not sure what Im missing here, I rebuilt starters and Alternators on cars,trucks,tractors & heavy equipment and nothing but Electrical work for 13 yrs of my Auto tech work force, I remember the stator putting out same voltage depending upon the RPM in AC voltage and the regulator, so they call them, has 2 diodes in them to turn the AC voltage into DC voltage and some of them have an additional diode to work a charge-light, I refer to them more of a diode rectifier
What you are missing is hands on experience in mower engines thus the knowledge specific to mowers .C
I came into mower repair by accident 11 years ago
I have been working on motorcycles since I was 12 and motorcycles are a lot more similar to mower engines than cars are.
However it was still a very steep learing curve.
people who are willing to step up to the plate and offer support are always more than welcome, but only if he advice is good , relevent and unlikley to confuse
In this particular example
You can not follow the wires as you would on a car where the alternator / generator is a bolt on external item.
In this mower the alternator is a perminant magnet type hidden under the flywheel which in itself is under the blower housing so if you do not know where to look you will never be able to find them.
Next this particular mower will probably have a duel circuit alternator with no actual external rectifier, just a diode in one wire, a system that has never been used on a automobile.
Then it will have an AC output wire that goes diretly to the lights and then the ground is used to switch the lights on & off.
A system you will also never see on a car or truck
And finally it is not regulated.
Usually what happens is the diode goes open circuit so there is no charging , however occasionally they go gloced circuit in which case the alternator pumps AC into the battery .
This system has no points or zenners to chop off excess voltage & dump it into the frame as is done on motorcycles and as it is a perminant magnet system, no field coils that can be controlled in order to regulate the voltage output as is the case with 99% of automative alternators .
Voltage readings on the duel circuit & tri circuit stators is not particular relevent as they supply chopped DC pulces using the battery to regulate voltage.
As such they are very hard on batteries .
Finally with B & S vertical shaft single & twin engines the only place ( that I am aware of ) that B & S put a regulator is on the plastic dip stick tube. Kohler , Kawasakai & Loncin all mount them on the blower housing so the cooling fins are in the direect cooling air flow from the fan .