Like anything, there are choices to make when it comes to buying a boat propeller. Just like everything else, you will need to shop for that item that meets your needs and your price point at the same time. Even once you determine the horsepower you need, there are several other choices to make. Being an informed buyer will help you save time and get the right boat prop for your needs.
Boat props made of plastic are generally reserved for emergency situations, so if your looking for your primary motor, keep going. Aluminum props are relatively inexpensive, and they should last several seasons if you take care of them. Stainless Steel props are the most expensive. The advantage here is strength, durability, and greater thrust efficiency due to rigid blades. As usual, you get what you pay for.
Besides horsepower, you need to determine what pitch you need. Boat Props are classified diameter x pitch. So a 13x21 prop is 13 inches in diameter by 21 inches pitch. The diameter refers to the size of the propeller from blade tip to blade tip. The pitch is the distance forward that the propeller will travel in one 360 degree turn.
Pitch is an important factor to understand when buying a motor. What you want will depend on what boat you have and what you will be using it for. Because props basically operate in a single gear, choosing the right pitch is how you achieve a balance between speed and acceleration. If you currently have a prop on your boat, you can test it for pitch by cruising at full throttle and watching the RPM red line. You want to do this with at full trim and with a light load. A prop that is the right size for your boat should level out about 100 -200 RPMs below the upper limit.
Prepared with this knowledge, you can determine which pitch to buy by comparing it the current prop. The rule of thumb is that each inch of pitch change comes out to about an 150-200 RPM difference. If you need higher RPMs, buy a lower pitch. Less RPMs, a higher one. Once you have a rough idea of what you need, it's time to talk to a retailer or poke around online. It won't be hard now to pick out the right prop for whatever kind of boating you have in mind.
The experts at Propeller Depot will be able to assist you in finding the perfect propeller for your boat, at the absolute lowest cost. If you have any boat prop questions, reach out to the boating experts at Propeller Depot today.
