Greg & Keith:
1. According to my tests, the 1401 alternator puts out 30+ AC volts at the output plug; thus no rectifier.
2. The Kohler must have a built in rectifier, because I have AC going in and DC coming out.
3. The part # ST435081 is jacksmallengines.com part number, but might be the same as Kohlers.
4. Keith: The Kohler regulator looks different (smaller), and I cut the plug off the old regulator and used connectors to hook the old plug to the new regulator. That way I can always go back to a Yanmar reg. and plug it in.
It comes with instructions as to AC in, ground, DC+ out, etc.
When I get home I can take a look at the wire colors. Some of the newer Yanmar regulators have a 6 prong plug, and not 4 prong like the 1401. Two of those prongs are not used. If it stops raining, I will post a picture of it and the wiring.
Jim