Getting your boat ready for winter
How to find the right size Outboard Motor Propeller
For outboard motor propellers, if your boat has a working tachometer than you can follow the same procedures outlined in our previous blog dealing with sterndrive boats. Using a tachometer is the best way to find the right size boat propellers. What if you don’t have a tachometer on your boat? This is very common if you have a small boat with a low horsepower outboard motor on it.
First if you have an outboard motor with no power trim you do have a mechanical trim position pin system on your transom bracket on the engine that gives you about four to six trim position options that you can adjust simply by putting the pin in the different position holes yourself and then test driving the boat and see how the boat rides underway at speed.
Find the right trim position that gives you the best performance that you like.
It is advised to get a remote tachometer hooked up to your outboard engine and see what your RPMs are at full speed if at all possible. Without a tachometer the best way to find the best size boat prop for your boat is to first know what diameter and pitch size propeller is on your motor then see how it gets up on plane from a standing start with just you in the boat and a light load in the boat. If it seems slow to take off that usually indicates you probably have low RPMs at full throttle and need to go down in pitch size one or two inches in pitch in order to get a quicker take off and increase RPMs. If your boat jumps up on plane really fast you might have too high RPMs at full throttle, then you could probably go up in pitch one or two inches. This will make your boat a little slower to take off but it might save you from causing damage to your motor from over revving your engine at ful throttle. If in your opinion it takes off OK then you probably have the size right boat prop.
This method without using a tachometer is not super accurate but it should help you to get at least close to having the right size boat propeller.
We offer a wide variety of boat propellers for most modern engines at some of the lowest prices anywhere.
How you can find the right size boat propeller
Boat propellers are a big mystery to a lot of boat owners. But determining what size boat propeller you need to use for your boat and motor combination is not as complicated as you might think. There are just a few simple things you need to know and a few things you might need to find out that you can do yourself.
If you haven’t read our two previous blogs, Looking for a new boat prop? and Looking for a new boat prop? Part two, please do so for the basic information about diameter and pitch.
What you need to know is every engine has an RPM ( revolutions per minute ) range that you need to stay with in for safe engine operation, at full speed or also called wide open throttle ( WOT ) trimmed up if equiped with power trim. All sterndrive engine drive systems have power trim and tilt and most of them have tachometer gauges that show what the RPMS your engine is producing so what you need to know is what diameter and pitch boat prop you have and what your WOT RPM range is for your engine, the range can be found in your engine owners manual or ask your local service dealer that works on your engine brand what your range is.Then take your boat out with just you in it and with a light load, go full speed with it and play with the trim going up as far as you can that produces the fastest speed attainable without trimming up too much then look and see what your RPM’s are. The RPM range is about four to six hundred RPM’s. If the range for your egine is 4400 to 4800 RPMs and you are reading 4700 RPMs then you have the right pitch prop. If you are getting over 4800 RPMs you need a 23 pitchthree blade prop. If you are getting less than 4400 RPMs you need a 19 pitch three blade prop. Your engine’s horsepower is rated maximum horsepower at about 4700 RPMs, that is the RPM number you try to achieve. If your prop is an aluminum 21 pitch three blade propeller and you want a spare get the same size prop. If you want to pull tubers and skiers get a four blade 19 pitch prop for better takeoffs and better pulling performance. A four bladed 19 pitch prop will produce about the same RPMs as a 21 pitch three blade boat propeller. The same goes for stainless steel propellers RPM wise with just a little less RPMs than aluminum propellers, maybe two or three hundred in either the three or four blade because an aluminum 21 pitch boat prop is closer to a 20 under load because the blades will bend a little in aluminum and stainless steel prop blades don’t bend under load.
Next blog will be how to size boat propellers for outboard motors.
For the best prices on hundreds of boat props please visit our boat propeller website or call us at 1-800-573-5533
Looking for a New Boat Prop ? PART TWO
When you see how boat propellers are described in terms of size it is done with actually showing two sizes for one boat prop. Example: 14 1/5 x 19. The first number is the diameter of the propeller measured from the center of the prop shaft hole of the prop where the prop shaft goes into out to one blade tip then doubled. If you measured seven and one quarter inches on your prop then the diameter of your prop is 14 1/2 inches. Simple.
How you measure the pitch of a boat propeller is a little more complicated. How do you measure the performance of a boat propeller when it is used in a liquid?
The answer is you really can’t. Boat propeller makers then determined that the best way to measure performance was not do it using water because that could be nearly impossible but to see how the prop motion would react going thru a solid. The pitch is how far a boat prop will travel thru a solid one revolution theoretically, measured in terms of inches. A 19 pitch prop should go 19 inches forward one turn. In water how to see the amount of slippage that is happening because the prop can’t get a good grip on water would be extremely hard to measure. The degree of slippage is much easier see and to improve on using the solid model. Using a solid as a model is also much more accurate when designing and making boat propellers that will work the best. You need a variety of prop pitches that work differently from each other because just one pitch size is not going to work for every size boat and motor combination. The degree of slippage is much easier to improve on using the solid model.
For the best performing boat propellers at the best prices check out our website or call us at 1-800-573-5533
Looking for a new boat prop ?
When you start looking for a new boat prop you go on-line and search boat propellers to see what is available for your engine. If you have never bought a boat propeller before you will see that the sizes are shown with two numbers not just one. You will see 10 1/8 x 14 or 14.5 x 19 and a bunch of other sizes that make you wonder what do these numbers mean? Well it is really very simple. The first number is the diameter of the boat propeller and the second number is the pitch. First I’ll give a brief definition of pitch and the rest of this blog will focus on diameter.
The next blog will be about pitch. The easiest explanation about pitch is that it is how far a propeller will travel forward through a solid one revolution in terms of inches. A 14 pitch prop will go 14 inches forward in one turn and a 19 pitch prop will go 19 inches forward in one turn.The definition of a boat propellers diameter is a measurement from the center of the propeller shaft hole in the center of the prop out to one blade tip then multiplied by two. For example, if you measured from the center out to one tip and got a measurement of five and one sixteenth inches then the diameter of you propeller is 10 1/8 inches. If you measured seven and one quarter inches then you have a 14. 5 diameter prop.
The smaller the outboard motor in terms of horsepower, the smaller the diameter of the boat prop is. And the bigger the motor is the bigger the diameter of the prop is. The reason for this is that you cannot use a huge diameter prop on say a twenty horsepower engine because it would be trying to bite way too much water for the little horsepower engine to handle and it would bog down the engine so much that the boat would hardly move. The opposite effect would happen if you put a real small diameter boat propeller on a large horsepower engine. The prop would just pretty much free spin at a high rate of speed because it’s not biting enough water to push the boat and the engine would rev way up and the boat would hardly move.
What diameters work best for what engines and for different pitches is determined by the propeller manufacturer through research and development witch means just trial and error on what diameter gives the best performance for a certain pitch.
For more information on boat propellers and to place orders please check out our website. Or call us a 1-800-573-5533
Turning Point Stainless Steel Propellers
Turning Point Safer Boat Propellers – Aegis Model
Turning Point safer boat propellers were developed since every year there are thousands of injuries and even deaths caused by boat propellers cutting people and sea life in all kinds of waterways.
Many injuries happen to people who are in the water behind the boat and close to the boat propeller when the driver puts the propeller in gear to get under way not realizing someone is back there and they are run over and cut up. Regular boat propellers can cause very severe cuts because it is spinning so fast.
Turning Point Propellers has teamed up with Colin Chamberlain the inventor of the ESP Safer Prop and is now offering boat props that can minimize the damage of these propeller strikes at low speeds to people, marine mammals, turtles and other sea life. This new model line is the result of ten years of intensive research and development and are called Aegis Propellers. They are stainless steel propellers that have a green multi-coat paint finish for better visibility under water. Under the green coat they have a red coat that shows when the propeller gets damaged and the green paint is scraped off. This is a great visual aid to see that damage has occurred to the boat prop.
These new boat props are available a variety of sizes for 25 horsepower bigfoot outboards all the way up to 300 plus horsepower outboards and sterndrives in all engine brands. They are all three bladed right hand rotation stainless steel props.
Please see our safer boat propellers website for the best prices on hundreds of boat propellers in aluminum and stainless steel or call us at 1-800-573-5533 for recommendations.
Boat Propellers Educational Information
When looking to buy a new boat propeller and want to know about the boat propulsion system use on your boat – use our Boat Propellers Educational Information. Over the years that people looking to buy a new boat propeller are becoming less and less knowledgeable about their boat’s propulsion system be it an outboard motor or a sterndrive.
It’s simply because the mechanical age is vanishing and the technological age is now in full swing. In the past a lot more people actually worked on their boats and cars because they were a lot simpler to work on than the much more complicated stuff we have today.
Boat owners with little knowledge about mechanical things should still try to learn at least a little bit how their boat works and how boat propellers work.
We have a vast amount of information on boat props starting with our boat Propellers Education Section on the lower part of our home page.
Hub kits are explained and then we tell you the basics on how to determine what size boat prop you should be using on your boat. We then explain aluminum propellers and stainless steel propellers and also about three, four and five blade boat propellers
We also have many other pages with information on boat props such as our Propellers 101 page that tells you all about the characteristics of a boat prop like what is pitch and what is cupping etc. And our Propeller Basics page that gives additional propeller information such as what cavitation is and it also shows illustrations of the different propeller topics listed.
We believe that if you are a boat owner this information on our website should be looked at so you are more aware about how your boat propeller should work.
We have the lowest prices on hundreds of boat propellers in all brands and ship same day if ordered early enough or the next day via UPS or FEDEX. You can also call us during business hours at 1-800-573-5533 for expert recommendations.
Using our Boat Propellers for Sale Website
Our website offers many brands of boat propellers for sale and we think it is very user friendly with easy navigation. We also have numerous pages giving great expert information and articles all about boat props.
It all starts on our home page. On the top of the page we tell you a little about ourselves and that we are in our twentieth year of being one of the largest dealers on the internet and that we have the lowest prices on hundreds of aluminum propellers and stainless steel propellers that you can order online paying with a credit card or using a PayPal account, or you can order by phone. Just below this erea we show all the propeller brands highlighted in blue that you click on to go to the brands section where you can easily get information on that brand and what propellers you can choose from for your engine. A side bar is shown listing everything so you can easily go to the other brands and items. The rest of the home page gives our phone number so you can call us and get expert advice and place an order if you do not want to order online.
Then below that we show you all the great information on what propeller you can use and other options for types of boat props you might want to consider. We have dozens of boat prop articles on our blog page and have pages like “Boat Propellers 101” and “Boat Propeller Basics” that give you basic information. We are absolutely an authority source on boat propellers.
On our Solas Propellers section you can use the “Prop Finder” tool to find the right Solas boat prop for you and also on the Turning Point Propellers section there is a “Prop Wizard” that does the same thing for you about Turning Point propellers.
If you cannot find something on the website or just want an expert opinion on something about brands of boat propellers for sale on the site call us at 1-800-573-5533 and we will help any way we can.
Stern Lifting Propellers and Bow Lifting Propellers
Stern Lifting Propellers or Bow Lifting Propellers?
What type of boat propeller would work best for your boat? It depends on a few things. Type of boat is one and how you want to use it is another. For high powered light bass boats you want the most speed you can get ,that means a three blade prop with a higher rake degree. This type creates the most speed. Three bladed boat propellers with a high degree of rake are generally faster than a four bladed propeller. Four bladed propellers actually give better stern lift and less bow lift even if it has a high rake degree simply because the extra blade. If you have a sterndrive family style boat, a stern lifting prop is most popular because sterdrive boats are stern heavy and need help getting up and on top of the water quicker.
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