JD 316 Battery light

[Dyock]

I have a JD 316, 18HP Onan. Battery is a few years old but still starts the tractor, it seems a little weak. The battery light is coming on while the tractor is running and then goes off for a while before coming back on. Should I replace the battery or where should I start?

 

[Bob]

The "battery" light typically indicates whether or not the charging system is working, NOT the age/condition of the battery.

Your intermittent light sounds like a poor connection in the voltage regulator/charging system/ignition switch area. There could be some other poor electrical connection, including grounds between the battery, chassis, and engine, as well as a possibly a bad rectifier/regulator or alternator stator.

For starters, you need to get a voltmeter across the battery terminals and see what the charging voltage is while the light "ON" and when it goes "OFF".