C45 Dynamo Conversion Positive Earth

I would like to replace the alternator with a C45 Dynamo Conversion Positive Earth. Does anyone have any experience with this? The reason I am considering this is that here in Switzerland we have to ride with the lights on all day. I am afraid that the alternator will not be able to produce enough power. I would also like to change the ignition to an electronic one. An experienced classic car mechanic pointed out to me that an electronic ignition with an alternator does not provide the necessary voltage at low revs, which puts more strain on the battery.


Have you considered LED lighting? You can then retain the originality of the dynamo.

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No modern car has a Dynamo, why do you think the alternator would not support headlights during the day?

I think the O/p is confused and means would like to exchange the dynamo for an alternator.

Hi Geri,

Sure, we have the same, but never ever have I been stopped or ticketed for driving a 70+ year old car in the city.

My experiences:

I have kept the MKV electrics as close to original as possible, makes troubleshooting easy, I am happy with the original distributor, fuel pump etc.

Some other expereinces:

My friends / customers have many modifications done, which makes it a bit difficult and sometimes expensive to truobleshoot. One 1951 MKV Saloon has electric power steering, 123 dizzy, modern 5-speed gearbox etc. It has the positive ground Dynamator which is shot, after ca 4-5 years of life. A replacement has been quoted €1500+ euros plus work.

I have had several generators rebuilt in the UK usually for less than £100 GBP each.

In my experience the original spec generator is enough even when driving with all original equipment switched on, I did my 1st MOT / TÜV in December 2014 in Finland, on the way back it was very dark and snowing heavily, I had the heater fan and wipers and all lights on all the time. No problem.

But I can not recomend for my customer to switch back as I have no idea how much the electric power steering, the reversing camera, electronic ignition etc all need power.

A perfectly standard 1964 Jaguar S Type 3.8L automatic another customer of mine has also drains the battery in city traffic if they drive with the headlamps on.

Fitting LED’s may be one solution, until then I just advised to use low gear (it’s an automatic) and not having the lights on when idling at traffic lights etc, it charges just fine in normal driving.

Just my two Euro cents.


In Switzerland, you will have problems if you want to register a classic car with LED lights as a “veteran”. If a classic car has veteran status, it only has to be presented every 6 years. However, it may not be driven more than 18,000 km in these 6 years.


Hi Geri,

Interesting, I doubt anyone would drive more than 18.000kms in six years with a MKV.

If no LED’s are allowed than no headlights in city traffic should be fine, as otherwise you would very easily run out of battey.

I would do as I have done so far: in daylight no headlamps on it the city, and original electrics.YMMV.