[spareparts]

thats giving a jet ski more credit than they deserve. the problem with jetpumps is they are too efficient, as the speed increases, the amount of water that enters the inlet increases, so the pump becomes more efficient in pumping the water out, *a prop usually slips some what, allowing the engine to keep turning up. Most jetpumps will bog an engine, they require tons of torque, unless you make them slip by using lots of clearance in the pump( jetski type), that allows the eninge to rev up to the higher rpm where it makes power. Some pumps have a rudder, but it doesnt help at low speed.

Check out a Hinkley Picnic Boat( 3/4 mil 34' dayboat), they use a Hamilton Jet pump hooked to a Yanmar Diesel. The low speed handleing on these suck so bad, they incorporated a computerized joystick hooked to the pump, engine, and bow thruster, this thing came make anyone dock a boat like a pro