Small Engines (Lawn Mowers, etc.): battery not charging on craftsman 18.5 HP lawn tractor, craftsman lawn tractor, fuse holder

Question
I have a Craftsman Lawn Tractor, Model No. 917.273643.  The ampmeter will not register postive, and I can only mow as long a charge last.  Then I must remove the battery and put it on charger.  We replaced the regulator but that did not help.  Any idea as to why the battery is not being charged while mowing?

Answer
If the battery will not hold a charge: The problem is either a  bad battery, or a problem in the charging circuit. First, charge the battery. If it is at all low, it will not start the engine. Clean all connections, corrosion is 80% of all electrical problems.  Dis-connect the battery cables and clean both the battery terminals and battery cable ends with a wirebrush.  Check that the fuse is not blown. In the wiring harness somewhere there is usually a fuse, look under the dash or  follow the wires the come out from under the flywheel. There will be a fuse holder & fuse. The battery should read 11-13 volts, check it with a voltmeter and record the reading. Then check the battery voltage with the engine running (if possible) it should be higher, about 13.5 volts if it is, the charging circuit is functioning. The typical battery lasts 4 years.  Most auto parts stores will load-test it for free, but charge it first for an accurate reading.

The following website contains information on Briggs alternators.  Check out the link for more info.

http://www.briggsandstratton.com/miscpdfs/RNT/alternator_replacement.pdf

Do you have a voltmeter to do some basic tests?
Let me know.
Eric