6 volt house batteries to start generator?

[Camper Ken]

I considering switching out my two 12volt marine/rv house batteries for two 6volt true deep cycle batteries like the Trojan T-105 or equivalent Interstate batteries.

Is it ok to use 6volt deep cycle batteries to start a generator? My coach has an Onan 5500 watt gen.

[KSCRUDE]

Yes they will start the geny but you would have to rewire everything in a series instead of the parallel you have now. You can still start the geny with just one twelve volt battery if one goes bad, not so with just one 6 volt as it takes two six volts to make 12 volts. My 13 3209 Baystar has 2 12 volts and they work great and I will never go to six volts as no need. All semi trucks back in the sixties and seventies had 4 six volt batteries wired to put out 12 volts. Since the eighties they have all gone to twelve volt batteries and some only use three batteries, but I still spec or change mine to 4 just for extra power. No way to use 3 six volt batteries to put out 12 volts but they can use 3 twelves and it saves them money!

[Camper Ken]

KSCRUDE:
Thanks for sharing your thoughts and opinion.

I also have a 2013 model 3209.

I'm switching over to 6 volt true deep cycle batteries because we dry camp the majority of the time. The factory installed 12 volt batteries on our Bay Stars work very well but don't offer the same capacity for dry camping. They're "hybrid" batteries, made for a moderate amount of deep cycling and for starting. They are ideal for a marine application, and that's exactly what it says on my 12 volt Interstate batteries ... "Marine/RV". I read your post to my other battery question, so I'm sure you're aware of this.

We installed a solar panel and are somewhat frugal with our electric use when dry camping and would rather not run the generator on a daily basis if we can avoid it.

I switched to 6 volt true deep cycle batteries on my previous motorhome and it definitely made a difference when dry camping.

Thanks again.

[Gary RVRoamer]

You can get quality 12v deep cycle batteries with capacity similar to the 6v golf cart batteries. For example, a Group 27 12v deep cycle from Trojan, the model 27TMH battery, produces 115 amp-hours, so a pair is 230, just like a pair of 6v golf cart deep cycles. The slightly larger group 30 Trojan 30XH produces 130 AH each, for a total of 260. These are true deep cycles, not marine hybrids.

However, the Trojan 12v's will probably cost you more than the 6v golf cart batteries, so it may be worthwhile to re-wire for 6v series operation.