Bench testing alternator

Sep 24, 2018
3,285
Catalina 30 MKIII Chicago
I just cleaned and replaced a few parts in an alternator that fried when the PO reversed battery cables. I'm looking to get this bench tested at an auto parts store as the yard is not close to me. For bench testing purposes I know I'll need to connect the positive to the sense. Looking at wiring diagrams it appears that the key switch I terminal gets connected to the exciter terminal. Assuming that this is positive, I'm guessing that to test this alternator the positive should also be connected to the exciter terminal? This is a Prestolite 51A alternator off of an M25-XP
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,799
CAL 35 Cruiser #21 moored EVERETT WA
I took an alternator to an auto electric shop. He put the unit on his test equipment. Spun up the alternator and provides me the specifications of the alternator. Then sold me a replacement that improved my alternator performance.
 
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Feb 26, 2004
22,987
Catalina 34 224 Maple Bay, BC, Canada
I'm looking to get this bench tested at an auto parts store...I'm guessing that to test this alternator the positive should also be connected to the exciter terminal? This is a Prestolite 51A alternator off of an M25-XP
If that's what you're gonna do, let them deal with the details That's what they do.
 
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Likes: jssailem