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3g Overdrive Pulley

1793 Views 2 Replies 3 Participants Last post by  Steve83
Anyone know where I can get a overdrive pulley for the 3g alternator? My pulley now is about 2.5 inches(about 63.5mm) I'd like to try one about 2 inches( 50-51mm) to increase the rpm on the alternator because at idle the voltage is around 12.8 and lights and everything else goes dim in cold rain with everything running.
Yes batt's are good...

Key in if you have any thoughts or info on this pulley I seek


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If the alternator EVER worked with that pulley, then the pulley is NOT the problem. Click these & read the captions:

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I'd also inspect ALL the pulleys, and the serpentine belt, and the tensioner. If the belt is glazed or oily, or if the tensioner is close to its loose limit, a smaller pulley will only make it worse. A smaller pulley also makes the belt bend more, which makes it age faster. And because there's less belt surface area in contact with the pulley, the belt needs more tension to apply the same torque to the pulley, which the tensioner ISN'T built to provide. That also makes the belt more-prone to slip, which causes it to wear away faster. Either way: wash the front of the engine thoroughly with SimpleGreen/PurplePower & a LOT of water, and repair any leaks that could get onto the belt (including oil coolers forward of the fan).
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