Alternator & Cable Upgrades

[SeaNymphFM161]

On my 2000 Bayliner Ciera 2655, I have a 5.0 Mercruiser. I'm planning on upgrading my alternator from the stock 65 amp, to a 105 amp unit (https://www.hardin-marine.com/p-104...high-output-replacement-for-merc-862031t.aspx). With that, I need to upgrade its wiring to handle the amperage. Not looking to start a debate on whether its a ground, or neutral or negative or some other AC vs DC wire. I need to simply know where the black wire from the alternator attaches on the other end. My fat toe doesn't fit under the motor to see. I assumed it terminated to the bolt which holds the coil on, but an ohm test proved me wrong. I'm a picture / PDF / diagram kind of guy. Later, I'll upgrade the charging wire as I route it to a 3-bank battery isolator. Thank you much - Matt.

 

[Scott Danforth]

there is no debate, not sure why you are coming across as confrontational

wireing depends on the alternator you have. Delco, Mando, etc.

however there should be at a minimum, the ground cable, the battery charge cable and an excite cable from the ignition (usually purple). you will need to increase the size of both the ground cable and the battery charge cable (which usually runs back to the starter lug).

 

[sam am I]

I feel I need a debate of sorts, perhaps later then.........So I will re-frame and just say NORMALLY, the ground/return of a alt is its frame.

alternator wiring - Google Search

Is the black wire just a spade lug screwed/bolted on the alt's frame? It's a redundant ground I'd guess and the "other end" c/would connect to the engine block or such if you like.

Or is the black wire it coming off the alt from a isolated stud/connection? Best check with the supplier then........wheeeew, that was close.