If you are running a slower boat, the exact location of the ventilation plate is less important. Increased RPM and additional horsepower feed the need for speed. You also have the option to opt-out of these cookies. Sailboats use these sometimes, as well as some boaters who want to install a much smaller auxiliary motor to use in case of primary engine failure. Your at your local outboard dealer shopping for a new motor and the salesman hits you with the question, "short or long shaft?". These are vertically aligned so the boater can make adjustments. This transom saver will support the weight of your outboard throughout your road travel, steadily bracing it against the trailer frame to relieve your transom of the weight and impact from consistent bouncing. All rights reserved. %PDF-1.7 Step 2 requires the propeller's radius (check the user manual and then the technical drawing). Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors. On the downside, a higher mount can interfere with the boaters steering capabilities. Mounting the outboard a little bit lower than the standard point could avoid the possible ventilation and slip on acceleration. Propshaft in Its important to note that manufacturers call their models different things. This alone can outweigh the negatives when deciding to adjust the mount upwards. Safely but briskly accelerate. 2019s List of the Best Recreational Pontoon Boats for Sale. var h = d.getElementsByTagName("head"), However, you will need an understanding of how the degrees will alter the boats usability. Smaller inflatables and dinghies needshort shaft motors, whilst bigger boats require long or, in some circumstances, extreme long shaft versions. These cookies ensure basic functionalities and security features of the website, anonymously. trimming the motor out by one-half to full trim. Keep these numbers in mind if you ever have a need for a new outboard motor for your boat. However, the motor should not be raised more than 5 inches above the standard position. For slower boats, its less critical to. var interval = setInterval(function () { Mounting the outboard motor in accordance with the industry standards is important. The shaft length for outboard motors has nothing to do with the water line. If your boat is newer and the manufacturer is still in business, you might also want to try to give them a call. If you went too long it would still work but it may lack in performance. h[0].appendChild(s); Displacement hulled vessels like sailboats and workboats can benefit from a little more space between the hull and cavitation plate, but not much. since 1986. Boost Speed with Outboard Engine Height Adjustments Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet. A2: Instead of changing to the short outboard shaft, you can try the Jack Plate first. Your email address will not be published. And thats usually the case since the electric outboards are designed with larger and more efficient propeller that needs longer shaft. Read the following to get the optimal shaft length for outboard motors! To break it down a bit more for you: Short shafts are 15-inches long. Now that you have a better understanding of boat transom heights its time to take out the ruler and get the perfect measurements. var path = 'hr' + 'ef' + '='; It is very versatile as it generally . resting on the transom if you had the motor all the way down on the boat The height of the boat transom dictates the size of the outboard motor. The transom angle is the vertical incline of the transom and is measured in degrees. If you have already measured you transom tip to bottom to be 20", then if you place aux sdieways to central engine your available transom height will be probably 1"-1.5" " higher and work perfecty. Its where the outboard motor is attached, and its also where some boat owners put the boats name. There are also specialty motor shaft lengths. the aluminum plate on top of the transom), to the bottom of the motor If you said you have a pontoon or a larger style boat such as a bass boat or speed boat, I would be pretty confident in saying it needs a long shaft. Eq*^?6R83e+j}UY.(M7k]~4g)g ~wmS{ O7t/o(W|X? Mounting kicker motor - General Discussion Forum | In-Depth Outdoors The outboard comes with mounting holes and brackets. How to Find Your Shaft Length | ePropulsion The pros and cons of properly . Boaters who consider going with a higher mount can see increased speeds. ensure that your measurement is accurate. All things considered, sticking with the industry standard is best for the beginner. However, your boat will have slightly more drag which will reduce your maximum speed. Top 10 Choices for Boaters, Mercury Introduces 600HP V12 Verado Outboard Engine, The Outboard Expert: Tohatsu Propane Outboard Engine. Save my name, email, and website in this browser for the next time I comment. var addy_textd53b59933f6c3f2e8b59f1b4a6d41fa5 = 'info' + '@' + 'vanssports' + '.' + 'com';document.getElementById('cloakd53b59933f6c3f2e8b59f1b4a6d41fa5').innerHTML += ''+addy_textd53b59933f6c3f2e8b59f1b4a6d41fa5+'<\/a>'; The cookie is used to store the user consent for the cookies in the category "Performance". This is somewhat similar to #2, in that you are again measuring with a So from there, I will try to help out by asking questions about your boat such as what type it is and the length. If you are looking to repower, they may be able to offer some sage advice. This is handy if youre shopping for second-hand outboards or looking to sell the one that came with your boat. The engine may be lifted one inch for every eight to ten inches of distance between the transom and the prop, according to a boat riggers rule of thumb. Picking the right shaft length for your outboard is an essential step in getting the best performance from your boat. It moves an outboard up and down to optimize performance and enable a boat to venture into shallower water than it might otherwise. Trimming in, trimming down, and trimming out are all terms that a beginning boater should learn. var prefix = 'ma' + 'il' + 'to'; Learn More About Your Boats Systems By Joining The Born Again Boating Academy! Motor height on pontoon? | Boating Forum - iboats Boating Forums You need JavaScript enabled to view it. Engine Oil Mixing Ratio Fuel 50: Engine Oil 1. This is measured by the propeller shaft being parallel to the vessels bottom. This is probably the worst case scenario out of the two. e-mail boats.com, 1221 Brickell Avenue, 23rd Floor, Miami, FL 33131, USA. boats.com is part of the Boats Group Network. You need JavaScript enabled to view it. While this is the case there is certain saltwater motors that are extra extra long at 30 and 35 shaft. 2 0 obj How do you measure a transom on an outboard motor? will be to the flat part; if you measure to the bottom of the brackets A deep Vee hull will result in a different measurement than a flatter . The outboard shaft length is the vertical distance between the top of the mounting clamp bracket and the bottom of the cavitation plate (aka the ventilation plate). It varies between different motors and boats. Other boats that need long shafts are. manufacturer will recommend the outboard height according to the bracket shape and length. a Detwiler manual jackplate. up to the bottom of the motor brackets, (as in #1). Once you know what will fit on your hull, you can fine-tune your choice based on the performance youre looking for and how you use the boat. Keith Allen, a 1979 graduate of Valley City State College, has worked at a variety of jobs including computer operator, medical clinic manager, radio talk show host and potato sorter. ), and place it on the bottom of the pad in the center. not sure that it's still used. 7. Buying a boat can be an exciting purchase. The average transom angle is around 14 degrees. This, however, is not recommended for the beginning boater. A retired ship captain, Charpentier holds a doctorate in applied ocean science and engineering. maxAmount: 6500.0, (We wont go into name-calling here, but the actual term for the cavitation plate is an anti-ventilation plate.) storeDisplayName: "Marine Parts Warehouse", primeApr: 12.99, function loadScript(script) { As a dealer I don't really like hearing this because there is a chance it could go either way and you have to get it right. })(); This is also known as the shaft length. As mentioned above, the operation of the propeller relies on the transom height. This could also affect your travelling capabilities on the boat trailer. Or it can have an angle degree as high as 30. One of the great things about an outboard motor is how versatile it is. The mounting height of the outboard engine is the equivalent of the distance between the base of the motor and the top of the propeller. To achieve this, the motor itself has to be attached at the correct height. Engine Oil Type Genuine or Recommended 2str Engine Oil. xmlHttp.setRequestHeader('Content-Type', 'application/json'); In lower mounting, the engine is set lower than the recommended standard. When it gets to the short side (14), When the inner corner of the square comes into touch with the transom, measure the distance between the inside corner of the square and the boat bottom (see drawing below). The average transom angle is around 14 degrees. The height of the transom is calculated by measuring from the bottom of the hull to the top of the transom, using the center line. maxMicroAmount: 0.0, But in many cases, its a little more complicated than that alone. Boats with extended transoms, brackets that extend the mounting bracket for the outboard motor behind the back of the boat, can use a higher outboard height. Measuring the shaft length can be done in various ways, but the most common way is by using a tape measure. Some fishing boats can handle the motor being underwater. Other boats that need short shafts are: A: If you have a small boat with a 18 to 21 inch aft transom, youll most likely need a long shaft outboard. What Is Boat Transom Height? | Gone Outdoors | Your Adventure Awaits How to Choose Between a Motor Tote and Transom Saver to Support an Add yours in the comment and Ill get back to you asap. There loadScript(ptScript); Then adjust the motor in a higher hole with a flat head screwdriver. Raising the motor increases the speed of the boat while decreasing the effort needed to turn the boat. The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional". |. If you have a short shaft motor, the distance between the top of the transom and the bottom of the boat should be between 15 and 16 inches. Doing this can have adverse effects. The transom is the back of the boat where the motor is hung. on How to Measure Outboard Shaft Length: The Only Guide You Need, ePropulsion vs Torqeedo: An All-Round Comparison, 55 lb Thrust Trolling Motors: All You Need to Know Before Purchase, Spot Lock Trolling Motor: Is It Worth It & Best Options in 2022, Wiring 24V Trolling Motors: 24 Volt Wiring Diagram (with Video), LiFePO4 Battery: Why Lithium iron Phosphate Batteries Are Your Best Options in 2022, Minn Kota vs MotorGuide: Best Option in 2022. At least if its too long you can raise the motor or "build up" your transom. To measure the transom height, measure from the center on for transom (rear of the boat). }, 100); The correct shaft length for your boat depends on a few factors. The greater the number, the more the drive may sway (also called tuck under or negative trim). To measure your outboard motor shaft length, measure from the bottom of the mounting bracket where it rests on the transom to the top of the cavitation plate, this is the horizontal surface of the lower unit immediately above the propeller. } However, you will need an understanding of how the degrees will alter the boats usability. The cookie is used to store the user consent for the cookies in the category "Analytics". your motor will be higher.) Simply start with the engine in idle, followed by trimming the motor out by one-half to full trim. from the transom. You'll need a short shaft outboard if it's 15 or less than an inch shorter. How to Measure Shaft Length on Outboard Motor? - TrollinMotorsGuide Beginning boaters should be aware of the boats measurements. Yes, if there is adequate space while the engine is tilted in the up position, a larger shaft length than what is specified may be used. Mounting the outboard motor in accordance with the industry standards is important. The height of the transom is estimated by using the center line to measure from the bottom of the hull to the top of the transom. Generally, the anti-ventilation plate on most engines is aligned with the bottom of the vessel. <>/ExtGState<>/XObject<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 595.2 841.8] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> Check the literature about your model boat online, and you may be surprised to find that the number is published for you. Yamaha Outboard Motors: How To Measure Leg Length An inch or two probably wont make a big difference, but any more than that will lead to trouble. Here we will guide you in how to get the right boat transom height. Make sure that you are measuring straight up, at a 90 degree angle to Outboard shaft length plays a crucial role in the performance of your boat. This would not be a good thing. Cavitation is when the propeller is out of the water due to the boat forming a wake of "air bubbles" or "vapor cavities" around the prop. addyd53b59933f6c3f2e8b59f1b4a6d41fa5 = addyd53b59933f6c3f2e8b59f1b4a6d41fa5 + 'vanssports' + '.' + 'com'; A long shaft engine requires a height of 20 and extra-long shaft engines will need a transom height of 25. enableMoreInfoLink: true, Long shafts are 20-inches long. You run the risk of possibly unsafe handling if you attempt to put a long shaft engine on a transom designed for a short shaft engine. Industry transom height standards have been evolved during the last 30 years: 15 for short shaft engines, 20 for long shaft engines, and 25 for extra-long shaft engines. The cookie is used to store the user consent for the cookies in the category "Other. You must be still in the blue about that matter. Use the mounting bracket on the motor to know where it will sit on the boat. Because of the increased friction, cavitation reduces efficiency. Measure the area of the transom directly where the engine will be mounted. <>/Metadata 127 0 R/ViewerPreferences 128 0 R>> Industry standards dictate that for short shaft engines the transom height should be 15. How to Measure Transom Height For vessels with transom-mounted outboards, you can easily figure out which type of outboard you need to get. Gear case sits just below or at the hull depth due to the deep v. The performance of these boats depends on quite a lot of factors, but getting the outboard length just right is an essential first step. It is extremely important that the boater understands the significance of the transoms height. It is possible that the motor could hang low while transporting on the boat trailer causing future boat repairs. Hold the tape on the top, center of the taffrail and measure straight down to the point, usually a sharp angle, where the transom joins the bottom of the boat. Check out the Westshore Marine & Leisure Youtube page! So how to determine the outboard shaft length? Why Rebounding Is A Key Skill for Fouth Players To Learn, Tips For Attacking a Zone Defense as a Youth Basketball Team, Why This is a Big Deal for the Sports Betting Industry. There are 2 steps to help get a relatively accurate figure. 1855 Alpine Avenue NWGrand Rapids, MI 49504This email address is being protected from spambots. Ten years ago I bought my first boat. Most transom savers can support up to a 150HP motor, which is sufficient for most regular boats. These two measurements will give you the length of the shaft you need. *The Factors indicates the adjustment affected by on your boat type, the outboard working environment, and the transom distance as discussed above. Place the bracket on the transom to the left of the main outboard or rudder. The boat transom height is measured from the lowest point on the keel along the center line to the spot where the outboard motor's mounting holes bracket rests. The anti-cavitation plate above the prop needs to be within an inch of the bottom of the transom, therefore, the prop should be well below the transom. document.getElementById('cloakd53b59933f6c3f2e8b59f1b4a6d41fa5').innerHTML = ''; The propellers will also have trouble reaching the water. Upstream Securitys Disruptive Telematics Technology, The challenges of scaling a cloud-based security system, OneStreams unified platform streamlines financial data management, OneStreams impact on the financial software market. Plus, a low transom cut is an invitation for the water to flood the boat. How Low Should a Motor Set on a Pontoon Boat? (Explained) No matter what size of boat you are running, one of the most critical choices you can make when buying an outboard motor is the shaft length. var BCData = {"csrf_token":"d7ecb6b56891bb66aee12dbc01a80162b3ed582c1acbe30f16fc9f1b2abc362f"}; This is a measurement that has been used for BassCats, I'm Tilt your motor until the bullet of the gearcase is Higher mounting decisions should be left to the professionals. However, youll notice a little increase in drag and a decrease in top-end performance. Beginning boaters should be aware of the boats measurements. :$I>M W$h"%U_yzIb?]NHg_G|r@nX eTf."SQ It also includes attaching the right engine. Most of the time, adding a hydrofoil to an outboard improves performance. These are vertically aligned so the boater can make adjustments. Knowing the width, height and depth of your transom allows you to make several important decisions when selecting or purchasing a new outboard. A big NO. This alone can outweigh the negatives when deciding to adjust the mount upwards. Basically, there are three main ways to measure motor height (that I'm aware of); probably the most common is: # 1: Height of the motor off the transom This is simply a measurement taken from the top of the transom (top of the aluminum plate on top of the transom), to the bottom of the motor "brackets". Outboard Motor Shaft Length: How do I measure? The vertical distance between the interior of the clamp and the cavitation plate is the shaft length specified by the outboard manufacturer. If it measures 15" or with in a inch of that you will need a short shaft outboard. A: Any boat that has a 21 to 27 inch aft transom will need an extra long shaft outboard. Beefier jack plates can be fitted should a boater be looking to mount an outboard with a shorter shaft than their transom demands. bracket forward with a straight edge to where you can then measure up And the rule of thumb is that you should keep the cavitation plate level with the bottom or keel of the boat. If you have a question or need additional information. Will Charpentier is a writer who specializes in boating and maritime subjects. Copyright 2017 Dealer Spike All Rights Reserved. It was a 23-foot Crestliner Grand Cayman pontoon boat. Transom Outboard Engine Position - YouTube How Transom Height Is Measured C Cheaptoon Cadet Joined Aug 4, 2010 Messages 28 Aug 24, 2010 #4 Re: Motor height on pontoon? Raising an outboard higher on the transom can reduce drag and raise top speed. Other factors to consider when determining the mounting height of an outboard are related to performance.