will be to the flat part; if you measure to the bottom of the brackets 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. For example, you can have the Mercury outboard shaft length by model code. PayTomorrow.mpeInit({ The transom is the rear wall of the boat where the outboard engine is mounted in the middle. If you are looking to repower, they may be able to offer some sage advice. s = d.createElement("script"); var path = 'hr' + 'ef' + '='; Owners of bass boats, RIBs, or offshore fishing boats need to get this right. Trimming in, trimming down, and trimming out are all terms that a beginning boater should learn. Propshaft in Gear case sits just below or at the hull depth due to the deep v. It doesnt matter if you have a fiberglass boat, bay boat, big or small boat. It was a 23-foot Crestliner Grand Cayman pontoon boat. This will be the var interval = setInterval(function () { Oftentimes you will want to adjust the outboard shaft length in order to improve the boat performance such as speed. You loadScript(ptScript); These two measurements will give you the length of the shaft you need. Any questions? Anything bigger than that your obviously going to need an extra long shaft. Keep these numbers in mind if you ever have a need for a new outboard motor for your boat. Raising the motor increases the speed of the boat while decreasing the effort needed to turn the boat. 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. The correct shaft length for your boat depends on a few factors. stream All things considered, sticking with the industry standard is best for the beginner. The outboard comes with mounting holes and brackets. This could also effect your travelling capabilities on the boat trailer. 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. If it measures 15" or with in a inch of that you will need a short shaft outboard. 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. In the photo above, we've measured from the motor bracket to the top of Chances are the boat was designed with a specific size of outboard in mind. A long shaft engine requires a height of 20 and extra-long shaft engines will need a transom height of 25. 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. To measure the transom height, measure from the center on for transom (rear of the boat). of the motor off the transom When trimming your motor, they provide you a greater bow response. Since the length of the shaft of your outboard is associated with the size boat, smaller engines will generally have shorter shafts. Whether you already own a boat or looking for your first watercraft we are here to service your needs. A: Any boat that has a 21 to 27 inch aft transom will need an extra long shaft outboard. A yardstick will help you determine if your outboard engine is at the right height. This is measured by the propeller shaft being parallel to the vessels bottom. }, 100); 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. Most transom savers can support up to a 150HP motor, which is sufficient for most regular boats. However, there may be times when a boater strays away from these recommendations. endobj The transom is the "back wall" of your boat, the most rearward part of your hull. The clamp bracket on the latest Mercury Four-Stoke-model outboards has five mounting bolt holes spaced .75 inches apart. Measuring Motor Height - BassBoat Central minAmount: 300.0, In step 3, add another 10 cm (4") to the previous calculation in order to develop the ideal shaft length. However, there may be times when a boater strays away from these recommendations. Tilt your motor until the bullet of the gearcase is |. If you decide to make adjustments, please consult a marine engine dealer about the boat design. Then, you can pick the right engine. Well, raising the outboard motor can be an easy task for you. By clicking Accept, you consent to the use of ALL the cookies. 4 0 obj Then adjust the motor in a higher hole with a flat head screwdriver. Analytical cookies are used to understand how visitors interact with the website. It also cuts into speed and fuel efficiency. 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. var BCData = {"csrf_token":"d7ecb6b56891bb66aee12dbc01a80162b3ed582c1acbe30f16fc9f1b2abc362f"}; % While this is the case there is certain saltwater motors that are extra extra long at 30 and 35 shaft. manufacturer will recommend the outboard height according to the bracket shape and length. On this type of boat, if you are in doubt, default to the longer-shafted outboard. If you are running a twin-engine setup, then measure the same distance from each clamping plate to the bottom of the hull. Here we will guide you in how to get the right boat transom height. 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". Tightening Torque for Engine. The prop will be in cleaner, harder water as it advances farther aft, making it more efficient. On most newer center consoles and offshoreboat transoms might include a rear door leading to a swim platform as well as a molded setback bracket. 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. Thats a fairly simple list of symptoms, but if your motor is too low, youll probably notice at least one of them. You can order an outboard in lengths ranging from 15 inches to 30 inches, depending on its power output and possible uses. 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. Another important measurement is the transom angle. To sum up, there is a simple calculator of the shaft length for outboard motors: Outboard Shaft Length = Transom Height +/- Factors. Whether your on a pontoon boat, fishing boat, or speedboat boating is always one of the best times you can have. How to Buy a Boat: Tips for a First Time Buyer, Top 10 New Fishing Boats for Under $20,000, What Type is Right for You? Remember, if you use a longer outboard shaft than you need you will be increasing your draft. Place the point of a yardstick at the middle of the top of the boat transom. 1 0 obj Measure from the top of the straight edge to the center of the front Finding the right size is a matter of looking at what youve got and taking out the measuring tape. When the boat transom is too low, the motor could end up underwater. Motor height on pontoon? | Boating Forum - iboats Boating Forums As a result, the issue is whether my boat need a short shaft or long shaft motor. This is handy if youre shopping for second-hand outboards or looking to sell the one that came with your boat. Outboard shaft length plays a crucial role in the performance of your boat. 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. help with shaft length for a kicker - iboats Boating Forums How the outboard will sit on the back of the boat depends on how the transom is designed. 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. 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. Also, the boat will be more likely to hit bottom or submerge objects such as rocks or logs. There are 2 steps to help get a relatively accurate figure. 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. Outboard Motor Shaft Length: How do I measure? Why wont Touch ID be under the screen in the iPhone 15 and iPhone 16? Some fishing boats can handle the motor being underwater. A: The answer varies by boat, but here are some rules of thumb for matching a short shaft outboard to your boat. }) } }); })(document); Having the cavitation plate too low will cause excess drag and reduced performance at high speeds. 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. What is the Virtual Sundance Film Festival? Having the cavitation plate a bit lower than the transom is preferable to having it too high. straight edge on the top of the transom to "extend" it out Simply start with the engine in idle, followed by trimming the motor out by one-half to full trim. 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. No one wants to have issues with a new transom or boat repairs. All boats are different, and the motor manufacturers produce a variety of standard lengths. Eq*^?6R83e+j}UY.(M7k]~4g)g ~wmS{ O7t/o(W|X? Get the latest updates on new products and upcoming sales, 2023 Marine Parts Warehouse Incorporated endobj Safely but briskly accelerate. Doing this can have adverse effects. To achieve this, the motor itself has to be attached at the correct height. Although the longer outboard shaft length can lead to lower speed and more drag, the boat can push a heavier load. Your email address will not be published. displayMicroOffers: false, If mounting directly to a boat transom: Measure from the top of the transom down to the bottom of the hull or keel (lowest point). On the downside, a higher mount can interfere with the boaters steering capabilities. Boat hulls are designed in three basic types that range from slow displacement and semi-displacement hulls to the fastest planing hulls. 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. Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet. Simply start with the engine in idle, followed by, If you decide to make some custom adjustments we have the. Displacement hulled vessels like sailboats and workboats can benefit from a little more space between the hull and cavitation plate, but not much. So how to measure outboard shaft length? (616) 364-0666, On all contiguous US part orders over $100. xmlHttp.open('POST', 'https://bes.gcp.data.bigcommerce.com/nobot'); Engine Oil Mixing Ratio Fuel 50: Engine Oil 1. Which Navigation Lights Does Your Boat Need? 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? In the case of a larger offshore boat, it may be to the top of a cutout on the . The height of the boat transom dictates the size of the outboard motor. Measuring the shaft length can be done in various ways, but the most common way is by using a tape measure. %PDF-1.7 With it comes a lot of responsibility and new things to learn includingboat maintenanceand boat basics. var addyd53b59933f6c3f2e8b59f1b4a6d41fa5 = 'info' + '@'; Outboard Motor Shaft Length For Pontoon Boat - Survival Tech Shop In extremes, the engine can have overheating problems if the boat is raised to a point where the water inlets for the cooling system are out of the water. This is somewhat similar to #2, in that you are again measuring with a As a yacht designer and boater, I prefer longer shafts. Check out the full chart of the Mercury outboard model code and its features. 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. Again, make sure that you are measuring to the flat part of the brackets; If your boat planes, pay extra attention to getting the shaft length as close to perfect as possible. Industry standards dictate that for short shaft engines the transom height should be 15. This measurement was approximately 4". Follow Westshore Marine & Leisure on Twitter! It also includes attaching the right engine. So from there, I will try to help out by asking questions about your boat such as what type it is and the length. (function (d) { How-To: Pick A Great Portable Outboard Motor (2023 Guide) What are Apple Podcasts Subscriptions and Channels? In the case of a dinghy or johnboat, this point may be the top of the transom. Long shafts are 20-inches long. How Transom Height Is Measured This is measured by the propeller shaft being parallel to the vessels bottom. All you need to do is measure how much to rise. var xmlHttp = new XMLHttpRequest(); The greater the number, the more the drive may sway (also called tuck under or negative trim). })(); Mounting the motor lower on the boat transomcan createexcessive spray, increase case drag, reduce underwater clearance, and negatively impact faster boats. Place the rulers end on the ground behind the club and let the club to rest on top of it. It also decreases the boats lift and increases the time it takes for the boat to reach plane. MPW eBay Store - Thousands of New OEM Old Stock Parts! All rights reserved. Doing this can have adverse effects. The motor length corresponds to the transom height of the boat, measured from the keel to gunwale at the transom. If the height of the boat transom is off it can cause major issues. straight edge from the center of the pad, but this time you're measuring As mentioned above, the operation of the propeller relies on the transom height. The performance of these boats depends on quite a lot of factors, but getting the outboard length just right is an essential first step. His works have appeared in regional newspapers in North Dakota and in "North Dakota Horizons" and "Cowboys and Indians" magazines. Since the ventilation plate & foil are burried under water it is obviously too low. However, your boat will have slightly more drag which will reduce your maximum speed. Read the following to get the optimal shaft length for outboard motors! The pros and cons of properly . One of the main concerns is causing the engine to overheat if not enough water reaches the engine to keep it cool. 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. Outboard Motor Shaft Length - LeeRoy's Ramblings Take your time and understand your boat and your entire transom. Its still smart to measure it yourself though, just in case, the design changed over the years. Its important to note that manufacturers call their models different things. Will Charpentier is a writer who specializes in boating and maritime subjects. No one wants to have issues with a new transom or boat repairs. When mounting the engine, you want the cavitation plate to be 1 above the boat bottom for every 12 away from the transom. Set the end of the tape on the outside edge of the taffrail at the center and measure inward to the inside edge of the taffrail. The form of a boats transom varies depending on the manufacturer and model. s.setAttribute("href", "https://cdn.paytomorrow.com/css/pt-mpe.min.css"); It is possible that the motor could hang low while transporting on the boat trailer causing future boat repairs. However, with the outboard shaft length too short, meaning the prop is too close to the surface, the engine is likely to ventilate and therefore slip on acceleration or lose power. Check out some hot FAQs to help you get the proper outboard shaft lengths. Engine height with stepped hull at transom - before I screw things up The propellers will also have trouble reaching the water. You need JavaScript enabled to view it. This also means it can affect the safety of the boat. What Types of Documents Can be Sent to your Kindle Library? jackplate to a point level with the top of the transom. 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). You need JavaScript enabled to view it. Transom Outboard Engine Position - YouTube Add yours in the comment and Ill get back to you asap. Extra-long shafts are 25-inches long. debugMode: false, A deep Vee hull will result in a different measurement than a flatter . Place the clubs bottom on the ground as though it were going to be used to strike a golf ball. How can you figure out what your transom angle is? Is my outboard long or short shaft? <> Some may call it a standard length while others may call it a short or a long shaft. Step 3: Add another 10 cm (4'') to the previous calculation for the final ideal shaft length. 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. } If your outboard motor height. This, however, is not recommended for the beginning boater. The boat transom can be flat with zero degree angles. The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. As with anything, there are exceptions to the rule. Or it can have an angle degree as high as 30. The dealer just hit you with the long or short shaft question and you have no clue as to what you need or even what he's talking about. The standard shaft length for most outboard engines less than 125 horsepower is 20 inches. 2 0 obj Generally, the anti-ventilation plate on most engines is aligned with the bottom of the vessel. Cavitation plates are used on the bottom components of boats to help them operate better. Cutting the transom down is the only legal method to utilize a short shaft engine on a tall transom. When the boattransom is too low, the motor could end up underwater. 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. 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. Shaft lengths are available in increments of 5. To achieve 35 mph with a 6 hp engine, the total weight is 135 lbs (boat motor fuel passengers). priceSelector: ".price--withoutTax, span.price.price--withTax", The first order of business is to measure your boat for the ideal fit. (127 mm). C Cheaptoon Cadet Joined Aug 4, 2010 Messages 28 Aug 24, 2010 #4 Re: Motor height on pontoon? if (PayTomorrow) { If youre going the other way around and trying to figure out how long the shaft on your outboard is, measuring it is equally easy. These cookies track visitors across websites and collect information to provide customized ads. It can also improve the experience of driving a faster boat. 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. gtag('js', new Date()); They keep water out of your prop and increase water pressure in the system. He is also a certified marine technician and the author of a popular text on writing local history. How to Find Your Shaft Length | ePropulsion The how to measure the shaft length of an outboard motor is a question that many people have asked. Save my name, email, and website in this browser for the next time I comment. Whether you already own a boat or looking for your first watercraft we are here to service your needs. You must be still in the blue about that matter. This restriction includes most fishing boats and longer sailboats. The cavitation plate 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. How high exactly do you have to raise the transom?-. With some boats I have a pretty good idea as to what length motor should be hung on them. #1: Height The transom angle is the vertical incline of the transom and is measured in degrees. What Kind of Fuel Does Your Marine Engine Need? So you should just measure the height of the boats transom from the center down to the lowest point of the hull, and compare transom height with the outboard shaft length numbers. logoColor: "original", Next, measure from your centerline to where the outboard will be mounted on each side. It also cuts into speed and fuel efficiency. Necessary cookies are absolutely essential for the website to function properly. For most boaters this is a no brainer, but for the novice or inexperienced boater it may be a tougher question. For slower boats, its less critical to. This is the dimension you'll need when selecting a width for your outboard motor's mounting bracket. *The Factors indicates the adjustment affected by on your boat type, the outboard working environment, and the transom distance as discussed above. #2. For really big boats, the biggest and baddest six- or eight-cylinder outboards can have extra-extra long shafts up to 30 inches. As summer approaches there will be more boaters taking to the water. The transom in a boat today is a place to hang your outboard motor. Depending on the manufacturer, size names might change. If your boat is newer and the manufacturer is still in business, you might also want to try to give them a call. It is unsafe to have the engine block too close to the water on a low transom. Most of the standard engined boats it takes shafts that are 15-30inches long. Whats the best height for my boat motor? This email address is being protected from spambots. A2: Instead of changing to the short outboard shaft, you can try the Jack Plate first. To do so, you will want to measure at the exact center of the transom from the very top to the very bottom. Higher mounting decisions should be left to the professionals. The cookie is used to store the user consent for the cookies in the category "Other. At least if its too long you can raise the motor or "build up" your transom. Smaller inflatables and dinghies needshort shaft motors, whilst bigger boats require long or, in some circumstances, extreme long shaft versions. var addy_textd53b59933f6c3f2e8b59f1b4a6d41fa5 = 'info' + '@' + 'vanssports' + '.' + 'com';document.getElementById('cloakd53b59933f6c3f2e8b59f1b4a6d41fa5').innerHTML += ''+addy_textd53b59933f6c3f2e8b59f1b4a6d41fa5+'<\/a>'; If it measures 15" or with in a inch of that you will need a short shaft outboard. What matters is the actual measurement in the specifications, not the name. What's the best height for my boat motor? d.addEventListener("DOMContentLoaded", function (e) { h[0].appendChild(s); These cookies ensure basic functionalities and security features of the website, anonymously. 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. It is extremely important that the boater understands the significance of the transoms height. It doesnt matter if you have a fiberglass boat, bay boat, big or small boat. It moves an outboard up and down to optimize performance and enable a boat to venture into shallower water than it might otherwise. With the long side (22 1/2), place a carpenters square ) in opposition to the keel. If you have a small boat with a 15 to 17 inch aft transom, youll most likely need a short shaft outboard. https://www.bornagainboating.com/Get Your Born Again Boating Clothing! If so, send me an Copyright 2017 Dealer Spike All Rights Reserved.