change, so I think this one is still good.

I took the top cover off the engine and found a loose red wire. A white wire goes to the ignition module(?) and the red one is loose. (Pic added) No idea where this goes. I found it tucked down behind the air cleaner. The engine is a SV590S-0017 model.
 

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ILENGINE

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There are two white wires that connect to the regulator. check continuity from each white wire to the engine block, should be infinity resistance. On Kohler the regulator is a half wave rectifier so in your case the center(battery) and the top pin are connected together which is normal. But if the stator under the flywheel is shorted to ground it will cause a short between the battery and the shorted to ground stator when the connector is plugged into the regulator which I suspect is what is blowing the fuse.
 

reeftank_man

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Very wise very wise......

Looks like an old mud bog kids machine. She is filthy.
I had the top off the engine today. Didnt see any debris or dirt accumulation. Did notice a small bit of oil at the front of the engine.
 

reeftank_man

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There are two white wires that connect to the regulator. check continuity from each white wire to the engine block, should be infinity resistance. On Kohler the regulator is a half wave rectifier so in your case the center(battery) and the top pin are connected together which is normal. But if the stator under the flywheel is shorted to ground it will cause a short between the battery and the shorted to ground stator when the connector is plugged into the regulator which I suspect is what is blowing the fuse.
I just checked. Sure enough, 0.2 ohms from wire plug to engine block. Thanks!
 
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