All about Aeroncas on floats
Likewise, I would suggest nothing less than 85 hp. I have a 100 hp and with two people plus a load of fuel it's about right. The 90HP performs just as well as the 100HP I'm told with the right prop. The bonus with the larger engines is electric start which makes life a lot easier on the water. To help reduce the additional weght I added a lite weight starter and battery. I think you would have a one person aircraft with 65 HP.