#3. So you should just measure the height of the boat's transom from the center down to the lowest point of the hull, and compare transom height with the outboard shaft length numbers. 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. An inch or two probably wont make a big difference, but any more than that will lead to trouble. Commonly, the transom angle ranges from 0-30 degrees, with the average transom angle set at 14 degrees. Measure straight down to the lowest point on the hull. You can order an outboard in lengths ranging from 15 inches to 30 inches, depending on its power output and possible uses. Selecting the Correct Size Outboard Shaft, What is the Best Outboard Motor for Saltwater, Diagnosing Common Outboard Motor Problems, Best Beginner Boats Everything You Need to Know. These cookies will be stored in your browser only with your consent. https://www.bornagainboating.com/Get Your Born Again Boating Clothing! If you said something smaller than that, thats where it can get tricky. Which Navigation Lights Does Your Boat Need? The rearmost structural member of your boat, it not only distributes the stress of the hull generated by the bow's impact as it cleaves the water, it's the place you hang your outboard motor. Anything bigger than that your obviously going to need an extra long shaft. Here we will guide you in how to get the right boat transom height. Small portable outboards ranging from 2 to 20 horsepower are usually sold only in short or long shaft versions. Add yours in the comment and Ill get back to you asap. xmlHttp.open('POST', 'https://bes.gcp.data.bigcommerce.com/nobot'); This is handy if youre shopping for second-hand outboards or looking to sell the one that came with your boat. storeDisplayName: "Marine Parts Warehouse", Again, make sure that you are measuring to the flat part of the brackets; Take a long straight edge, (long carpenter's level or long var xmlHttp = new XMLHttpRequest(); If so, send me an There is a simple test to see if your outboard motor is set at the best height. Say the 20 shaft is a long shaft length for gas engines, but it is a short shaft length for electric outboard motors. 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. Finding the right size is a matter of looking at what youve got and taking out the measuring tape. Because of the increased friction, cavitation reduces efficiency. As a yacht designer and boater, I prefer longer shafts. The lowest point will likely be directly under your drain plug if youve got one. He is a (Any measurement given as "off the transom" Smaller 12-14 foot boats can require either a short or long shaft outboard depending on the style of the boat and the brand. You also might not be able to lift the outboard out of the water entirely for storage. As with anything, there are exceptions to the rule. Long shafts are 20-inches long. The transom is the flat vertical section at the rear of the boat. }, 100); In lower mounting, the engine is set lower than the recommended standard. mpeInit(); 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. When mounting the engine, you want the cavitation plate to be 1 above the boat bottom for every 12 away from the transom. If you have a small boat with a 15 to 17 inch aft transom, youll most likely need a short shaft outboard. 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. Is my outboard long or short shaft? This measurement is primarily designed for single motor propulsion. If you are running a twin-engine setup, then measure the same distance from each clamping plate to the bottom of the hull. 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. A1: Broadly speaking, the outboard motor shaft length for pontoon boat, bass boat, or other larger boats should be long shaft. The outboard comes with mounting holes and brackets. How to Measure Transom Height For vessels with transom-mounted outboards, you can easily figure out which type of outboard you need to get. % The transom is the flat vertical section at the rear of the boat. These are vertically aligned so the boater can make adjustments. Picking the right shaft length is mostly a factor of the transom height or the back of the boat. 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. boats.com, 1221 Brickell Avenue, 23rd Floor, Miami, FL 33131, USA. If possible for your peace of mind and not let down that magnificent purchase opportunity, place that 08 kicker at back transom and test for yourself. Before we get started lets see what a boat transom is and what it does. Raising the motor increases the speed of the boat while decreasing the effort needed to turn the boat. Having the cavitation plate too low will cause excess drag and reduced performance at high speeds. Some fishing boats can handle the motor being underwater. You need JavaScript enabled to view it. 7. They operate as a planing surface, allowing your boat to climb to the top more quickly. from the transom. The height of the boat transom dictates the size of the outboard motor. You'll need a short shaft outboard if it's 15 or less than an inch shorter. Learn More About Your Boats Systems By Joining The Born Again Boating Academy! of the "bullet" on your lower unit. All you need to do is measure how much to rise. A retired ship captain, Charpentier holds a doctorate in applied ocean science and engineering. How Transom Height Is Measured The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional". Your goal is to measure how the outboard will sit, so start from the clamping plate and follow the centerline of the hull. On this type of boat, if you are in doubt, default to the longer-shafted outboard. 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. His works have appeared in regional newspapers in North Dakota and in "North Dakota Horizons" and "Cowboys and Indians" magazines. And thats usually the case since the electric outboards are designed with larger and more efficient propeller that needs longer shaft. Attention: Remember to measure the outboard shaft length straight up and down instead of measuring along the transom. Boaters who consider going with a higher mount can see increased speeds. Place the rulers end on the ground behind the club and let the club to rest on top of it. The cookie is used to store the user consent for the cookies in the category "Analytics". 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 motor length corresponds to the transom height of the boat, measured from the keel to gunwale at the transom. It is extremely important that the boater understands the significance of the transom's height. Check out the Westshore Marine & Leisure Youtube page! Whats the best height for my boat motor? The standard shaft length for most outboard engines less than 125 horsepower is 20 inches. Boaters who consider going with a higher mount can see increased speeds. Oftentimes you will want to adjust the outboard shaft length in order to improve the boat performance such as speed. Assistant Measuring tape Grease pencil Ask a friend to hold one end of a measuring tape at the extreme outer edge of the top of the transom while you pull the tape across its width to the opposite outer edge to measure the "length of the taffrail," which is the width of the boat across the top edge of the stern. Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet. All boats are different, and the motor manufacturers produce a variety of standard lengths. Actual shaft length is 21.5" on those. It doesnt matter if you have a fiberglass boat, bay boat, big or small boat. Any owner seeking the last bit of speed from an outboard-powered boat should grab a yard stick. The greater the number, the more the drive may sway (also called tuck under or negative trim). trimming the motor out by one-half to full trim. It doesnt matter if you have a fiberglass boat, bay boat, big or small boat. Keep these numbers in mind if you ever have a need for a new outboard motor for your boat. Boats with more engine power and weight require longer shaft outboards for better balance. <> To do so, you will want to measure at the exact center of the transom from the very top to the very bottom. Since the length of the shaft of your outboard is associated with the size boat, smaller engines will generally have shorter shafts. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc. Add the two measurements and you get 6 1/2". And the rule of thumb is that you should keep the cavitation plate level with the bottom or keel of the boat. With more than a decade of experience cruising the lakes in my Crestliner Grand Cayman pontoon boat and my Boston Whaler, I now want to share everything I've learned with my community here at Boating Hub. bracket. With a jack plate, you can mount it exactly where you want it. measuring; you may have to "extend" the flat part of the var h = d.getElementsByTagName("head"), stream To do so, you will want to measure at the exact center of the transom from the very top to the very bottom. What Kind of Fuel Does Your Marine Engine Need? Rest the yard stick or another suitable straight edge along the keel on the bottom of the boat so that it makes a straight line aft to the outboard. Engine Oil Type Genuine or Recommended 2str Engine Oil. This alone can outweigh the negatives when deciding to adjust the mount upwards. I would ask you to go back and measure the transom of your boat. Check out the full chart of the Mercury outboard model code and its features. On the downside, a higher mount can interfere with the boaters steering capabilities. The shaft length for outboard motors has nothing to do with the water line. to where the brackets were actually resting on the transom. minAmount: 300.0, These cookies track visitors across websites and collect information to provide customized ads. Check out the Westshore Marine & Leisure google plus page! %PDF-1.7 The propellers will also have trouble reaching the water. 3 0 obj You also have the option to opt-out of these cookies. bassboat can be a bit confusing at times; hopefully this will help sort The mounting height of an outboard motor can impact the speed and handling characteristics of the boat. In step 3, add another 10 cm (4") to the previous calculation in order to develop the ideal shaft length. (In the case of the faster 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. straight edge on the top of the transom to "extend" it out } Simply start with the engine in idle, followed bytrimming the motor out by one-half to full trim. To do so, take a measurement from the very top to the very bottom of the transom in the precise center. This cookie is set by GDPR Cookie Consent plugin. If you decide to make adjustments, please consult a marine engine dealer about the boat design. height (that I'm aware of); probably the most common is: However, the motor should not be raised more than 5 inches above the standard position. For most boaters this is a no brainer, but for the novice or inexperienced boater it may be a tougher question. priceSelector: ".price--withoutTax, span.price.price--withTax", There are instances where a lower mount may be okay. s.setAttribute("rel", "stylesheet"); Plus, a low transom cut is an invitation for the water to flood the boat. The first step is to determine the height of your boat's transom. |. Mounting the outboard motor in accordance with the industry standards is important. Other boats that need long shafts are. The pros and cons of properly . hulls, such as Allisons, Bullets, Strokers, etc., this measurement could The point where these measurements intersect is your centerline. This was the height of my 225 Yamaha on my TR21 maxTerm: 36, gtag('config', 'G-QX0Y76NH40'); Whether your on a pontoon boat, fishing boat, or speedboat boating is always one of the best times you can have. manufacturer will recommend the outboard height according to the bracket shape and length. If youre looking for a bracket that can handle motors of up to 10/15 horsepower, go no further. You reply, "Im not sure, I think its a long". Beginning boaters should be aware of the boats measurements. To make the yard stick long enough to measure the length of all the clubs, tape the ruler to the top. This is the dimension you'll need to know when deciding between a short shaft, long shaft or extra long shaft for your outboard motor. AztH ^zv_ cT,E1K/rAB54| displayPrimeOffers: true, Smaller inflatables and dinghies needshort shaft motors, whilst bigger boats require long or, in some circumstances, extreme long shaft versions. Since the ventilation plate & foil are burried under water it is obviously too low. Engine Oil Mixing Ratio Fuel 50: Engine Oil 1. The form of a boats transom varies depending on the manufacturer and model. This number will likely be shorter than that for a single-engine installation since you do not necessarily measure to the point of the keel. 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. Should I take the raft onto the water and measure the exact distance from the top of the transom to the water line? If the propeller fails to ventilate, the motor is mounted to low. 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. It is possible that the motor could hang low while transporting on the boat trailer causing future boat repairs. Mounting the outboard motor in accordance with the industry standards is important. Expectedly, when the transom angle is zero, it means it is flat. 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.

Charlotte Tilbury Exagger Eyes Liner Duo Dupe, Articles H