Over charging
 

I have a model 1872 CC super garden tractor with an 18 hp Kohler engine. I've replaced just about everything on this mower over the past 18 years. The PTO switch went bad several years ago and instead of buying a new one I used a "jumper" wire between the two ports in the plug. I went to use it today and noticed the voltage gauge was way over on charge. I shut it off and decided to put a toggle switch in place of the jumper wire. I started it back up and it was still charging. The two white wires that originally went to the PTO switch, which are joined together, got extremely hot and eventually it blew the fuse that's on the dash. I replaced the fuse and started tracing all the wires to see if any were shorted out. None were found. I replaced the ignition switch and still have the problem. I checked the voltage on the two white wit=re and they are putting out 14.5 volts. If I let it idle the wires get warm. When I go full throttle they get hot and blow the fuse. If I engage the PTO for the deck, the voltage drops to normal. I replaced the relay back when I replaced the ignition switch. I don't know of any way to check the rectifier-regulator. Since it is charging (constantly full charging), that should mean the alternator or stator is working.
The regulator is bolted on the back of the engine in the center and has three wires connected to it. I traced the white wire from the PTO switch and it's connected to the regulator. The other white wire that's joined with the other white wire at the PTO switch goes to the ignition switch.
Would the rectifier-regulator be the problem?

I can not follow your wiring modifications. I sent you a 1872 wiring diagram to the e-mail address listed in your profile.

Thanks Roland!
I ran a test on both the alternator with the rectifier unplugged and the voltage with the rectifier plugged in. The alternator is putting out 40 +volts. The voltage with the rectifier plugged in is 14.9 - 15 volts. From what I have been reading in the service manual, it states if the voltage is over 14.7 then the regulator is bad. Do you think this is the case?

What is the voltage at the battery terminals with the engine running at WOT?

Well, in a phone conversation with this gentlemen this morning, seems it turns out to be a ground issue (of some sort). He ran a test and got the Tractor to work correctly with a "jumper wire".

So, hopefully he reports in and tells us where the actual problem was.

:)