Help ....Stupid riding mower

^^ This and most of these have a simple single diode. That is, the stuff under the flywheel outputs AC. Usually there's a single diode in series to rectify to DC The diode could be bad.

If you look around, you can usually find someplace.....maybe even the PITA Sears to download the destruction manual.

Also the Briggs site (if that's what it is) has manuals for their engines