Do I need a better converter?

Probably your converter is a POS.
After having 2 campers with PD converters and not knowing or caring really "why" people said WFCOs are junk, we got a camper with a WFCO. Can confirm, it's a pile of doo doo.

What is the charger and how long were you running the generator?

First morning 60% to 85%, is 25% of 200ah or 50ah. A 50amp charger should do that in around an hour.
Second morning 50% to 70%, is 20% of 200ah or 40ah. Should take 20% less charge time to get there.

Did you per chance run the generator for 1:15 the first time and 1:00 the second time?

You generally won't get to 100% charging with an hour or two on the generator (even if the charger puts out enough amps). Lead-Acid batteries start reducing the charge acceptance around 70%. At first it's a minor reduction. By the time you get to 80-90%, they accept far lower amperages, no matter how big the charger is.

If you will be boondocking another option is to get something like a 100w portable solar panel.
- Run the generator first thing in the morning to get up around 80-90% (an hour or two).
- The solar panel will peak around 8amps mid day but it will do so over several hours and top up the remaining storage.

Of course, if you do a lot of boondocking, a large permanently installed solar array is a nice option but it brings it's own set of costs/complications.

The short answer is TES !

Now would be a good time to upgrade to an inverter/charger/automatic transfer switch.

mooky stinks wrote:
Just replaced original 80ah battery with 2 100ah batteries. When dry camping for 3 nights the batteries were steadily lower after each charging during the allowed generator times. 1st night when fully charged they dropped to 60%. 2nd night they started out at 85% and dropped to 50% then 3rd was about 70% to 30%. I never saw higher than 13.7 when plugged in to my 2000watt generator. Haven’t looked at what my converter is rated for yet but am I right in thinking it’s just not putting the charge back in fast enough? Would a stand alone commercial battery charger that I have work better in the few times a year I dry camp? Any suggestions would be appreciated!

need a little more context here, what kind of batteries, what is your converter now and how long are you running the generator for.

Steve

You did not state what type of batteries you got are they FLA or LifePO4?

If it's a WFCO converter they're notorious for not going into bulk charging mode. I have 2 GC batteries and an IOTA-55 converter for faster charging off a generator.