Alternator wiring question

[rockeater]

Gents,
I purchased a 130 amp alternator for my 350 mercruiser with dual batteries.



My question is two fold. One, where do all the wires attach to (diagram) and do I need to purchase an external voltage regulator. Some say yes, others no (I have searched far and wide). I think this is a mando alternator rebuild, but not sure.

Rock

 

[achris]

Re: Alternator wiring question

Check the paperwork that came with the alternator, but one of those small wires will be 'sense' and the other ' excitation'. The output is the large stud. The most likely is the red wire is constant 12v and the purple is switched 12v. Just make sure the output wire in your engine harness is up to carrying 130amps....

Definitely internal regulator.

Chris.....

 

[Bt Doctur]

Re: Alternator wiring question

Why in H3ll do people think they need 130A Alternators. Its a boat ,not a fire engine!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
With 671`s we didnt need alt`s that big and these were diesel batteries .
So at 130 Amps you will need at least a 1/O cable.,. (welding cable size)Thats the size of your pinkie going from the alt to the starter post and atleast that large of battery cables both positive and negative