Basic Water Jet Propulsion Systems for Boats

by Charles Pearson
Jet propulsion boats are becoming more common than other kinds of boats.

Jet propulsion boats are becoming more common than other kinds of boats.

Boats use either propellers, oars, sails or jets of water to move the boat through the water. Most modern boats use jet propulsion systems. The jets of water provide the greatest degree of power for the boat. These jet propulsion systems do not have many of the maintenance requirements of other systems.


Water shoots out of the back of the boat, which creates an action that is met with an equal and opposite reaction, based on Newtonian physics. Gasoline or diesel powers a water pump, which builds up pressure and then allows the boat to release that pressure, creating the force needed to power the boat. The nozzle that releases the water can turn in different directions. A deflector reverses the direction of the thrust of the nozzle, pushing the boat in the opposite direction. The jet propulsion system is safer, more economical, maneuverable and environmentally friendly than the propeller system. The propeller system can accidentally injure those in the water by cutting them with the blades. The jet propulsion system, on the other hand, has a much lower chance of harming those in the water. The only possible injury comes from the water stream pushing a piece of debris into someone.


Jet propulsion systems also require less maintenance and little calibration. Those with propeller systems must frequently check the propellers to make sure that they have the right alignment so that the boat gets the maximum efficiency and does not sustain damage. Also, propellers must be sharpened so that they can effectively cut the water. Jet propulsion systems only have problems if the nozzle gets damaged or warped, which only leads to a nozzle replacement.


Engines can very easily power the jet propulsion system without a lot of strain placed on the engine. Still, owners must make sure that the engine has proper lubrication when operating the engine. Most of the maintenance for the jet propulsion system is based on maintaining the jet engine fluids. When heavier repairs are needed, the boat owner can normally detach the defective part and either replace it or take it into a shop for repairs, eliminating the need to haul the boat.


Jet propulsion systems do not produce as much noise as the propeller systems and they do not create as much vibration. These features make the system more comfortable for those riding in the boat for recreational purposes. Also, the lower degree of vibration puts less strain on the boat, reducing the frequency of maintenance.

About the Author

Charles Pearson has written as a freelancer since 2009. He has a B.S. in literature from Purdue University Calumet and is currently working on his M.A. He has written the ebooks "Karate You Can Teach Your Kids," "Macadamia Growing Handout" and "The Raw Food Diet."

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