Hello all and thanks for the help. My 1987 Mercruiser 5.7 is not charging the battery. After doing a couple tests I have determined that the alternator is bad. Unfortunately I can not find the right alternator for the thing. The alternator that I took off has 3 wires- black (ground), purple (connected with a butt connector to a red wire off of the alternator) and an orange wire (battery?). The wiring harness to the alternator had an extra wire (with the end covered in electrical tape) that was a faded red color. I'm guessing that the alternator that I just pulled off replaced a different (original?) type but it must have been working for many years without the faded red wire hooked up. Does anyone know what alternator would have come on an 87 5.7 or what I might have now? Should it be internally or externally regulated?
Thanks!
Thanks!
