1 wire to 3 wire alternator swap?

[Slide]

Installing a new alternator and found that the one I purchase (Arco 60065 marine) is a 3 wire style instead of the old one wire style. I've been told this is a better setup if wired correctly. How do I properly wire the new alt? My current understanding is that the purple lead goes to the ignition hot and the red lead is a voltage sense line for the internal regulator. Can I jump the red lead to the alt battery post?

 

[Bondo]

Ayuh,... Why wouldn't ya send it back, 'n get the one ya need,..??

 

[alldodge]

I have one of those 100 amp one wire sitting on the shelf, never did like it.

My guess is yours came with the three wire being a 1987 and someone changed it. Looking at the back of the ALT you connect

Red/Purple to Right side 12V constant power
Purple to Left side 12V switched power

The Red purple comes from the 50 amp breaker

 

[achris]

Ayuh,... Why wouldn't ya send it back, 'n get the one ya need,..??

One wire alternators are horrid.. Need to be 'revved' to get them to start charging... No Mercruiser was ever supplied from the factory with a one wire alternator (bless them for small mercies)....

OP...
'Dodge pointed you right...

 

[Slide]

Thanks! There does seem to be a lot of confusion on the subject, but from what I can tell, the 3 wire is definitely a better setup, and pretty easy to set up. I am already tied into the switched ignition lead with my electric fuel pump, so I will add a line there for the purple lead. For the sense lead, I'll just jump it to the battery post on the alt.