Jump to content

Converting to alternator.


Recommended Posts

Ammeter wiring stays the same. Check that the wiring and the ammeter is up to the power rating of the new alternator.

You don't want to set your car on fire by fitting a 75 or 100amp alternator in place of a 25amp dynamo.  That said my PI has a 35amp alternator going through the ammeter.

There's various wiring diagrams around. the bottom line is you need;

a heavy cable from the alternator (35amp lucar, or 2 x 35amp lucar or heavy ring terminal, it depends on the unit) to the battery (via the ammeter if you wish).

a thin wire from the alternator 15amp lucar to the ignition warning light (usually by connecting two wires together at the control box)

You need to look at a wiring diagram of your car to tidy up the surplus wires at the control box.

Link to comment
Share on other sites

If using a original lucas 15/16/17 ACR unit you can use the original 2 dynamo wires to go straight into the back of the alternator with no mods ...control box end-join the 2 thick wires ,join the 2 thin wires and tie back the black one out of the way (earth)...that way you can always return to the dynamo system if required.

Link to comment
Share on other sites


For an even neater job, remove the innards from the control box, and solder heavy wires across the relevant connections on the back or inside.

Then it looks totally standard and you don't have any wires flapping about.

leave the black earth wire unconnected inside.

join next pair, and finally join the last 3 together.

Don't forget to find a suitable Alternator mount for the side of the block, a lot less messy than bodging it onto a dynamo one.



Link to comment
Share on other sites


This topic is now archived and is closed to further replies.

  • Create New...