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ray_mcavoy · 09-05-2017, 09:56 PM

Yes, the alternator in the O'Reilly link appears to be an internally regulated Delco 10SI.

If it's charging okay but draining the battery when the engine isn't running, check to make sure the 2 wires that plug into the alternator aren't accidentally swapped. If you unplug the connector and measure the voltage on the two wires, the wire that goes to terminal #1 should only have power with the key on while the wire going to terminal #2 should be live all the time. The terminal identification markings (#1 & #2) should be cast into the alternator case.

09-05-2017, 09:56 PM	#2
ray_mcavoy Registered User Join Date: Nov 2009 Location: Sherman, ME Posts: 2,355	Re: Alternator with internal regulator Yes, the alternator in the O'Reilly link appears to be an internally regulated Delco 10SI. If it's charging okay but draining the battery when the engine isn't running, check to make sure the 2 wires that plug into the alternator aren't accidentally swapped. If you unplug the connector and measure the voltage on the two wires, the wire that goes to terminal #1 should only have power with the key on while the wire going to terminal #2 should be live all the time. The terminal identification markings (#1 & #2) should be cast into the alternator case.