The propeller is a critical factor to consider when upgrading or repairing your recreational motorboat. Basically, this component is constructed as a fan mechanism that converts the normal rotation into thrust. In simple terms, when the fan blades rotate, more power will be generated for the boat. Therefore, it is important to select the right propeller in order to improve acceleration performance, increase general performance and reduce engine strain. Here are the primary aspects that you should consider when purchasing a replacement propeller for your mercruiser motor boat.

Propeller Size

The propeller size is determined by two crucial aspects: diameter and pitch. The diameter is essentially twice the length from the centre of the propeller to the tip of one of the blades. This will determine the area covered when the component is rotating. You should choose the original size recommended by the manufacturer because the diameter is selected to match the engine power. The pitch refers to the distance covered by the propeller when the component makes one complete revolution. If you choose a higher pitch for your replacement propeller, you will improve your motorboat speed. However, if the increase is too large, the upgrade might result in engine strain and subsequent premature wear.

Propeller Materials

There are different materials utilised in the fabrication of a motorboat propeller. You should assess and compare your options to ensure that your ultimate choice matches your budget, performance requirements and preferences. The aluminium propeller is the common choice for recreational boat owners. It is an affordable choice and the product is available in diverse sizes, styles and models. Unfortunately, the lightweight nature of the material makes it unsuitable for heavy applications.

Composite propellers are becoming more popular in the market as alternatives to aluminium. These can be made from diverse materials, but the fibreglass and nylon blend is the most notable. The blades are stronger and less susceptible to damage, but the centre part is often made using aluminium. Stainless steel propellers are durable and perform exceptionally in heavy-duty applications. However, the high cost of purchase can be a limiting factor for recreational boaters.

Number of Blades

Boat propellers are constructed with different numbers of blades, but three or four are the most popular options. The standard three-blade design is appropriate for general purpose boating and is available in diverse sizes to suit all motorboats. The four-blade style provides more stability and performance in rougher waters has better handling at low speeds. Unfortunately, sizes are limited since the demand is low and the purchase price is higher.