Failed Dynamo?

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Andyhereford
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Failed Dynamo?

Post by Andyhereford »

I think I know the answer but just wanting confirmation from you experts.
Have just replaced a brittle wire from the Dynamo to the control box.
Thought that I would check the Dynamo voltage…wires linking the Dynamo terminals method. Under 1 volt being produced.
Replaced wires to Dynamo and revved engine…no movement inside control box.
Checked voltage at Battery…no change in voltage as the engine is revved.
Seems to me that the Dynamo is not producing a satisfactory charge.
I will remove the Dynamo to take a look at the state of the brushes and will replace them if they are worn but it seems to me that, looking at the Manual and Haynes the coils in the Dynamo have stopped working as they should.
A new Dynamo would appear to me to be the cheapest / easiest option. Even if I have to replace the control box at a later date it still seems cheaper than an Alternator and a simpler option for someone of my ability.
Any views advice please. I know the pros and cons of Alternators vs Dynamos but I am just trying to keep things as simple as possible so I can hopefully get the car out on the roads this Spring.
Thanks Andy
myoldjalopy
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Re: Failed Dynamo?

Post by myoldjalopy »

Quick answer - simplest option, replace the dynamo. Assuming it is a fairly standard car and electrics OK until the dynamo failed, then that's the least hassle option - like for like. Remember to polarise the new one before fitting to your car....
MCYorks
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Re: Failed Dynamo?

Post by MCYorks »

You could try repolarising ('flashing') the field coils to re-magnetise them, if you haven't done so already. They can sometimes loose their residual magnetism and as a result the dynamo won't start generating.
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