Get Home Power

I have Trawler with a single Ford layman engine and a 6kw generator.

I was trying to come up with a way to have an aux method of powering my boat if the main engine went out. I know that a 110 electric motor is probably not strong enough to power the boat.

However, is it possible to connect an electric motor to the generator and with the electric motor power a Hydraulic motor which is then connected to the main shaft:?:

 

why not. a few problems do exist though. how are you going to connect/disconect drive to and from hyd.to shaft. will gear box handle side load from drive also why lose power converting rotory power to electricity then back to rotory power, pto drive pump direct and run with geset main switch off.

 

Why bother with the hydraulics? Just use an electric motor that's suitable for your application to begin with. A 120 V motor drawing 5 kW (don't want to max out your genset for too long) draws around 42 A and puts about 6.5 hp to the propshaft. If that's not enough, you'll need a bigger genset or a second engine to do what you want to do. Hydraulics will only waste energy in this application.
Whatever you do, you will of course need some sort of combining gearbox if you want to turn the main shaft. Other options include a pulley on the shaft that you can slide a belt from the elec motor onto when you need it, or (probably a little more involved) swipe the motor from a wrecked hybrid car and put it right on the engine flywheel.

 

Thanks for your responce. I only want the motor to get me home therefore the idea of the pully on the shafe is the best way to go. I will need to determine the pullies size so that I don't kill the electric motor and or the tranmission. My only con sern is the start up amps to the motor.
Thanks again