Small Engines (Lawn Mowers, etc.): 20HP Troy-Bilt persistant charging problem, triple blade, laymans terms

Question
I'd like to know how to determine if my charging system is working properly on my mower. It is a 1999(I think) Troy-Bilt w/ a 20HP OHV I/C V-Twin B&S.....46" triple blade deck w/ cruise ctrl and it's automatic. Also it has the electric PTO. Please forgive me as I have limited knowledge of this mower...I'm just not sure as to what to be looking for. I can charge the battery w/ a charger, and then start the mower and mow for 2-3 hours before I don't have enough juice left in the battery to keep the PTO live, then I have to charge it again. I know how to use a meter, and I checked for resistivity in the black and red w/ the battery disconnected. With the key in the off position...I get nothing, and when I turn it to ON or Lights, I get a small reading...as I should. I also checked the reading coming from the lead(sorry for the laymans terms here)of the little electrical box that the charging wires go into on the side of the engine and get .11V. Isn't that the wire that should go back to the battery for charging? Right now it splits into red/black and white...both of which go into the starter switch. I'm stumped.....please help! Thanks.

Answer
Hi Michael,

Sorry, I am not familiar with the charging system on your mower.  The output from the charging system should be much higher and as much as 18 volts.  If you are not getting a charge at the battery and the wires are intact, I would say that the charging module or rectifier is bad.

Let me know how you makeout.
Michael