Uses of a dual pulley alternator?

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AuroraGirl

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Did it drive an Accessory? Or maybe no slippage?
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Grit dog

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Dual belts is for slippage on high amp alternators.
 

AuroraGirl

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Is there a way to bench test it, like would an autopart store know what amps it puts out?
 

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**** can it and convert to a serpentine setup.
 

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I want to replace my alternator and it has a sticker that said "GOOD" If I can know it's good, why would I spend money on a serp setup?
 

bucket

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Olds or Buick used a double groove pulley on the alternator at some point. I don't remember which, or it might have been both.
 

AuroraGirl

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Autozone can test it free
But can they load test, like will their rig tell me what kind of amps it puts out? If it is a 60 amp alt that puts out 60 amps thats great, but i need more lol. Ive had them test ignition modules, starters before
 

AuroraGirl

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Olds or Buick used a double groove pulley on the alternator at some point. I don't remember which, or it might have been both.
Do you know why? Maybe they were in diff spot accessory wise? So ran another?

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Out of corner of picture(I can look in person) it looks like its got two belts, one that surpasses it and uses it as an idler essentially for the AC compressor.
 

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Do you know why? Maybe they were in diff spot accessory wise? So ran another?

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Out of corner of picture(I can look in person) it looks like its got two belts, one that surpasses it and uses it as an idler essentially for the AC compressor.

Yeah, because of the A/C I guess. Non A/C probably used a single groove.
 

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Both of the medium dutys I have tinkered with (both 366's) had dual groove alternators, just two belts running the same route on those.
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80BrownK10

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Some of its probably also redundancy, so that you have two belts running a key accessory like a water pump, alternator or ps pump
 

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