Generator to Alternator Conversion Wiring

We have been providing customers with alternator conversions for generator systems for years. This is a great upgrade for old farm equipment as well as classic vehicles. Attached here is a very basic wiring guide for converting a generator / regulator system over to a single wire internally regulated alternator. The original regulator can remain and the BAT post used for a junction block as the battery connection to the alternator. This line can also be spliced with the regulator removed, or a new line ran from the ammeter to the alternator. The field wire is no longer used and may be taped off or removed.

Generator Wiring:

Alternator Wiring:

As you can see, the BAT post of the regulator is being used as a junction point for the battery connection to the new single wire alternator. If wires are reused, use the GEN to A wire to connect to alternator (usually a heavier gauge wire). The field wire has been removed / taped off and is no longer used.

For an easier alternator installation also check out our universal bracket kit, part number A200:

Be sure to check voltage and ground polarity before purchasing an alternator and always disconnect the battery before making any modifications. Belt sizes may also vary upon application, so pulley may need to be changed.

*If ground polarity is changed at the same time as the alternator conversion (i.e. converting a 6V positive ground system to a 12V negative ground system) the wires on the ammeter will have to be reversed, as well as other system modifications such as coil wires.*

*This is a basic wiring guide and will not cover every application or scenario. Always use caution when modifying a system. While Smith Co Electric deems this information accurate, we are not liable for problems arising from use of this information.

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