Usually, boating aficionados do not consider how important the role of their boat propeller is. The propeller is the direct connection between the horsepower and the water. So when buying a propeller for your boat, be sure to make all the necessary considerations.
Finding the Right Shape and Size
Propellers are made in different shapes and sizes. In terms of propeller sizes, diameter and pitch are the two key measurements involved. First of all, the propeller pitch should be a match to the WOT (wide open throttle) range recommended by the engine manufacturer. That means you have to be able to turn the engine’s minimum rpm the engine was made for with a fully advanced throttle. An increase in a propellers pitch leads to a bigger weight or limit for the engine to drive up to greater rpm’s. A 50-horsepower engine may only be capable of turning a 15-pitch propeller, while a 750 horsepower offshore race engine can turn over 30 inches of pitch.
Checking the Diameter
Diameter is another measurement that impacts rpm capabilities as well as other boat and hull personalities. Plenty of of the diameter options have been preset for the consumer by the propeller manufacturer. In majority of low-performance applications, this works rather well. However, overall performance can be dramatically improved by fine tuning diameter. Reducing diameter will often lower rpm, and the same is true the other way around. Adjustments in diameter adjustments change the hulls’ running attitude too. Not that diameter adjustments are always necessary though, considering buyers can match stock diameters to propeller types.
Number of Blades
In theory, less blades create faster speeds. This is based on the premise that more blades create more metal in the water, thereby translating to more drag. But if a boat is running inefficiently, more blades can become an asset since the extra blade area can increase the boat’s ability to “hook up” and do better thoughout the torque band. The specific application the boat is being used in will help the operator to determine the number of blades needed to gain the best results.
Indeed, picking the right propeller for your boat can be daunting. Talking to a specialist is the most effective way of maximizing your benefits from your boat set-up, propeller included. Most will be glad to help by sharing their knowledge on the subject. It’s probably not even necessary to meet them in person. You can join online forums and get the help you need there.
Lastly, the most critical starting point is being familiar with your engine or engines capabilities. As soon as this is done, the engine package can be protected from damage due to improper rpm in connection with propping. From here, you can decide if you would like to upgrade its performance.