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How much voltage from an alternator?

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Old Jul 7, 2011 | 05:54 PM
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Default How much voltage from an alternator?

How much voltage should my '69 427 be putting out? It's a 61 amp unit.

My gauge is reading straight up, no discharge indication. My car wouldn't restart the other day, had to jump it. I recharged the battery and started the engine. I put a multimeter to the alternator and it read 11 volts.

If it's time for a chrome alternator...any suggestions?

Thanks
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Old Jul 7, 2011 | 05:58 PM
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Generally it should be putting out 13 volts or slightly more. If it is only 11 there is trouble.
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Old Jul 7, 2011 | 06:24 PM
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Voltage should be 13.8 to 14.2 volts. Good luck.
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Old Jul 7, 2011 | 07:28 PM
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Running the voltage can be anywhere from 14.7v (low battery) to 14v(charged battery) or 55 amps to approx 10 amps.

11 volts is shows not charging and a low battery.
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Old Jul 7, 2011 | 07:43 PM
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You could rebuild yours pretty inexpensively. A lot of articles out there.

You want mine? You pay shipping, that's all. I just ordered a CS144 and won't be needing mine anymore, though I will be needing the pulley/cooling fan off the front for the swapout.
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Old Jul 7, 2011 | 09:12 PM
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Originally Posted by Trip 69
How much voltage should my '69 427 be putting out? It's a 61 amp unit.

My gauge is reading straight up, no discharge indication. My car wouldn't restart the other day, had to jump it. I recharged the battery and started the engine. I put a multimeter to the alternator and it read 11 volts.

If it's time for a chrome alternator...any suggestions?

Thanks
It's never time for a chrome alternator. Seriously.
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Old Jul 7, 2011 | 09:36 PM
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Originally Posted by 69427
It's never time for a chrome alternator. Seriously.
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Old Jul 7, 2011 | 09:56 PM
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Originally Posted by 69427
It's never time for a chrome alternator. Seriously.


Chrome alternators, along with most chrome under the hood, (valve covers, etc.) is just kinda tacky.........I am an advocate of keeping the engine compartment neat and orderly, but purely functional.
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Old Jul 7, 2011 | 10:50 PM
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Chrome dont get you home.
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Old Jul 7, 2011 | 11:46 PM
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I agree with most of the above, including the comments on chrome. Should be 13 volts plus at the battery terminals when running. Not that hard turning a 61 amp unit into a 90. Also, think 69's have external voltage regulators, and probably a good place to start.
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Old Jul 8, 2011 | 09:03 AM
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Thanks all...I guess I had a weak moment in frustration. No chrome, just the factory valve covers.
Shrek, I'll rebuild mine. I had it apart to bead blast the halves and painted them with an aluminum paint. Maybe I messed something up putting it back together but don't think so.
Would anyone be able to steer me to articles on rebuilding?
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Old Jul 8, 2011 | 09:57 AM
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Originally Posted by Trip 69
Thanks all...I guess I had a weak moment in frustration. No chrome, just the factory valve covers.
Shrek, I'll rebuild mine. I had it apart to bead blast the halves and painted them with an aluminum paint. Maybe I messed something up putting it back together but don't think so.
Would anyone be able to steer me to articles on rebuilding?
Here's a rebuilding procedure for the 10si alternator which I believe is what your is. It could be that your voltage regulator is bad, I had to replace mine. It's a pretty easy task and you can get the regulators from most any parts store.

http://www.midwesternmedicalmachine....ild/index.html

Last edited by TopGunn; Jul 8, 2011 at 10:00 AM.
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