1 Wire Alternator?

If the charging system is working properly the ammeter should show a slight (2 - 4 amps) charge with the motor running at speed and a fully charged battery. However with a fully charged battery, the the ammeter should indicate a charge of 30 amps or more immediately after starting, then taper off to 2 - 4 amps after running a minute or two.

thanks

1 - Battery drain: Make sure the lights and ign switch are off. Set the multimeter to read DC amps. Now remove the battery ground cable and connect the black meter lead to the battery post and the red lead to a good ground (can use the grounded cable terminal). Begin with the highest amp switch setting on the multimeter, then work down a step at a time until you get an indication. If the meter shows about 10 milliamps or less, that's fine. A higher reading means there's a current drain somewhere, most likely in the alternator. If it goes to 0 when you disconnect the wire from the alternator BAT terminal, the alternator is the drain.

IMPORTANT!! DO NOT turn on any electrical loads (lights, ignition) or hit the starter while performing this test or you will destroy your meter!

2 - Running voltage reading: Set your meter to DC volts and measure the voltage directly across the battery terminals with the motor running at 1/2 speed. 13.8 - 14.5 volts is normal. Less voltage means the alternator is not charging fully, and more means the battery is being overcharged.