Factory Dual Battery Setup? If not... HELP!
 

Did Mariah's ship with a Perko '1, 2, Off' dual battery setup??

I just tore into mine to start planning my Blue Sea ACR install and am completely stumped.

Port battery = Smaller of the two, has the obvious OEM heavy read cable going to terminal #1 on Perko. Also has one 10 gauge power and ground wire on the secondary battery posts.

Starboard battery = Just one positive lead to Perko terminal #2.

Perko (where it gets fun...) = One 10 gauge wire in addition to the expected 2 gauge battery cables on each terminal. One is brown with a white stripe, the other two are red. All three were butt connected about 6" down from the Perko. It looks like all three enter the main wire feed on the transom and head up the starboard side of the boat.

Soooo:

What are the additional wires on the port battery for, and what are these three mystery wires for? Where does the alternator come in? Its a very clean install so I'm wondering if this was a factory option and maybe there is a wiring diagram somewhere. I just don't get Why there would be a secondary wire on each Perko post, wouldn't that effectively provide a way to drain each battery regardless of switch position??

Re: Factory Dual Battery Setup? If not... HELP!
 

I'm no expert here. The brown w/white stripe wire may go to the bilge pump. If it is an automatic pump, as is mine, it runs direct to the battery so that it is always ready to go when needed, regardless of the switch position. I have the automatic sun pad lift. That also runs direct off the battery so that you can open it and still turn on/off the batteries to avoid other unneccesary drain.

I hope that helps some!

Re: Factory Dual Battery Setup? If not... HELP!
 

Thanks! That can help narrow things down. I was thinking about the lift last night. Makes sense that would need to be wired direct.

I really need to figure out where the charging lead from the alternator goes. I'm thinking that might be the cable going to the port battery, but then again that would mean the 2nd battery could only charge in the 'All' position. :confused:

Re: Factory Dual Battery Setup? If not... HELP!
 

The alternator typically goes back into the engine loom, and will charge the battery via the starter cable. So whatever battery / ies you have switched to the engine will get charged.

Ants

Re: Factory Dual Battery Setup? If not... HELP!
 

Thanks. With a little time with my VM I came to the same conclusion. For future users.

- 10 gauge power and ground on port battery went to trim controls.

- Brown with white strip went to bilge pump.

- One of the 10 gauge perko wires went to the dash.

I'll update later when I trace the final wire out. I plan on leaving the trim hooked up to the port battery and using it just for starting, then I'll run everything off of the starboard when I install the Blue Sea ACR.

Also, thanks to MikeT, I found out that it did come from the factory with the perko installed.