Re: Typical isolating diode location?
In the O'Day 302 case, I think the charging line (from the alternator) goes up to the master disconnect in the electrical panel, and the diode(s) are downstream of that. The manual says both batteries will charge even if the master is in the '1' or '2' position ('both' not required), so that indicates to me that they have to be past that point.
I may just run the alternator direct to the batteries with a 'engine disconnect' switch and fused link added for safety. This would be another way to remove the undesired voltage drop I'm observing to the batteries when charging.