charging system

[michael_johnson]

i have a 2006 fonton 254 tractor the altenater is charging 18 volts so is it the altenater or voltage regulator

 

[Roadworthy]

The alternator puts out a higher than necessary voltage. The voltage regulator should drop it to around 13.5 to 14.5 or fifteen volts. However if the wires are not connected to the battery they have no reference point. How high does the battery charge? If charges the battery to eighteen volts you probably have a regulator problem. If it charges the battery to fourteen volts or so, after the engine is turned off the battery will drop down to the normal 12.6 volts.

 

[rScotty]

If it is wired right, and the alternator is putting out DC voltage, and the battery is good, then the problem is most likely in the voltage regulator.

Alternators by themselves are made to put out 14 volts at a fast idle and it is normal for them to put out more voltage at higher RPM. The Voltage Regulator's job is to reduces that to a voltage that charges the battery properly. For a 12 volt battery the charging voltage is around 14 volts.... just as RoadWorthy said.

 

[LD1]

Where are you measuring the 18v at?

 

[Tinhack]

This looks like it's going to be a fun read.

Perhaps your volt meter is incorrect or it's on the wrong source setting.

 

[Doughknob]

i have a 2006 fonton 254 tractor the altenater is charging 18 volts so is it the altenater or voltage regulator

Rolls eyes