dynamo

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Brian Cox
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dynamo

Post by Brian Cox »

2 years ago on advice from local garage, I fitted a new dynamo. Previous dynamo was not charging the battery. Have checked connections, fan belt tension etc. but I am still having to put the battery on a charger every now and then, which makes me think there is still something not right. I have seen the notes about flashing the dynamo, I did not do this. Could it be that which I need to do to make the dynamo charge up the battery ? :cry:

Brian Cox
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Re: dynamo

Post by Brian Cox »

Just remembered to say it's positive earth :eyes:

Bensdexta
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Re: dynamo

Post by Bensdexta »

Brian Cox wrote:Just remembered to say it's positive earth :eyes:
First off Check the dynamo voltage output when the engine is doing say 1500rpm. Its should be at least 14.5Volts.
Bensdexta - 1961 working for a living!

russelm
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Re: dynamo

Post by russelm »

The dynamo flashing procedure is there to 'magnetise' the dynamo iron core.

As a result of this, the dynamo when first turning works as a permanent magnet generator and creates some volts (although little power), this voltage is enough to close the field contacts in the regulator and apply a current to the dynamo field winding and the generation starts.

So its easy to tell if the dynamo requires flashing as the regulator will not kick in
Mark Russell - 1959 Standard Dexta - Work In Progress!

Brian Cox
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Re: dynamo

Post by Brian Cox »

Hi Russelm, pardon my ignorance but how can you tell if the regulator has done it's bit :mrgreen:

Brian Cox
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Re: dynamo

Post by Brian Cox »

sorry, I'm gone till Monday night now, be back on then :buddies:

ianpdexta
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Re: dynamo

Post by ianpdexta »

Does the warning light come on before you start then go off once the engine is running? if so the dynamo must be generating something. For a crude check as to whether it is charging or not, just pull the output wire off the dynamo when the engine is running at say 1500rpm, you should see a spark. Another option would be to switch the headlights on, they should be brighten up when you increase the revs from tick over.

Hope that helps

Ian

Brian Cox
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Re: dynamo

Post by Brian Cox »

Went and purchased a tester tonight, will test for charging tomorrow :buddies:

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