Could that perhaps be a CH20-65
432? That's the closest I find in Kohler database.
If so, the regulator is part number 41 403 10-S. Here's a link for sources and price comparison:41 403 10-S
It will be bolted to the side of the engine (look at the pictures on the link to see what it looks like, please) so you just unplug the three-wire connector, unmount the old on, put the new one on, and re-attach the wires.
However, I'm just a bit concerend about whether we are absolutely this is the problem and not the stator. So I'm going to post some troubleshooting steps just to cover the bases in case this hasn't been done yet.
Disconnect the wire from the center connection of the rectifier/regulator and start the engine. Test for voltage between the center terminal and ground. With the engine running at 3600 RPM you should be getting 13.8 volts DC or more. You can also do an amperage test we can discuss, but this is a good basic test.
If you have less than 13.8 VDC, then disconnect the two outside wires from the rectifier/regulator and test the stator. Switch the meter to read AC, and with the engine running at 3600 RPM you should get at least 28 VAC across the two outside wires.
If the stator is OK, and you are not getting DC voltage out of the rectifier, the rectifier-regulator is bad. If the stator voltage is less than 28 VAC, the stator is probably faulty. you can test it further using an ohmmeter.
With engine stopped, measure the resistance across stator leads. You should get a reading between 0.064 - 0.2 ohms. If you read infinity (no continuity), the stator is open and should be replaced.
Next with the engine stopped, measure the resistance from each stator lead to ground. If the resistance is infinity ohms (no continuity), the stator is OK (not shorted to ground). If you read some resistance (or continuity), the stator leads are shorted to ground and the stator should be replaced.
If it does happen to be the stator instead, here's the part number and a link to sources:Kohler 54 755 09
Hope this helps. Keep me posted, please.
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