how to measure transom height for outboard motor

Take a long straight edge, (long carpenter's level or long All rights reserved. 1 0 obj Eq*^?6R83e+j}UY.(M7k]~4g)g ~wmS{ O7t/o(W|X? Among them will be first-timers or those who have recently purchased their boats. https:/. endobj With a motor tote, the outboard and boat move as one, independently of the trailer, so there are no concerns about the boat shifting on the trailer, he says. Step 2 requires the propeller's radius (check the user manual and then the technical drawing). There are instances where a lower mount may be okay. Cutting the transom down is the only legal method to utilize a short shaft engine on a tall transom. These are vertically aligned so the boater can make adjustments. Transom Outboard Engine Position - YouTube 0:00 / 0:56 Transom Outboard Engine Position BOATING SCENE 763 subscribers 609 211K views 5 years ago www.boatingscene.com.au Sometimes when your. In lower mounting, the engine is set lower than the recommended standard. With it comes a lot of responsibility and new things to learn including, Why your boat transom needs to be the right height, The pros and cons of properly mounting the outboard motor to the transom, Standard mounting is always best for the beginner, Of course, its always best to go with standard practices when choosing the, Lower mounting is not for the beginning boater, Mounting the motor lower on the boat transom, There is a simple test to see if your outboard motor is set at the best height. If the propeller fails to ventilate, the motor is mounted to low. Mounting the outboard motor in accordance with the industry standards is important. your motor will be higher.) The boat transom can be flat with zero degree angles. bassboat can be a bit confusing at times; hopefully this will help sort 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. I hope this helps someone out in their search for a new or newer outboard this season. LOYALHEARTDY Outboard Motor 6 HP 2-Stroke Inflatable Fishing Boat Some may call it a standard length while others may call it a short or a long shaft. No one wants to have issues with a new transom or boat repairs. These cookies ensure basic functionalities and security features of the website, anonymously. manufacturer will recommend the outboard height according to the bracket shape and length. help with shaft length for a kicker - iboats Boating Forums It can also improve the experience of driving a faster boat. If you have a fast boat, getting the outboards cavitation plate at the same level of the hull will ensure quick hole shot and fast top-end speeds. The current measurement is the ventilation plate is about 1 1/2" above the true keel line which is about 24" in front of the motor edge. The cookies is used to store the user consent for the cookies in the category "Necessary". If so, send me an C Cheaptoon Cadet Joined Aug 4, 2010 Messages 28 Aug 24, 2010 #4 Re: Motor height on pontoon? What matters is the actual measurement in the specifications, not the name. (We wont go into name-calling here, but the actual term for the cavitation plate is an anti-ventilation plate.) Wherever the outboard clamping bracket is, use this as the basis for measurement. This exhaust port should be about 1 inch above the water line when the boat is idling. Now that you have a better understanding of boat transom heights its time to take out the ruler and get the perfect measurements. How Transom Height Is Measured % } function loadScript(script) { (3) Move horizontally across the chart until you hit the graph curve. Usually speaking, the farther the outboard is set off the transom, the higher the propeller should be in the water (or the higher the outboard can be mounted). One of the great things about an outboard motor is how versatile it is. Smaller 12-14 foot boats can require either a short or long shaft outboard depending on the style of the boat and the brand. s = d.createElement("script"); The first order of business is to measure your boat for the ideal fit. Mounting kicker motor - General Discussion Forum | In-Depth Outdoors However, the motor should not be raised more than 5 inches above the standard position. When measuring the transom height, you should start from the hull's bottom at the boat's center line up to the top of the transom. August 9/08). If you decide to make adjustments, please consult a marine engine dealer about the boat design. Make sure that you are measuring straight up, at a 90 degree angle to Actually there is no designated letter for short shaft. Knowing the width, height and depth of your transom allows you to make several important decisions when selecting or purchasing a new outboard. What Types of Documents Can be Sent to your Kindle Library? maxAmount: 6500.0, Doing this can have adverse effects. Measuring Motor Height - BassBoat Central Smaller inflatables and dinghies needshort shaft motors, whilst bigger boats require long or, in some circumstances, extreme long shaft versions. The same is true for the newest, high-powered offshore fishing boats, where triple or quadruple motor setups are becoming more and more common. However, you will need an understanding of how the degrees will alter the boats usability. Mounting the motor lower on the boat transom can create excessive spray, increase case drag, reduce underwater clearance, and negatively impact faster boats. })(); Trimming in, trimming down, and trimming out are all terms that a beginning boater should learn. A deep Vee hull will result in a different measurement than a flatter . 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. Add the two measurements and you get 6 1/2". This placement is not only recommended but it will give you the best performance compared to something that is too long or too short. What Kind of Fuel Does Your Marine Engine Need? The amount of degrees the transom leans back from vertical is known as the transom angle. MPW eBay Store - Thousands of New OEM Old Stock Parts! You 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. While this is the case there is certain saltwater motors that are extra extra long at 30 and 35 shaft. If you went too long it would still work but it may lack in performance. You reply, "Im not sure, I think its a long". One of the main concerns is causing the engine to overheat if not enough water reaches the engine to keep it cool. With it comes a lot of responsibility and new things to learn including boat maintenance and boat basics. Height Measurement: Recommended Shaft Length: 14" - 17.25" 15" Shaft (Short) 17.25" - 19.5" Varies by application 19.5" - 22.5" Look at the part of your motor that would be The transom is the rear wall of the boat where the outboard engine is mounted in the middle. Save my name, email, and website in this browser for the next time I comment. 7. Your email address will not be published. addyd53b59933f6c3f2e8b59f1b4a6d41fa5 = addyd53b59933f6c3f2e8b59f1b4a6d41fa5 + 'vanssports' + '.' + 'com'; (function (d) { AztH ^zv_ cT,E1K/rAB54| Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet. #2. the propshaft below or above the pad. This would not be a good thing. What's the best height for my boat motor? If you are running a twin-engine setup, then measure the same distance from each clamping plate to the bottom of the hull. It is possible that the motor could hang low while transporting on the boat trailer causing future boat repairs. Other boats that need long shafts are. If it measures anywhere from 17" to around 22", then your going to want to go with a long shaft motor. 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. 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. Ill also explain the difference between short and long shafts and how they vary by type of boat. Doing this can have adverse effects. 3 0 obj In the case of a larger offshore boat, it may be to the top of a cutout on the . Use the mounting bracket on the motor to know where it will sit on the boat. The outboard comes with mounting holes and brackets. Be sure to measure carefully and research thoroughly before diving in. 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. As summer approaches there will be more boaters taking to the water. Mounting the outboard motor in accordance with the industry standards is important. The standard installation of an outboard has the top of the transom of the boat at the same level as the bottom of the motor portion of the outboard. How Low Should a Motor Set on a Pontoon Boat? (Explained) bracket forward with a straight edge to where you can then measure up My family and I used it to fish, ski (yes, you can ski behind a pontoon boat), and cruise the lakes near our home. This is the dimension you'll need when selecting a width for your outboard motor's mounting bracket. The average transom angle is around 14 degrees. Some fishing boats can handle the motor being underwater. Before we get started lets see what a boat transom is and what it does. s.setAttribute("type", "text/javascript"); Cavitation plates are used on the bottom components of boats to help them operate better. If you go too short your more than likely going to cavitate and loose power. Or measure from the main engine prop up to the water line? PayTomorrow.mpeInit({ Depending on the manufacturer, size names might change. In the past, though, it housed the officers and captain of 17th, 18th and 19th century sailing ships. The greater the number, the more the drive may sway (also called tuck under or negative trim). These cookies track visitors across websites and collect information to provide customized ads. Most transom savers can support up to a 150HP motor, which is sufficient for most regular boats. He is a And the rule of thumb is that you should keep the cavitation plate level with the bottom or keel of the boat. They operate as a planing surface, allowing your boat to climb to the top more quickly. trimming the motor out by one-half to full trim. | Sitemap, The Marine Parts Warehouse Outboard Museum, OBR Powerhead / Shortblock Warranty Claim Form, Remanufactured vs. s.setAttribute("rel", "stylesheet"); Generally, short shaft outboards are 15 inches, long shaft outboards are 20 inches, and extra-long outboards are 25 inches. Typical motor lengths include the following. Re: Dinghy with a long shaft motor? Raising the motor increases the speed of the boat while decreasing the effort needed to turn the boat. Your goal is to measure how the outboard will sit, so start from the clamping plate and follow the centerline of the hull. Lastly, knowing the year of your motor and what style of controls you have (side mount, concealed side mount, or binnacle) is also a plus because it will tell the dealer if your current controls are compatible with the motor you are purchasing. He is also a certified marine technician and the author of a popular text on writing local history. Knowing how this can affect the overall operation of the boat is a factor to be considered. 7. How high exactly do you have to raise the transom?- - Outboard Jets In the second photo, we've measure down from the top of the Detwiler "brackets". Anything bigger than that your obviously going to need an extra long shaft. You can order an outboard in lengths ranging from 15 inches to 30 inches, depending on its power output and possible uses. 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). If the propeller fails to ventilate, the motor is mounted to low. Beefier jack plates can be fitted should a boater be looking to mount an outboard with a shorter shaft than their transom demands. If you have an outboard motor, the distance from one end to another will be found on the side or on a label near its bottom. ), Al Shields Not to measure boat speed, but to gauge the mounting height of the outboard motor on the boat transom. One of the main concerns is causing the engine to overheat if not enough water reaches the engine to keep it cool. This will ensure the best performance. Beginning boaters should be aware of the boats measurements. While this is the case there is certain saltwater motors that are extra extra long at 30 and 35 shaft. A2: Instead of changing to the short outboard shaft, you can try the Jack Plate first. Bass boats, ski boats, or center cockpit vessels will want to double-check their measurements to get it just right. (In the case of the faster It was a 23-foot Crestliner Grand Cayman pontoon boat. actually have the propshaft above the pad.). This is also known as the shaft length. Lubrication System Engine Oil Mixed Gasoline. Using your existing control box and gauges will save you quite a bit of money in the end. Check the literature about your model boat online, and you may be surprised to find that the number is published for you. This, however, is not recommended for the beginning boater. The distance between the ends of a transom is measured in inches. Increased RPM and additional horsepower feed the need for speed. %PDF-1.7 Measure from the top of the straight edge to the center of the front However, there may be times when a boater strays away from these recommendations. It can also improve the experience of driving a faster boat. Among them will be first-timers or those who have recently purchased their boats. There are a series of four to six holes at the top of the bracket, and the lower bolts actually fit into slots. 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? All things considered, sticking with the industry standard is best for the beginner. The cookie is used to store the user consent for the cookies in the category "Analytics". However, youll notice a little increase in drag and a decrease in top-end performance. The performance of these boats depends on quite a lot of factors, but getting the outboard length just right is an essential first step. Check out some hot FAQs to help you get the proper outboard shaft lengths. I show you how to consistently measure your prop to pad height. since 1986. Boaters who consider going with a higher mount can see increased speeds. The clamp bracket on the latest Mercury Four-Stoke-model outboards has five mounting bolt holes spaced .75 inches apart. the aluminum plate on top of the transom), to the bottom of the motor Boaters who consider going with a higher mount can see increased speeds. from the transom. If we run into that scenario, I would still show you the different options of motors and go over pricing, but I would also ask you to hold off and do one thing before you pull the trigger. Other boats that need extra long shafts are: Read my other articles on outboard motors. It is extremely important that the boater understands the significance of the transoms height. All things considered, sticking with the industry standard is best for the beginner. For example, you can have the Mercury outboard shaft length by model code. A retired ship captain, Charpentier holds a doctorate in applied ocean science and engineering. var h = d.getElementsByTagName("head"), A reversetransom that sits too high can impact the propellers of the motor and motor bracket. High powered boats usually only come in long and extra-long variants. As a dealer I run into this situation from time to time, which is fine but getting the right length outboard for your boat is crucial. A: The short answer is Yes. How the outboard will sit on the back of the boat depends on how the transom is designed. But in many cases, its a little more complicated than that alone. Boat transom angles play a pivotal role in the flexibility of the boats trimming abilities. This measurement was approximately 4". stream Place the bracket on the transom to the left of the main outboard or rudder. The height of the boat transom dictates the size of the outboard motor. To do so, measure from the stern (back) of the boat to the midpoint of the hull on both sides. Follow Westshore Marine & Leisure on Twitter! A long shaft engine requires a height of 20 and extra-long shaft engines will need a transom height of 25. Generally, the anti-ventilation plate on most engines is aligned with the bottom of the vessel. var BCData = {"csrf_token":"d7ecb6b56891bb66aee12dbc01a80162b3ed582c1acbe30f16fc9f1b2abc362f"}; Most of the standard engined boats it takes shafts that are 15-30inches long. }, 100); When trimming your motor, they provide you a greater bow response. motor brackets 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. Move the bracket as close to the center of the transom as possible while still maintaining clearance to allow the main outboard or rudder to reach its full range of motion without contacting the kicker motor. The outboard comes with mounting holes and brackets. Should I take the raft onto the water and measure the exact distance from the top of the transom to the water line? 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. Some outboards have a serial number that tells you which shaft length to go for. Read the measurement on the transoms bottom. straight edge on the top of the transom to "extend" it out Of course, its always best to go with standard practices when choosing thebest boat engine. These two measurements will give you the length of the shaft you need. Then, you can pick the right engine. So if you are measuring the outboard shaft length for the powerboat, planing boat, or any boat for which the speed is the priority, take the outboard shaft length 1 to 1.5 (depending on your boat types) shorter than standard would be better. Or it can have an angle degree as high as 30. 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. There is a simple test to see if your outboard motor is set at the best height. To do so, you will want to measure at the exact center of the transom from the very top to the very bottom. However, there may be times when a boater strays away from these recommendations. 5/rC,aQhsK@Q. minAmount: 300.0, var ptScript = "https://cdn.paytomorrow.com/js/pt-mpe.min.js"; Plus, a low transom cut is an invitation for the water to flood the boat. Buying a boat can be an exciting purchase. (function () { Higher mounting decisions should be left to the professionals.