Alternator wiring, chevy 350/mercruiser

[curtis73]

I got the obvious ones :) I had to completely rebuild my wiring harness when I repowered and now I don't know which wire is which. The back of the alternator has two wires; black and red. To what do I hook those? I assume one is hot and one is ignition if its anything like a car, but how do I hook them up?

[502 JET]

What year and model merc? What make/model altenator?

[curtis73]

Oh boy... its a hodgepodge to say the least. The engine is a vortec 5.7, but the TA is early alpha with a Gen1/MR drive on it. The alternator is a generic marine replacement three wire that I got from Ebasic Power, all hooked up to a home-built wiring harness and on brackets I welded myself. I do it all the time on cars, but they have obvious A and B terminals with a connector and a pink and red wire. This is a black and red wire with no connector so I'm stumped as to which is which. Here's a link to the alternator:
http://www.ebasicpower.com/pc/ARC20104_/MER10I/Alternator%2C+Mercruiser+Inboard%2C+12+Volt%2C+70+ Amp
It looks like this and appears to be an ARCO brand:
http://bpi.ebasicpower.com/mm5/graphics/00000001/ARC20104.jpg

[502 JET]

Here is the info you need. (http://www.ebasicpower.com/charge/alternatorwiring.htm) Its down on the right. Good luck with your project.

[DelawareDave]

I have the same one on mine. Large terminal: hook small red wire directly to it. I put a crimp end on the wire and looped it over. Run 10 gauge wire from there to battery + or same terminal as battery cable on starter. Small black wire goes to IGN side of ignition switch, or another place that is also coming from IGN.

[curtis73]

Awesome, thanks folks.