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Generator light comes on at high revs only

Electrical issues
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JohnnyBadBrains
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Generator light comes on at high revs only

#1

Post by JohnnyBadBrains » Fri Jan 02, 2009 1:49 am

On my '56 panhead, I'm running a 12v generator with a Bosch voltage regulator. Lately, the gen light on dash comes on at high revs under a load when in 3rd or 4th gears. Let off the throttle, reducing load, light goes out. Gen light glows lightly at idle as it always has. I've checked/cleaned contacts, reflashed the poles and it is still occuring. Can't find this ssue addressed in any of my books or after searching the knowledge base. Anyone else ever have this issue and identified the cause?



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Re: Generator light comes on at high revs only

#2

Post by john HD » Fri Jan 02, 2009 2:14 am

make sure you double check the ground on your regulator.

including the little jumper wire if it is rubber mounted like a delco.

i recently fixed a buddys bike that had a similar problem by installing a new 6v 2 unit regulator from dixie.

it seems to be working fine so far... will know more when he gets more miles on it next spring.

john

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Re: Generator light comes on at high revs only

#3

Post by mbskeam » Sat Jan 03, 2009 5:17 am

I think it maybe a flying short....
as the armature spins faster,the wires short out. this is what the guy at CE told me years ago when I had to return a regulator under warranty.

mbskeam

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Re: Generator light comes on at high revs only

#4

Post by steve_wood » Sat Jan 03, 2009 1:14 pm

Gotta agree with Mike.

Been through something very similar with mine. Turns out that it's not that hard to remove the generator and take out the armature. Take the armature to a starter motor specialist and have him put it on a growler. However, if it is a flying short, even the growler might not pick it up. Only way to tell would be to replace the armature.

Have you checked the voltage regulator?

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Re: Generator light comes on at high revs only

#5

Post by FlatHeadSix » Sat Jan 03, 2009 1:56 pm

or it could be something simple and easy to fix; have you checked the brushes?

mike

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Re: Generator light comes on at high revs only

#6

Post by steve_wood » Sat Jan 03, 2009 2:26 pm

Good point Mike!

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Re: Generator light comes on at high revs only

#7

Post by RussW » Sat Jan 03, 2009 2:43 pm

I had this happen once. Checked the gen for a "flying short" etc, turn out to be a bolt I used to mount the regulator to the rubber mount bracket was too long. It touched the bracket under the regulator and transfered enough vibration at high RPM to make the reg. points break open/closed. Changed to a shorter bolt, all set. Stupid little thing, huh?

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Re: Generator light comes on at high revs only

#8

Post by mbskeam » Sat Jan 03, 2009 7:56 pm

or it could be something simple and easy to fix; have you checked the brushes?
hhmmm..... :roll: :D

but thats too easy...LOL


mbskeam

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