Hello Bryce. I just received 4 Minn Kota ''Riptide Pro 101'' trolling motors and the speed controllers and propellers for my small sub. The equipment is ''off the shelf'' and matched to give good performance. The package also comes with a three year warranty.
The wiring is VERY simple. Just plug it in and go
If a problem develops, it's pretty easy to get another.
Shipped in less than a week from first order.( useful if I'm out somewhere diving and need replacements.)
The cost for one complete package was $360 plus shipping.
No thru-hull spinners, just wiring. Very easy to seal.
All the components are matched and engineered by a reputable company ( Minn Kota ) and have a long track record under use by the public.
Stainless steel construction, forward/reverse built in, and energy efficient.
Each motor is 36 volt, 46 amp max. draw at full power, and rated at about 1-1/2 hp.
The speed controllers are completely sealed in a thick coating of marine epoxy.
The whole system is designed for salt water.
This probably won't be of any use as a main drive if you plan on going 8 knots submerged in a 30 foot sub, but may be worth a look as a maneuvering thruster.
I am adding Kort nozzles to all 4 thrusters to improve thrust and protect the props and sea life.
I'm still welding the hull and windows, and hope to launch for testing early next summer.
For shallow diving ( 100 feet or less ) the motors are fine as is. When I get ready to go deeper ( 600 foot max design ) I will need to pressure compensate the motor housings with a scuba tank and regulator.
I've seen a couple of systems set up this way and it's pretty simple.
My thoughts are always on reliability.
Good luck with your project, and maybe I'll see you down under......Frank D.