'Dual input' emergency drive gearbox.

[rustybarge]

Hi All,


Came me across this interesting ' get you home' standby drive system made in the USA, 'continuous use' rated, works on the main prop shaft. http://www.keypower.net/catalog/item/8567340/9434797.htm

Seems a much better idea than a wing engine?

 

[sarabande]

but it seems to require an engine to power it with hydraulics... And not a small engine; they want 40 to 75 HP.

Probably fine if you have a BIG generator with a hydraulic pump for emergencies, but then why not have a co-axial electric motor as a standby motive power, to drive the shaft with a chain drive.

 

[rustybarge]

but it seems to require an engine to power it with hydraulics... And not a small engine; they want 40 to 75 HP.

Probably fine if you have a BIG generator with a hydraulic pump for emergencies, but then why not have a co-axial electric motor as a standby motive power, to drive the shaft with a chain drive.

A 40 or 50ft boat will probably need 75hp to push it along at 7 or 8kts. i suppose the hydraulic motor on the gearbox means you could locate your standby engine anywhere convenient to keep the boat in trim..

A chain drive is a good idea, but would the gearbox on the standby engine like being continuously driven by the main engine while being in neutral?
likewise the main gearbox when the standby is in gear?