ALternator Testing and Loosening belt to remove

06-19-2005, 01:53 PM
93 GMC Jimmy 4.6Vortec W
New Battery is just above 12 volts w/ engine running and off. From what I've researched here, I'd guess my alternator is failing and sucking my battery dry. Just replaced the battery, which was hovering at 10volts before it died while at a red light and would not hold the charge once installed.

My Haynes manual says I likely have the newer CS alternator which has to be taken to a dealer or automotive shop to be tested. I thought I'd check in here w/ the Jimmy Guru's - who so graciously helped me succesfully replace my CPI unit recently - before I take the truck in.

Second - Can someone tell me how to loosen my belt so I can remove the alternator (assuming it'll need to be replaced). Here is my configuration diagram w/ letters in case you can simply let me know which one I need to loosen. Over my head? Not with your help!

Oa Ob(alternator)


Thanks for your attention!!!!


06-20-2005, 09:35 PM
Autozone will check it out for you for free and will also install a new one, if needed, at no cost on labor.

06-20-2005, 09:45 PM
I dont know about installing it, but yea, AutoZone checks it for free. to remove the belt, I dont know how yours is set up, but ive seen 2 different ways. If yours has a automatic tensioner, just loosen the tension on it by turning it with a ratchet with no socket or a belt tool counter clockwise. the other way is that the alternator itself is the tensioner, if thats the case you just need to loosen the bolt on the bracket and move the alternator down some to take the tension off, then take the other bolts off and remove the alternator.

06-23-2005, 12:35 PM
My 93 w motor uses a tensioner with a socket. Rotate to loosen and same to get new belt back on.

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