89 340da port battery cable?

[Searay-Bob]

On my 1989 340DA the port battery was taken out last fall I put a new one in today and there are 3 cables that go to it:smt013 I know that the red on goes to the positive and the one black one goes to the neg so where does the other wire that goes onto the bolt go? Neg or pos?:smt100
Thanks
Bob

 

[JVM225]

It probably powers some other accessory. Maybe even the bilge pump(s)?
Anything is possible, but I'd bet on the positive side since things don't usually get ground from the battery posts.

 

[wileecoyote]

Sorry, I have the same problem remembering what goes where everytime I put them back in. Someone may correct me, but I believe there is a cable that goes from the bolt on one battery to the positive post on the other battery.

 

[KRB64]

Sorry, I have the same problem remembering what goes where everytime I put them back in. Someone may correct me, but I believe there is a cable that goes from the bolt on one battery to the positive post on the other battery.

I use the blue masking tape to lable wires when I pull them off. Better yet, use a label maker for permanent ID.

IF you have double batteries and want to run them together then you'd go from pos post to pos post unless you were 24V.

Most likely it is like JVM said and is a constant hot for a bilge pump or similar. Assuming it is a small gauge wire (thus likely not an engine ground), you could leave it off and then see what doesn't work...

JVM - on a boat, if things don't get grounded from a battery post, where do they? The motor or is there a ground block somewhere? (Its the wee hours of the weekend and coffee hasn't kicked in yet...)

 

[Searay-Bob]

I didn't take the battery out it was out when I got the boat. It is a heavy guage wire and it looks like a ground. It runs toward the front of the boat. It's Black so I think it is a ground. Won't hurt to hook it up to the ground and see what happens.
Bob

 

[kybishop]

If you have a battery selector switch, usually one heavy cable runs to that. For selecting the battery to both off, battery one or battery 2. Depending which battery runs to it and where the switch is located and if you have one.

I put an extra battery and selector switch on the 82 cuddy but I can not remember now exactly which cable went to it...I would have to look.

KB

 

[JVM225]

I use the blue masking tape to lable wires when I pull them off. Better yet, use a label maker for permanent ID.


JVM - on a boat, if things don't get grounded from a battery post, where do they? The motor or is there a ground block somewhere? (Its the wee hours of the weekend and coffee hasn't kicked in yet...)

The motor is a good place. There is also a grounding block on the bottom of my boat.