[prairieschooner]

Lets get Clarke to get some pics when he can. It will be a few days before I can get to our '82.
as I stated earlier the Battery Banks on our '82 are separated making the Engine Batteries getting Charged by the Alternators. The House Bank is Charged by the HEART Power Inverter. The only way to charge the House Batteries with the Alternators is to use the Merge Switch. The only way to Charge the Engine Batteries with the Power Inverter is to use the Merge Switch.
Since you are now having a problem with the Engine Batteries, I would suggest that you charge the Engine Batteries, then Disconnect them (by removing the cables) for a day or two and check them again, this will help you know if the battery is bad). You should also do the same with the House Batteries to prove or disprove them.
Again, if I use the Merge Switch and then shut the coach down the batteries stay merged until the switch is turned off, or the merge function does not stop after the engine is turned off (using the Ignition Switch).
I have a clamp on DC Amp Meter so I would use it to see if there was a power drain to ensure that something isn't draining the Batteries. I just found that there was a problem with one of the Clocks and it was draining the battery with a 5 Amp continuous drain, after finding the problem it was disconnected.