Dynamo to alternator

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Dynamo to alternator

Post by Daren » Wed Apr 20, 2022 6:58 pm

Hi all , have started up my 10 , but the amp meter was not working ? But when I increased the revs there was a big flash from the dynamo, and now the ignition light won't go out. Unless diss connect the battery.....

So I think for some reason the dynamo has blown up ,,,,!##@!.
So I wondering if any one has changed the dynamo to an alternate, if so how..

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Re: Dynamo to alternator

Post by robertT » Wed Apr 20, 2022 8:55 pm

No, I'm trying to keep mine as original as possible, but i have found a good vintage Dynamo repair man in Preston after the solder (and copper) in mine went liquid

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Re: Dynamo to alternator

Post by peter_winney » Thu Apr 21, 2022 8:33 am

Don't do it! I bought a 10 equipped with a alternator. There is no way to fit a fan on a bog-standard alternator pulley and I had to fit an electric fan to keep the engine from overheating (in previous ownership it never went far enough to get warm). A replica dynamo-style alternator costs an arm and a leg - considerably more than having the dynamo rebuilt.
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Re: Dynamo to alternator

Post by Rod » Thu Apr 21, 2022 9:22 am

Sounds like the cut out points have welded shut. No offence Daren, but there is more to dynamo charging systems than appears at first glance, and its impossible to diagnose reasons for this happening (and there are several possibilities) by remote control (ie via forum posts). My suggestion, fwiw, would be to find a competent auto sparky who is conversant with dynamo systems and let him/her have a look. If the points are stuck shut the battery is trying to motor the dynamo so you should be able to drive the car, if you disconnect the field and output wires at the dynamo and secure/tape them safely away from shorting to earth. Provided the battery is up you will get a considerable distance with a defunct dynamo so long as the headlamps aren't being used. Obviously if the ammeter pegs itself on the discharge side of the scale and/or you smell burning its a tow job.
Peter is correct, there is nothing to be gained fitting an alternator-particularly a Dynator- unless there is absolutely no alternative (such as a 'unicorn' dynamo-which yours certainly isn't). I had a set of C45 field coils that a previous owner (who fancied himself as an auto sparky) had let the smoke out of rewound from scratch at a modest cost.

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