Small Engines (Lawn Mowers, etc.): Kohler 15.5 hp engine, craftsman riding mower, alternator repair

Question
Hi Allen,

I have a seven year old craftsman riding mower with a 15.5 hp kohler engine. The past two cutting seasons I have had a charging problem. I have put a new battery in this year and checked the charging output it is 12.66 volts. I don't think this is enough voltage to charge the battery. Should the engine be putting out 14.0 volts to charge the battery? If so what part of the engine would be bad and where is it located. The rest of the mover is in good working order.

Thanks

Mark  

Answer
Mark you are correct, 12.66vdc is to low.  The generator output should be 13.8VDC.  What you're seeing indicates worn brushes in the generator.  I can't tell from your info if your machine has a seperate starter or a combo-starter/generator.  In either case, the generator must be taken apart and its brushes replaced.  The commutator (part the brushes ride against)  also will need cleaning.  Best bet is to take it to an alternator repair shop & let 'em do it right (hint- ask local shops who does their alternator repairs) ;).  You'll find THAT shop can get it done quickly and for alot less!