Best Marine Boat Outboard Propellers

Posted by Author David Lee

Choosing Right Propeller For Your Boat

Propellers are crucial to optimum performance and life of your outboard engine. The propeller is where the power meets the water, so it's important to choose the correct propeller to achieve the outboards full potential. Finding the right propeller for a boat and outboard combination is normally a matter of trial and error. There are many variables to consider. Both design, weight, load distribution, the outboards running characteristics and how and where the boat will be used, all influence the propeller choice. Performance reports are developed through factory boat and outboard testing. they can provide valuable information to begin testing your boat and outboard. Evinrude engineers develop propellers to provide the best propeller match for different boats and outboard combinations. See your dealer for the most up-to-date propeller models. Your dealer or the boat's manufacturer may offer recommendations based on their experiences. One of the first decisions to make is a choice of material. Aluminum propellers offer good performance at a low cost for most applications. Stainless steel propellers are more expensive than aluminum but they're more durable and they're thinner blades provide better performance. A second decision is blade count. Most propellers have either three or four blades. Three blades are typically more efficient but four blades generally provide a better grip on the water especially in tight turns or rough water. After you decide which model propeller to use you need to determine a crucial dimension. In the center or hub of the propeller you'll find a number – for example 14 and 3/4 by 17. The first number 14 and 3/4 is the diameter of the propeller measured in inches at the tips of the blade. The diameter is generally determined by the propeller model. The second number 17 is the pitch. This is a dimension you need to determine. Pitch is the distance the propeller would travel in one revolution if it was cutting through a solid such as gelatin. Of course water isn't solid and the propeller will slip a little bit but not as much as you might expect. A good outboard and propeller combination will generally slip less than ten percent and maybe only a couple of percent. Lower pitch propellers allow the outboard should build up RPMs quickly which is helpful for big boats and heavy loads. But they create less forward travel with each revolution and slower top speeds. Higher pitch propellers produce less low-speed pulling power and acceleration but more top-end speed. For best performance and fuel economy you must determine the correct pitch propeller for your boats and outboard combination. Use the boat builders recommendation only as a starting point. Your dealer may also be able to help. But an on the water test is the only way to determine the correct pitch. You will need access to different pitch propellers for the propeller model you have chosen. Your dealer may have demonstration propellers available. The outboard comes with all the necessary propeller attaching hardware. If the propeller comes with its own hardware use it instead. Using the wrong hardware can damage the propeller or gear case. Refer to the installation procedure in the operator's guide, lubricate the propeller shaft with triple guard grease so the propeller can be removed later. Position and orient washers and spacers correctly. Tighten the nut to the in the operators manual. Use a block of wood to prevent the propeller from churning. Be careful as many propellers have sharp edges. Secure the nut with a retainer and cotterpin. Install all drain plugs. Launch the boat. Wear a personal floatation device or PFD when running the boat. Always connect a tether cord to the outboard cutoff switch and secure it to your clothing or PFD. Accurate tachometer readings are essential. If possible use a tachometer as it will be most accurate. Navigate to a safe area for a high-speed run. Accelerate to full throttle trim out the outboard and observe the RPM. The outboard should run near the midpoint of the recommended full throttle RPM operating range with a normal load in the boat. If you have less than a normal load, for instance less people or equipment, or if you're testing on a cool day, the outboard should run near the top of the RPM range. The outboard will produce less power on a hot humid day because the air is not as dense. Accelerate the boat onto a plane several times. Check performance at various trim angle adjusting rod positions or power trim positions. To find the optimum trim position, trim the outboard up until the RPM increases with no corresponding increase in speed, then trim down slightly. You may need to try different propellers to achieve the optimum RPM at full throttle. If the RPM is too high try a higher pitch propeller, if it's too low try a lower pitch propeller. For best results you should try to achieve the outboards optimum RPM range which is a narrower RPM range than the wide-open throttle range your.

3 Blade vs 4 Blade Propellers | What’s the Difference Between 3 and 4 Blade Outboard Props

We're gonna spend a little bit of time comparing a three blade to prop to a four blade prop. Now when should you choose one or the other? Well that's kind of a loaded question. What type of application are you actually using it for? We all know that probably 90% of the boats out there all have the three-blade propeller, so why would you want to go to a four blade? Well the short answer is the four blade has more surface area and then it has more bite, and that will allow the boat to get up on a plane and then maintain that plane easier at a lower rpm. With the three blade, it actually has less surface area, less drag, and it'll offer more top speed than a four blade will. So when does a four blades ability really come into play? Well think about it: if you're out on the ocean, the conditions are constantly changing and there's hardly ever a time where you can run flat out all the time. So if you've got a larger boat, then a four blade may be the answer to your problem. Because when the seas get rough, and you need a lot of control, you need more bite to actually be able to maintain the boat in the correct direction and to keep it in the correct speed. Another reason you may want to consider switching from a three to a four blade is, well, as time goes on sometimes the way you use a boat and what you have on it, they change. Let's face it: when you first bought your boat it may not have had all the options that you've added to it over the years. Maybe you added an extra live well or an extra water tank to wash down the decks when you were through for the day. Now all those changes? That ends up adding a lot of weight to your boat over time, and if you go back and think about it, you've probably put more on your boat than you remember. Now maybe the time that you need to switch from the three blade up to a four blade to get that extra oomph to get your boat out of the water and on a plane faster and in it more easily. So the decision is pretty simple. Honestly, the three blade is going to cover 90% of the conditions out there. But if you find yourself spending more time in the mid-range and the lower speeds? Maybe your boat weighs a little bit more than when you started it, you're looking for more control and more lift to get it out of the water? Then you may want to consider going to a four-blade set up. You're gonna lose a little bit of top-end speed that you're gonna have with the three blade, but you're gonna have a lot more control and lift with a four blade. is a source where the post Marine Boat Outboard Propellers appeared first.

Leave a Reply

Your email address will not be published. Required fields are marked *