AQUASUB

What Nick is saying is perfectly correct ,its Skip trying as usual to say that it is not,my motors and drives are very similar.
A ball bearing 3.5 to one gearbox maid by Master Airscrew and a stsndard 12 vdc can motor RS or HS 550 and 2.5 3 bladed moderate pitch prop does the trick ,very simple inexpensive and lasts a very long time especialy water cooled for sub use natuaraly.Even on a boat it would run very well.
I have tried hundreds of diferent motors and the good old standard Johnson or Mabuchi has never let me down I garrantee it!
The pics show the gear case and the complete unit,this one is the special Aquadrive one I call it ,there is a gear pump on the other end of the motor that has an extended shaft that just so happens to be the right size for the pump!
Most of my subs use a pump that is driven from the main shaft in a sealed continues loop of 2 coils and a mixture of water and any freez to lube the pump and prevent corrotion.
Dave