This is how I converted my Herald to negative earth.

1. Disconnect the battery

2. Remove the battery from the tray
3. Refit the battery around the “other” way

4. Connect the terminals in the correct
configuration for negative earth

5. Swop the LT connections on the ignition coil
to also reflect negative earth configuration
(you may have starting problems if you don’t)

Please go to this link where there is a basic
but very clever way of testing if the polarity
is correct. here is the test

6. Remove the large terminal from the dynamo

7. Take a piece of wire connected to the live
terminal of the battery and “flash” it on the
dynamo terminal a couple of times(it will spark)
The dynamo should now be repolarised
Refit the large terminal to the dynamo

8. Start the engine and check the charge rate
of the dynamo

In my case the dynamo charged prefectly first time, you may however need to flash it again if the charge rate is not sufficient.

My fuel gauge and wiper motor appear to work OK, I will therefore be leaving them alone!

The heater blower also appears OK, however I will swop the wiring over in the near future to see if there is any difference in the operation pos to neg.

Please don’t take this method as the same in all cases, follow these steps at your own risk 🙂

Coming soon “The Alternator”