Last year, we converted a small outboard to electric power. We ended up with a Etek clone (MARS), a AXE controller, 48V car battery system but it was on top of a B&S electric outboard base (the previous owner had stripped the motor out). The boat was a 18ft homebuilt garvey flats and to say it was inefficient is being kind. We can run about 1 hr all out and even that gets about 6mph. (105ah batteries). Deep cycle (thats what I had). My guess is that since the outboard was built for 5hp, pushing with 10 was ineffective (prop size)
We are about to build a Bolger Sneakeasy. James M Rudholm built one with electric power, but sadly, his web site seems to have gone away, which is terrible for me since I was hoping to lift his experience.
Looks like the Sneakeasy was getting 12mph on 8hp gas. If I look at the charts, I should get about 10 on my 48V ETEK. But I'd like to get a longer running time. About 2 hours is where I need to be. But... there are lots of other factors that I can balance so I need some guidance.
We are using a 25hp outboard as a base (10in prop) but we have rigged a pulley drive to the motor. Since cruising speed is more important to me that pure speed, any feel for the optimum prop speed ?
Since I can gear up or down the motor. My inclination was to get speed up the prop but should I allow the motor to turn faster and the prop slower ? Whats the current best thinking ?
Mr Rudholm used 8- 6v batteries, given my setup, any recommendations on battery ? My westmarine deep cycle were "free" but now that I have authority to buy new ones, any thoughts ? Go Carts batteries ? Car ? What ? I've read a lot of the posts and nominally more confused than illuminated.
Thanks
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