Hustler Z not charging

I have the same problem on a Fastrak Mini Z with the 16hp Honda GXV530 PXA1 GJARM-1056043 with 18amp charging stator. My battery will start the machine for awhile until the battery is drained but works fine after a full charge. I get no DC voltage back to the battery. The stator has very low resistance and at idle at least I get about 15 VDC when hooked to the two stator wires.d

Is there anyway someone could post the test parameters for that engine? The ones for the 24hp don't match what I have.

Also, does anyone know if I can take a rectifier from a Kohler Command 15hp and use that in place of the Honda part?

Thanks in advance;

Randy