Disclaimer: As an affiliate I may earn a commission on any qualifying purchases, including those from Amazon.com, at no extra cost to you read more. We also use third-party cookies that help us analyze and understand how you use this website. minAmount: 300.0, %PDF-1.7 Most of the time, adding a hydrofoil to an outboard improves performance. 2019s List of the Best Recreational Pontoon Boats for Sale. This measurement is primarily designed for single motor propulsion. disregard the downward pointing "hooks" at the front of the <> 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. If the height of the boat transom is off it can cause major issues. In the case of a dinghy or johnboat, this point may be the top of the transom. 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. This is the dimension you'll need when selecting a width for your outboard motor's mounting bracket. Amazon has plate extensions to allow adjustments without buying a new motor: T-H Marine Jack Plate Extension. (127 mm). Engine Oil Mixing Ratio Fuel 50: Engine Oil 1. Small motors built for sailboats might come in a unique configuration with an extremely long shaft since these are mounted higher off the water. 2 0 obj A retired ship captain, Charpentier holds a doctorate in applied ocean science and engineering. 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. You dont have to be a mathematician to determine the correct boat transomangle. In the second photo, we've measure down from the top of the Detwiler Buying a boat can be an exciting purchase. Small portable outboards ranging from 2 to 20 horsepower are usually sold only in short or long shaft versions. Boats with more engine power and weight require longer shaft outboards for better balance. Before we start measuring the outboard shaft length, lets get it clear about whats referring to when we talk about the outboard shaft length. Problems with getting the ventilation plate too low include slower hole-shot and lower top-end speeds. It doesnt matter if you have a fiberglass boat, bay boat, big or small boat. Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. A yardstick will help you determine if your outboard engine is at the right height. (616) 364-0666, On all contiguous US part orders over $100. For over five years he has worked as a newspaper reporter and historic researcher. The transom is the "back wall" of your boat, the most rearward part of your hull. the propshaft below or above the pad. Anything bigger than that your obviously going to need an extra long shaft. will be to the flat part; if you measure to the bottom of the brackets Cutting the transom down is the only legal method to utilize a short shaft engine on a tall transom. The distance between the ends of a transom is measured in inches. Each one has a totally different effect on the boats performance. Chances are the boat was designed with a specific size of outboard in mind. to where the brackets were actually resting on the transom. Boat Transom Heights The Beginners Guide, Buying a boat can be an exciting purchase. 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 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). A: The short answer is Yes. Again, make sure that you are measuring to the flat part of the brackets; Measure from the top of the transom to the bottom of the hull. However, you will need an understanding of how the degrees will alter the boats usability. It also cuts into speed and fuel efficiency. relation to pad Place the rulers end on the ground behind the club and let the club to rest on top of it. 1855 Alpine Avenue NWGrand Rapids, MI 49504This email address is being protected from spambots. One of the great things about an outboard motor is how versatile it is. Trimming in, trimming down, and trimming out are all terms that a beginning boater should learn. #1: Height Before we get started lets see what a boat transom is and what it does. would be more accurate.) The brackets can add 1 inch to the overall mounting height of the outboard. % Copyright 2017 Dealer Spike All Rights Reserved. It also decreases the boats lift and increases the time it takes for the boat to reach plane. h[0].appendChild(s); These are vertically aligned so the boater can make adjustments. Other boats that need long shafts are. 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. If you are looking to repower, they may be able to offer some sage advice. Mounting the outboard a little bit lower than the standard point could avoid the possible ventilation and slip on acceleration. 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. Mounting the outboard motor in accordance with the industry standards is important. 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. (function (d) { There are instances where a lower mount may be okay. The same is true for the newest, high-powered offshore fishing boats, where triple or quadruple motor setups are becoming more and more common. For most boaters this is a no brainer, but for the novice or inexperienced boater it may be a tougher question. A hydrofoil will typically level off the ride by driving the stern up and the bow down, and will stop or considerably minimize porposing on a 16 footer with a mid-sized outboard and no tabs, for example. Simply start with the engine in idle, followed by trimming the motor out by one-half to full trim. See When St. Peters Basketball Games Are Today! Check out some hot FAQs to help you get the proper outboard shaft lengths. Knowing how this can affect the overall operation of the boat is a factor to be considered. AztH ^zv_ cT,E1K/rAB54| 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. x\[D~OUCO6[j](l%ay <8cylY{.L2s#]~U6A|Wj]-oo|mubqY6wbY_|!>Z8(RB:RHeTzOGO_=~t\ In addition, motor totes will not harm the finish of the lower unit. They keep water out of your prop and increase water pressure in the system. The average transom angle is around 14 degrees. 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. 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). Buying a boat can be an exciting purchase. Or it can have an angle degree as high as 30. However, youll notice a little increase in drag and a decrease in top-end performance. Well, raising the outboard motor can be an easy task for you. It does not store any personal data. var path = 'hr' + 'ef' + '='; Pad to bottom of This measurement was approximately 4". 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. This alone can outweigh the negatives when deciding to adjust the mount upwards. up to the bottom of the motor brackets, (as in #1). The propellers will also have trouble reaching the water. 12 Small Fishing Boat Accessories to Buy Today. To do so, you will want to measure at the exact center of the transom from the very top to the very bottom. To achieve this, the motor itself has to be attached at the correct height. Check the literature about your model boat online, and you may be surprised to find that the number is published for you. How Transom Height Is Measured If it measures anywhere from 17" to around 22", then your going to want to go with a long shaft motor. Simply start with the engine in idle, followed by, If you decide to make some custom adjustments we have the. The amount of degrees the transom leans back from vertical is known as the transom angle. No one wants to have issues with a new transom or boat repairs. All rights reserved. Keep these numbers in mind if you ever have a need for a new outboard motor for your boat. "brackets". function mpeInit() { It also includes attaching the right engine. Among them will be first-timers or those who have recently purchased their boats. a Detwiler manual jackplate. Why wont Touch ID be under the screen in the iPhone 15 and iPhone 16? One of the factors in determining the height of the outboard is the placement of the exhaust port on the lower unit of the outboard engine. Take your time and understand your boat and your entire transom. 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. Basically, there are three main ways to measure motor For vessels with transom-mounted outboards, you can easily figure out which type of outboard you need to get. This exhaust port should be about 1 inch above the water line when the boat is idling. Which Navigation Lights Does Your Boat Need? Finding the right size is a matter of looking at what youve got and taking out the measuring tape. A1: Broadly speaking, the outboard motor shaft length for pontoon boat, bass boat, or other larger boats should be long shaft. Measure the area of the transom directly where the engine will be mounted. On this type of boat, if you are in doubt, default to the longer-shafted outboard. maxTerm: 36, Rebuilt - What You Need to Know, Lower Unit and Sterndrive Break-In Instructions. I live for the weekends when I can go out on the water and escape the stress of life on land. As mentioned above, the operation of the propeller relies on the transom height. former editor at Boating Magazine and contributor to many national publications If youre looking for a bracket that can handle motors of up to 10/15 horsepower, go no further. The cavitation plate is the horizontal surface of the lower unit immediately above the propeller. ), and place it on the bottom of the pad in the center. But opting out of some of these cookies may affect your browsing experience. So its easier and safer to communicate with the dealer with the exact measurement of outboard shaft length in order to get the right model. The shaft length for outboard motors has nothing to do with the water line. It was a 23-foot Crestliner Grand Cayman pontoon boat. On the downside, a higher mount can interfere with the boaters steering capabilities. 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. However, there may be times when a boater strays away from these recommendations. (Putting a 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. Attention: Remember to measure the outboard shaft length straight up and down instead of measuring along the transom. measuring; you may have to "extend" the flat part of the Ideally, you want the outboards cavitation plate, also called the anti-ventilation plate, to be at the same level as the bottom of your hull. Industry standards dictate that for short shaft engines the transom height should be 15. xmlHttp.setRequestHeader('Content-Type', 'application/json'); 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. A reverse transom that sits too high can impact the propellers of the motor and motor bracket. The faster your boat, the more critical it is to get the sizing just right. As you can see, the measurement is about 2 1/2". 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. To make the yard stick long enough to measure the length of all the clubs, tape the ruler to the top. Boaters who consider going with a higher mount can see increased speeds. debugMode: false, Although the longer outboard shaft length can lead to lower speed and more drag, the boat can push a heavier load. priceSelector: ".price--withoutTax, span.price.price--withTax", If it measures between 17 and 22, you'll want to go with a long shaft motor. Wherever the outboard clamping bracket is, use this as the basis for measurement. It doesnt matter if you have a fiberglass boat, bay boat, big or small boat. C Cheaptoon Cadet Joined Aug 4, 2010 Messages 28 Aug 24, 2010 #4 Re: Motor height on pontoon? storeDisplayName: "Marine Parts Warehouse", steel ruler, etc. } Sluggish speeds, poor handling, heavy spray, porpoising, or even water pushing up into the cowling are all signs that an outboard is set too low. Most of the standard engined boats it takes shafts that are 15-30inches long. The transom is the rear wall of the boat where the outboard engine is mounted in the middle. bracket forward with a straight edge to where you can then measure up 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. Should I take the raft onto the water and measure the exact distance from the top of the transom to the water line? Recommended Engine Oil 2-Stroke Outboard Motor Oil. However, you will need an understanding of how the degrees will alter the boats usability. It is extremely important that the boater understands the significance of the transom's height. Higher mounting decisions should be left to the professionals. Your goal is to measure how the outboard will sit, so start from the clamping plate and follow the centerline of the hull. The form of a boats transom varies depending on the manufacturer and model. Some outboards have a serial number that tells you which shaft length to go for. This could also affect your travelling capabilities on the boat trailer. Where Onboard a Boat is the Transom Located and More About Transom Heights A propeller operates based on the height of the transom. s.setAttribute("rel", "stylesheet"); Remanufactured 4 Cylinder 4-Stroke Cylinder Heads, Remanufactured 6 Cylinder 4-Stroke Cylinder Heads, Trim Relays, Trim Solenoids & Sending Units, Remanufactured V6 & V8 4-Stroke Cylinder Heads, Volvo Cobra SX Bearings and Bearing Carriers, Volvo Cobra SX Driveshaft, U-Joints & Parts, Volvo Cobra SX Transom Assembly & Bellows. e-mail Lubrication System Engine Oil Mixed Gasoline. Get the latest updates on new products and upcoming sales, 2023 Marine Parts Warehouse Incorporated MPW eBay Store - Thousands of New OEM Old Stock Parts! Mounting the outboard motor in accordance with the industry standards is important. This cookie is set by GDPR Cookie Consent plugin. Because of the increased friction, cavitation reduces efficiency. Its where the outboard motor is attached, and its also where some boat owners put the boats name. This would not be a good thing. The cookie is used to store the user consent for the cookies in the category "Performance". mpeSelector: ".pt-mpe", The lowest point will likely be directly under your drain plug if youve got one. Mounting the motor lower on the boat transom can create excessive spray, increase case drag, reduce underwater clearance, and negatively impact faster boats. 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. When the boat transom is too low, the motor could end up underwater. Typical motor lengths include the following. The transom angle is the vertical incline of the transom and is measured in degrees. The motor length corresponds to the transom height of the boat, measured from the keel to gunwale at the transom. clearInterval(interval); Step 3: Add another 10 cm (4'') to the previous calculation for the final ideal shaft length. trimming the motor out by one-half to full trim. If your boat is newer and the manufacturer is still in business, you might also want to try to give them a call. Next, measure from your centerline to where the outboard will be mounted on each side. In step 3, add another 10 cm (4") to the previous calculation in order to develop the ideal shaft length. Always weigh the risks of making adjustments. This could also effect your travelling capabilities on the boat trailer. 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. However, the shaft length for smaller boats could be long or short depending on its style, speed requirement, etc. var interval = setInterval(function () { }, 100); So from there, I will try to help out by asking questions about your boat such as what type it is and the length. Simply start with the engine in idle, followed bytrimming the motor out by one-half to full trim. straight edge from the center of the pad, but this time you're measuring The average transom angle is around 14 degrees. Ten years ago I bought my first boat. It varies between different motors and boats. 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.
