Alternator not charging

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mini_surfari
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Alternator not charging

Post by mini_surfari »

Morning all,

Trying to sort a problem with a friends car, it’s a 63 with an alternator conversion.

It’s got a dummy control box, brand new Dynamo loom, alternator and battery.

I have IGN light is on when the ignition is on, and dims when the engines running (doesn’t change under load).

The alternator is working, double checked and triple checked all wiring and earths.

What am I missing?
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Exminiman
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Re: Alternator not charging

Post by Exminiman »

Earth strap on engine ?
MagicWandWoody
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Re: Alternator not charging

Post by MagicWandWoody »

'63 would originally be +ve-earth though it likely will have been changed of course. Apart from specialist ones, alternators are mostly -ve earth. Hopefully the car and alternator polarities are matching. But if not, the diodes in the alternator will be destroyed (by massive forward over-current) as soon as the ground and battery terminals are connected.
mini_surfari
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Re: Alternator not charging

Post by mini_surfari »

Thanks for the suggestions guys, turns out the PAL fuse in the control box had burnt out at the bottom!

Now I’ve just got to fix this awful brake judder :lol: when will it end!
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