"Herb Eneva" wrote in message
...
I just had to replace the battery on my #1 lawn tractor. Since it
doesn`t have a generator or alternator I`m wondering what keeps the
battery charged? I
have found that you get what you pay for. Wal-mart has a battery for
$24.95 and it will last about 2 yrs. Tractor supply has one for $38.95
and it will last about 4 yrs. I went with the good one.


Many of the small lawn tractors have magnets on the flywheel. Often there
is also a magnet on the outside that passes the coils that go to the spark
plugs to fire them. Then around the flywheel ( often inside the fly wheel)
attached to the frame is a coil of wire. Also a diode to convert the AC to
DC to charge the battery. There is no voltage regulator as the ammount of
current put out is not very large. If you ever do run the battery down to
where it will not start the engine, you will probably have to put the
battery on a charger to build it back up . It seldom gets enough of a
charge off the built in generator to do more than just build it back up from
a normal start. If the mower is hard to start and you start it several times
you may have to put the battery on a charger.

The battery is not used except for starting and sometimes the headlights.
There may be a seperate set of windings on the coil of wire to run the
headlights. Many thing depend on the exect mower you have.

This is differant from a car where the alternator puts out way more than
enough current to just build a slightly discharged battery back up. Do not
use a large capacity charger ( like one of the 10 to 20 amp ones) as it may
boil too much water out of the small battery.

Guess that I am living on borrowed time. I have a 'home owners version' of
a John Deere I bought new 6 years ago and it still starts the mower. Do you
live where it gets very cold and the mower gets very cold for long periods
of time ?