dual engine w/ 4 batteries

[markrlindstrom]

I know this has been asked before, BUT I'm still having trouble keeping my house bank batteries (starboard side) charged when trolling with my port engine.
so,
What is the correct (and easiest) way to wire two outboards with two batteries on each engine and with a switch on each engine that has #1, #2, both and off as positions?
The house stuff is connected to the starboard bank of two batteries and I leave the switches in the "both" position allmost allways.
I was told to buy a combiner and I believe I installed it correctly, but.....
I still run down the house bank when I troll with the port engine. What gives?
I'm looking for a simple and idiot proof way to do it........if possible.
Thanks!

 

[gwwannabe]

I wouldn't be surprised if the problem is the alternator output at trolling speeds. It's not very much so you could be using more than you're producing. Before you go to a lot of trouble I would suggest hooking up some test equipment to see what you're generating and what you're using.

Gary 93 Gulfstream

 

[HaleNalu]

If you only have 2 switches then you are always going to have the chance of some issues.

A better way to do it is to get rid of the 1/both/2 switches and wire it with an individual switch for each engine, a switch for the house bank, and then a crossover emergency switch for the engines. Add to this Auto Charging Relays and you're set. House totally isolated, each engine isolated but able to charge the house.

The BEP 717-100 for dual engines combines all this into a switch cluster.

I changed the switches in my last Grady and will do the same in this one. Never a charging issue.

 

[BobP]

Add a selector switch for your ship's aux feed, so you can select what battery to use, then select the same battery as engine running so it stays charged.

I added a 3rd battery this year, so when running have two series 29s in parralel (both position) for one motor and one series 27 for other motor, at dock seperate the three batteries so the three (3) output battery charger can do it's thing.

As I expected, no electronics restarts when I start motor or hit SW washdown pump, as was the case before. Pain in can especially with radar since about 45 seconds is needed to warm it up each time.

I run ship's aux from the two 29s in parralel (that's why it works). And have no more than two 1/2/both/off switches and didn' have to add the optional Yamaha charge feeder outputs.

I like it simple and not having batteries paralleled with each other (all the time), and ability to charge each battery as unique.

 

[Capt. Ed]

How many battery switches do you have now? You have two banks of batteries and you should have two switches, one for each bank. Could be as simple as adding a second switch. Hope this helps.