I built all welded aluminum boats for several years. Built about 75 boats from 14'-17'. The boats were all flat bottom bateau style and most were equipped with stick steering. The customers until the last 2 years I built powered the boats after they bought it with their choice of power. I had 2 customers who powered with Honda engines (the only 2 equipped with Hondas). Both of those boats have had severe electrolysis issues, to point the boats have had to have numerous hull repairs. Both of the boats are trailer boats, used mainly in fresh water but will fish some in brackish water, but the boats are not left in the water. Both owners told me they anodes on the engines have to be replaced yearly, but they have been unable to locate any stray current running through the hull. AT the time I was building the nearest Honda dealer was over 100 miles away is the only reason those were the only 2 equipped with Hondas. None of the other boats have reported any such issues with their boats. The other boats are equipped almost equally between OMCs, earlier year etecs, Mercs, Yamis and Suzukis. Both of the motors are around 02-05 models. I know at one time Honda had some corrosion issues on some saltwater applications but I thought those issues had been corrected in the early 2000s. Any body have any idea what could be causing the issue?