View Full Version : 1984 SS Needs New Alternator

05-31-2011, 10:21 PM
Hi guys,

1984 SS with the Ford 351, and the old Motorola alternator and external regulator. Voltage from a fresh battery was 12.4V (in the driveway) and only 12.5 under throttle, so it appears that the 27-year old alternator is ready for a new home, but not in my boat. The markings are vague, saying Motorola "Listed Alternator 7558", and Motorola "Model BRG2009A" on the regulator. This is a three-wire alternator, but I seem to be having trouble finding the correct replacement. Any cross-references that match this old one? Any brands that people prefer? I added an amp and stereo (but nothing elaborate). Do I move to an HO alternator ? Do I go to the trouble to convert to a single-wire configuration? Advice, experience, etc much appreciated.


06-01-2011, 07:30 AM
Jim... I literally just went through this 3 weeks ago. I have the same boat. I replaced it with a larger 1 wire self exciting alternator. There is no conversion needed. I'm not sure how to direct you to the thread I had... just search it in this category.

06-01-2011, 07:31 AM

there you go!