Charging light on at higher rev around 39mph

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teohenghooi
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Charging light on at higher rev around 39mph

Post by teohenghooi »

Hiya,need help on this.My 1963 morris minor charging light on which indicate no charging.Check and found wiring to dynamo broken.Fixed but now the charging warning light on when I rev to 30mph.Please help.Thanks.
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bmcecosse
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Re: Charging light on at higher rev around 39mph

Post by bmcecosse »

Is the belt tight? And maybe new brushes in the dynamo will help.
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teohenghooi
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Re: Charging light on at higher rev around 39mph

Post by teohenghooi »

thanks.I will try to tighten the belt and change the brushes.
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oliver90owner
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Re: Charging light on at higher rev around 39mph

Post by oliver90owner »

thanks.I will try to tighten the belt and change the brushes.

No. Check before tightening or changing.

Overtightening the belt will only cause damage and changing brushes unecessarily is simply non-productive.

That is jusf what useless garage services do. Charge for the wrong repair, then charge for another change, then ...

Proper diagnosis before acting is far better than guessing and hoping.
myoldjalopy
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Re: Charging light on at higher rev around 39mph

Post by myoldjalopy »

Does the light go out at all at higher speeds (i.e. 40/50/60mph)?
simmitc
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Re: Charging light on at higher rev around 39mph

Post by simmitc »

Just to confirm that it is still a dynamo and not converted to an alternator?

When the wiring was broken and repaired, what exactly was done?

If I understand correctly, you switch the ignition on and the warning light comes on. Start the car and the warning light goes out, but then as you speed up, the light comes back on?

Is it definitely the charging light - no possibility that it has got swapped with the oil pressure warning light?

Does running a load such as the headlights make any difference to the symptoms? Do the headlights illuminate normally (not dim) and do they get slightly brighter when revving the engine?

Do you have access to a volt meter or multi-meter for further diagnostics?

Sorry, all questions, just trying to home in on the cause of your problem.
bmcecosse
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Re: Charging light on at higher rev around 39mph

Post by bmcecosse »

My answer was in the form of a question about the belt tension - and a suggestion that perhaps new brushes would help. Mainly because they are cheap and easy to do, and at higher revs old worn brushes can start to 'float' on the comm. My answers now seem to be getting pretty much automatic 'negative reactions' from a certain new poster to the forum - for no good reason that I can see. Yet no worthwhile better suggestion is ever made ? So -- i'll try again - is the belt tight? And if so - I suggest that perhaps new brushes may be worth trying.
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SteveClem
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Re: Charging light on at higher rev around 39mph

Post by SteveClem »

No bad thing when two experts disagree. It can be very educational to the run of the mill owner.
bmcecosse
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Re: Charging light on at higher rev around 39mph

Post by bmcecosse »

I don't see any disagreement - just challenges to pretty much whatever I suggest - and few alternative suggestions offered.... However - I've made a place on the naughty step, so I won't be bothered in future. :lol:
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oliver90owner
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Re: Charging light on at higher rev around 39mph

Post by oliver90owner »

My reply was to the OP. Simply making suggestions is OK, but the OP bljndly following , without any regard as to whether the suggestions will make any difference is rediculous. If the belt is already properly adjusted, tightening further is not the answer. The belt might even be beyond its service life and not driving on the V, for all we know.

Always best to keep an open mind on possible causes. Dismissing possibles before checking them out is a bit 'tunnel vision'.

Moderated slightly to comply with Ts&Cs. 11/6/16.
teohenghooi
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Re: Charging light on at higher rev around 39mph

Post by teohenghooi »

Hi everyone, thanks for all the valuable suggestions.Checked the belting...still ok.Checked the broken wiring to the dynamo.Still connected.Dismantled the dynamo and checked the brushes.Brushes okay.Hmmmm.Later bought a cable lug to connect the wire direct to the dynamo instead of a terminal to connect the broken wire.Went for a test drive.Voila.Problem solved.Possible causes might be the broken wiring which I connected.Maybe it does not allow enough amp to pass through it?I doubt.Fine for three days now.Thanks again and cheers to everyone.
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myoldjalopy
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Re: Charging light on at higher rev around 39mph

Post by myoldjalopy »

Well it seems the wiring connection was a bit dodgy........glad it is now sorted and you can enjoy driving again :D
oliver90owner
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Re: Charging light on at higher rev around 39mph

Post by oliver90owner »

Well done for not simply tightening that belt or changing out perfectly good brushes. It most certainly requires an open mind and checking out all possibilities before jumping to conclusions. Once again, well done!

RAB
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Re: Charging light on at higher rev around 39mph

Post by amgrave »

So nice to see a thread come to an end unlike all the ones left open. :D

bmcecosse
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Re: Charging light on at higher rev around 39mph

Post by bmcecosse »

Well done !
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oliver90owner
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Re: Charging light on at higher rev around 39mph

Post by oliver90owner »

Just goes to demonstrate that there are often unconsidered alterations that are not immediately clear of operational implications. Also that the regular 'guessers' are not always thinking widely enough 'outside the box'. Often new, systematic approaches are more effective than the hopeful 'change this and change that' approach.

Other options, and explanations for those possibilities, often trigger a more useful analysis of the problem without recourse to potentially damaging (or unnecessary) replacements.

RAB
teohenghooi
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Re: Charging light on at higher rev around 39mph

Post by teohenghooi »

bmcecosse wrote:Well done !
Many thanks,my friend
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teohenghooi
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Re: Charging light on at higher rev around 39mph

Post by teohenghooi »

oliver90owner wrote:Just goes to demonstrate that there are often unconsidered alterations that are not immediately clear of operational implications. Also that the regular 'guessers' are not always thinking widely enough 'outside the box'. Often new, systematic approaches are more effective than the hopeful 'change this and change that' approach.

Other options, and explanations for those possibilities, often trigger a more useful analysis of the problem without recourse to potentially damaging (or unnecessary) replacements.

RAB
Dodgy wire connection is the cause.My mistake.Anyway learn from mistake.Cheers again,my friend.Many thanks
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teohenghooi
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Re: Charging light on at higher rev around 39mph

Post by teohenghooi »

amgrave wrote:So nice to see a thread come to an end unlike all the ones left open. :D
Thanks
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teohenghooi
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Re: Charging light on at higher rev around 39mph

Post by teohenghooi »

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