can anyone recommend a alternator for bmc vendette engine  1100 that's reasonably easy to fit i have the old dynamo thanks

I don't think it's that simple. I suspect a Lucas A127 clone will bolt on ok but there are electrical alterations to make too, I suspect. With a dynamo you'll have a regulator somewhere, not in the dynamo. This needs removing and the alternator wiring in correctly.

 

 

As long as the dynamo has been polarised for negative earth it should be simple enough, but if the boat is wired positive earth, that will need converting to negative earth. As long as there are no components with electronics in them (like LED bulbs) it should be fairly simple to do.

 

You will need a different bracket to support the back of the alternator or a long  bolt and packing pieces. The dynamo is longer than the alternator. You will probably need a longer adjusting bracket and longer V belt.

 

An A127 should fit.

 

A modern A127 will deliver about three times more current than the dynamo could so you need to run a heavier main charging cable. Ignore the existing dynamo one.

 

Now the hazy memory bit - take the warning lamp cable off the D terminal on the regulator, splice a length of cable to it and connect it to the D+ connection on the alternator. I think that is correct, but it won't hurt anything if it is not. If that does not work, run a cable from the ignition on terminal on the ignition switch to the warning lamp and from that to the D+ on the alternator.

 

Join the cables on A and A1 at the regulator

 

Once you are sure it is all working, cut the redundant cables flush with the loom and wrap in insulation. Remove and discard the regulator

thanks very much everyone much appreciated

19 hours ago, darlo said:

can anyone recommend a alternator for bmc vendette engine  1100 that's reasonably easy to fit i have the old dynamo thanks

 

Point of Order...

 

If you've been googling for information its spelled "Vedette" not "Vendette", which might have been messing up your results. 

 

 

On 18/10/2025 at 17:44, Tony Brooks said:

A modern A127 will deliver about three times more current than the dynamo could so you need to run a heavier main charging cable. Ignore the existing dynamo one.

 

A further point. Some/many marine conversions used the aluminium cased "sealed" dynamo regulator, if this Vedette uses one of those 3 times more current is a massive underestimate, because they were matched to the non-ventilated dynamos and I think they topped out at about 10 amps.

 

Also, ref the back support bracket and adjusting arm, if you can source them from any later BMC A series engine they should fit, so Metro, later BMC minis, 1100s, 1300s, Allegro, Sprite and derivatives. I am not sure if the Maestro came with an A series lump in it.

 

Edited October 20, 2025Oct 20 by Tony Brooks

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Edited October 20, 2025Oct 20 by Eeyore