Install one of these Trimetric TM-2025-RV
Replace what ever converter you have with a Progressive Dynamics unit with Charge Wizard
and remote pendant
. Use only an inverter type generator
to ensure good clean power to the converter. ProgressiveDyn states on their web site you will not achieve full output if the input is dirty.
If your going to run off batteries and run a generator minimally you need something you can force into a bulk mode charge. With two GC2's and a PD9245C
I could charge up my batteries from 50% SOC in less than 4 hours with that generator on a half a gallon of fuel. In battery boondocking mode I ran with all my A/C breakers off. I would connect the generator to shore power with a proper adapter and start it with econ off. After a minute or so of warm up throw the main breaker then the converter breaker. The 45 amp charger will tug on that generator slightly but not over load it. Check the pendant, is the light on solid? No? Press and hold the button till it is and the generator may grunt again as bulk mode kicks in. By now the generator should be warmed up and you can switch it to econ mode. As the batteries charge the current will drop off and the generator will throttle down. This is your queue to go check the Trimeteric and see where your at.
P. S. If your converter is a WFCO it will never go into bulk mode and never properly charge your batteries.