%PDF-1.7 A deep Vee hull will result in a different measurement than a flatter . <> Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features. All rights reserved. Trimming in, trimming down, and trimming out are all terms that a beginning boater should learn. Basically, there are three main ways to measure motor Or measure from the main engine prop up to the water line? Here is a picture that shows you exactly where the outboard motor shaft length stands: Usually the shaft length for outboard motors falls into the following 4 sizes: In practice, you may find the outboard motor shaft length varies among different brands and manufacturers like the Honda,Suzuki, Yamaha, Torqeedo, etc. If measuring an existing outboard: Measure from the inside top of mounting bracket down to anti-cavitation plate above propeller (this is the largest plate/fin directly above the propeller). Now that you have a better understanding of boat transom heights its time to take out the ruler and get the perfect measurements. As summer approaches there will be more boaters taking to the water. A long shaft engine requires a height of 20 and extra-long shaft engines will need a transom height of 25. This could also effect your travelling capabilities on the boat trailer. So in hopes that this will help out some new boaters this spring, here's a little rundown on outboard shaft sizes and how to figure out which one you actually need. 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. Attention: Remember to measure the outboard shaft length straight up and down instead of measuring along the transom. jackplate to a point level with the top of the transom. As with anything, there are exceptions to the rule. As a yacht designer and boater, I prefer longer shafts. Depending on the manufacturer, size names might change. As mentioned above, the operation of the propeller relies on the transom height. This also means it can affect the safety of the boat. function gtag(){dataLayer.push(arguments);} His works have appeared in regional newspapers in North Dakota and in "North Dakota Horizons" and "Cowboys and Indians" magazines. A long shaft engine requires a height of 20 and extra-long shaft engines will need a transom height of 25. Whether you already own a boat or looking for your first watercraft we are here to service your needs. I also love helping others, which is why I created this website. If it measures anywhere from 17" to around 22", then your going to want to go with a long shaft motor. Trimming in, trimming down, and trimming out are all terms that a beginning boater should learn. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. This was the height of my 225 Yamaha on my TR21 This website uses cookies to improve your experience while you navigate through the website. For over five years he has worked as a newspaper reporter and historic researcher. This cookie is set by GDPR Cookie Consent plugin. s.setAttribute("href", "https://cdn.paytomorrow.com/css/pt-mpe.min.css"); This cookie is set by GDPR Cookie Consent plugin. While this is the case there is certain saltwater motors that are extra extra long at 30 and 35 shaft. 4 0 obj The transom angle is the vertical incline of the transom and is measured in degrees. Here we look at the effects of standard, lower and higher mounting. Thats a fairly simple list of symptoms, but if your motor is too low, youll probably notice at least one of them. Safely but briskly accelerate. Doing so, will put the propeller right below the boat. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc. This will be the These are vertically aligned so the boater can make adjustments. Save my name, email, and website in this browser for the next time I comment. The motor length corresponds to the transom height of the boat, measured from the keel to gunwale at the transom. Get the latest updates on new products and upcoming sales, 2023 Marine Parts Warehouse Incorporated To make the yard stick long enough to measure the length of all the clubs, tape the ruler to the top. The transom is the boats flat vertical part at the back. Then open up the clamp bucket. The first step is to determine the height of your boat's transom. An inch or two probably wont make a big difference, but any more than that will lead to trouble. Although the longer outboard shaft length can lead to lower speed and more drag, the boat can push a heavier load. Re: Dinghy with a long shaft motor? For example, you can have the Mercury outboard shaft length by model code. The flat part of the bracket that rests on the transom when mounted will give you the same point of reference as the transom does on the boat. 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. This is measured by the propeller shaft being parallel to the vessels bottom. Safely but briskly accelerate. Determining Your Boat Transom Angle The transom angle - commonly measured in degrees - is the transom's vertical inclination. Theyre also useful if the back of your boat has a non-standard measurement. With such an important, long-term, and expensive upgrade, its never a bad idea to double-check. | Sitemap, The Marine Parts Warehouse Outboard Museum, OBR Powerhead / Shortblock Warranty Claim Form, Remanufactured vs. 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. Outboard Motor Shaft Length: How do I measure? As with anything, there are exceptions to the rule. The cavitation plate is the horizontal surface of the lower unit immediately above the propeller. When the jet drive is on the motor, set the height so that the leading edge of the intake is flush with the boat bottom. ), and place it on the bottom of the pad in the center. Take the center measurement from the top to the bottom of the hull. This will keep the prop in the water when the boat pitches in waves, or hobby-horses. Plus, a low transom cut is an invitation for the water to flood the boat. 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. I hope this helps someone out in their search for a new or newer outboard this season. displayPrimeOffers: true, bracket. If you are looking to repower, they may be able to offer some sage advice. The brackets can add 1 inch to the overall mounting height of the outboard. You need JavaScript enabled to view it. (We wont go into name-calling here, but the actual term for the cavitation plate is an anti-ventilation plate.) Variables to consider when determining the mounting height include the size and style of the boat and the length of the outboard motor's shaft. What is the Virtual Sundance Film Festival? These allow the mounting of a standard length outboard behind the transom. All you need to do is measure how much to rise. var prefix = 'ma' + 'il' + 'to'; the aluminum plate on top of the transom), to the bottom of the motor Some may call it a standard length while others may call it a short or a long shaft. 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. (function (d) { Some boats are equipped with transom-hung outboards while others have a bracket. This cookie is set by GDPR Cookie Consent plugin. It also cuts into speed and fuel efficiency. The transom is the back of the boat where the motor is hung. If youd like to see this in video format, skip to 0:44 in the below YouTube Video: Is it OK to put a long shaft outboard on a boat thats rated for a short shaft? So how to determine the outboard shaft length? To do so, take a measurement from the very top to the very bottom of the transom in the precise center. It is possible that the motor could hang low while transporting on the boat trailer causing future boat repairs. However, the motor should not be raised more than 5 inches above the standard position. This measurement would be the inches of Ill also explain the difference between short and long shafts and how they vary by type of boat. Follow Westshore Marine & Leisure on Twitter! Any owner seeking the last bit of speed from an outboard-powered boat should grab a yard stick. #2. If the propeller fails to ventilate, the motor is mounted to low. All things considered, sticking with the industry standard is best for the beginner. 1855 Alpine Avenue NWGrand Rapids, MI 49504This email address is being protected from spambots. loadScript(ptScript); var ptScript = "https://cdn.paytomorrow.com/js/pt-mpe.min.js"; https://www.bornagainboating.com/Get Your Born Again Boating Clothing! This measurement is primarily designed for single motor propulsion. since 1986. I run a 9.9 Mercury Bigfoot 20" shaft off the swim platform of my 89 Trophy 2160. So if you are measuring the outboard shaft length for smaller boats, inflatables, dinghies, sailboat or other low-speed work boats, the cavitation plate is often about 2 below the bottom. It is very versatile as it generally . #1: Height Will Charpentier is a writer who specializes in boating and maritime subjects. There are instances where a lower mount may be okay. Figuring out how to measure motor height on a would be more accurate.) It does not store any personal data. The how to measure the shaft length of an outboard motor is a question that many people have asked. displayMicroOffers: false, }, 100); Setting Height of Outboard Motor - YouTube 0:00 / 0:46 Setting Height of Outboard Motor nates90 71 subscribers Subscribe 83 Share 63K views 7 years ago #boatservice #outboardmotor. your motor will be higher.) 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. The outboard comes with mounting holes and brackets. The distance between the ends of a transom is measured in inches. This, however, is not recommended for the beginning boater. The pros and cons of properly . The transom is the rear wall of the boat where the outboard engine is mounted in the middle. It also cuts into speed and fuel efficiency. window.dataLayer = window.dataLayer || []; You will also risk hitting bottom or submerge objects more frequently such as rocks or logs. Outboard motors can be fitted to a variety of boats, so manufacturers have standardized their engines to go on virtually anything. https:/. If you have a small boat with a 15 to 17 inch aft transom, youll most likely need a short shaft outboard. 7. It doesnt matter if you have a fiberglass boat, bay boat, big or small boat. All things considered, sticking with the industry standard is best for the beginner. According to MarinePartsMan.com, the outboard can be raised 1 inch above the standard height for every 10 miles per hour of speed the boat can attain. Another important measurement is the transom angle. maxTerm: 36, 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. var interval = setInterval(function () { Measuring the shaft length can be done in various ways, but the most common way is by using a tape measure. 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. The correct shaft length for your boat depends on a few factors. 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. Boat Transom Heights The Beginners Guide, Buying a boat can be an exciting purchase.