Adding 2nd house battery

[walt bowen]

I have a 2001 263 w/twin 200 hpdi's and a single cranking battery for each motor and the starboard motor and batt. power most of the house stuff and the port is pretty much just the motor and battery. To keep from draining the house battery as much my thought is just to add an additional house battery in parallel w/my current house batt.. My two current batts are 2yrs. old, they are Deka's-24 cranking batts., my thought was to just add one more of the exact. same, but the guy at boaters world did mention that it is best if the house batt. is a deep cycle which seems to make sense, but mine are in good shape and I'm fairly sure you shouldn't mix the cranking and deep cycle. Any experience or advice would be much appreciated.

Walt Bowen
2001 263 Chase
w/200 hpdi's

 

[Grog]

Go for the deep cycle for the house battery grp 27 or 31 if you can fit it. Crank and deep cell are both wet cell batteries, just designed differently. You can use the ACR (automatic charging relay) or if your engine has it, the second charging leads.

 

[BobP]

Alternately, you can make a slight change so your two existing batteries can back each other up for the house load, which you say is only supplied from one battery. Then you can have the house load 1/2 the day on one batt then switch to the other.

If you now have (two) OFF, 1,2 BOTH Battery switches, you connect the house load feeder to the same stud of the battery switch as one of your engines is, either one. Then you can swap over the load. When you do make the swap, the engine will also be swapped to the other battery, so you do the same altrenate swap for the other engine so the two engines at not on same battery.

This will cost nothing to setup, and may work for you, otherwise figure about three hundred for the third battery installation if you do it yourself.

If you do as you propose to add a third battery for house load, what will you do if it runs down and you need a backup?