The methods of propulsion I've seen so far seem to be mostly trolling
motors. That goes along with the tried and true. It also seems the least
expensive, easiest to install, and probably the easiest to fix/maintain. Not
having any REAL experience, I'm just relaying my thoughts so far. I have seen
some good applications though. One guy used scuba tanks and regulator to
pressurize the motors. Looked pretty simple to install, and seemed to make
sense. The other method I've heard about is oil filled motors. As I understand
it, a fitting is installed in the motor housing and a flexible tube is attached
and sealed after filling the motor and tube with light oil. As the assembly goes
down and is exposed to greater pressure, the flexible hose is squeezed and
maintains equal pressure with the surrounding water. Sounds too simple but it
should work. Does anybody have any more info on this?
I like the idea of having wires in a thru-hull versus a larger hole with
hydraulic oil and the maintenance that would entail. The electric thru-hull
connectors are certified to something really deep, have prongs to pull the wires
off, and with a ball valve on there, any leak would be shut off quickly. Here's
an idea....how about using air motors to drive a prop. Like maybe using a
modified air-tool motor ( grinder, drill, etc.) Some of them run at very high
speeds, it would be a pressurized system, and you could carry extra air bottles
instead of having to spend all nite recharging your batteries.Maybe I'll dunk
one of my tools and see what happens.