1 battery, 2 motors
 

Can 1 starting battery be used for 2 motors?
1 motor will be used to keep it charged, while the alt. wire off the 2nd motor will be used to charge 2 house batteries. The 2house and starting batteries will be isolated from each other.
Just want to make sure the starting battery motor alt doesn't get fried when the 2nd motor is started.
Thanks.

hmmmm thats an interesting question and it got me thinking......at first i thought no cause the amp load on the Alt could fry it....then i thought....thats exactly whats going on when you jump start another car! You are putting another load on you starting battery and alt and its no problem! So as long as you isolate the second alternator it should be no problem at all!

Not a bad idea, I am assuming you are triyng to do this for accessory purposes?

The only porblem I see is common ground. I would assume you are removing all wires from the starter post to isolate the second engine. Now your electronics for that engine are going to be running off the house battery. Ign, dash, volt meter ect. These are grounded off your engine, but your engine will need to have a good ground to the start battery in order to start.

I have never seen in done, and I am not an electrical engineer....however I know why you want to do it :D

And to answer your question, the alt should be just fine.

This for my cruiser.

I see no reason for 2 dedicated starting batteries just to start the motors. Battery switches allow for emergency switching if needed.
As it is now, I have 2 deepcyle batteries that do both start/house. I want the sep battery just for starting so I don't have to worry about dead batteries for nites out on the water. lites, tunes, invertor, refridge, electric head, etc....

Yes, simply pulling only the alt wire off 1 starter solenoid to feed the 2 house batteries was my plan, leaving the heavy battery cable intact. I did not think about the electronics aspect by doing so. In all fairness, that may not be a problem since that is how it works now, I'd just be using the other battery to supply juice to start. I'd also be connecting a charging relay between the house bank and starting battery so with the motors running, both alt would be charging all 3 batteries equally, vs relying on just the altered alt wire to charge 2 batteries. Normally I wouldn't think it an issue to do so, but the house will naturally see the largest draw down and require more recharging resources. Might be stressing the 1 (house) alt while the non altered alt (starting) is free wheeling 99% of time. At least on paper I think so.

Thats what Formula does, Our 382 only has two batterys one house one starting.:coolcowboy:

How is the house battery charged, isolaters?
Thanks

Yes !!!

Motor coaches are set up this way. Mine has 2 starting, 4 house with a battery isolator,(basically a very large diode) to keep from backfeeding.


Darrell.