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. This website uses cookies to improve your experience while you navigate through the website. ), and place it on the bottom of the pad in the center. MPW eBay Store - Thousands of New OEM Old Stock Parts! By clicking Accept, you consent to the use of ALL the cookies. This cookie is set by GDPR Cookie Consent plugin. Extra-long shafts are 25-inches long. var prefix = 'ma' + 'il' + 'to'; For example, you can have the Mercury outboard shaft length by model code. Bass boats, ski boats, or center cockpit vessels will want to double-check their measurements to get it just right. xmlHttp.send('{"store_id":"369079","timezone_offset":"-5","timestamp":"2023-03-04T05:39:31.71020200Z","visit_id":"e2642be3-34e5-4a48-b89d-639d139834e0","channel_id":1}'); 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 cookie is used to store the user consent for the cookies in the category "Performance". "brackets". Mounting the outboard motor in accordance with the industry standards is important. Be sure to measure carefully and research thoroughly before diving in. You need JavaScript enabled to view it. Your goal is to measure how the outboard will sit, so start from the clamping plate and follow the centerline of the hull. Generally, the anti-ventilation plate on most engines is aligned with the bottom of the vessel. If you are running a slower boat, the exact location of the ventilation plate is less important. With the outboard shaft length too long, meaning the prop is too deep in the water, the engine wont be as efficient, and the fuel burn is high. var addyd53b59933f6c3f2e8b59f1b4a6d41fa5 = 'info' + '@'; A deep Vee hull will result in a different measurement than a flatter . The distance between the ends of a transom is measured in inches. (In the case of the faster Youll need a short shaft outboard if its 15 or less than an inch shorter. Raising the motor increases the speed of the boat while decreasing the effort needed to turn the boat. var xmlHttp = new XMLHttpRequest(); Check out the full chart of the Mercury outboard model code and its features. endobj There are instances where a lower mount may be okay. I believe 20 to 21 inches is the optimum length for a lengthy shaft. I would ask you to go back and measure the transom of your boat. enableMoreInfoLink: true, s.setAttribute("src", script); Ill also explain the difference between short and long shafts and how they vary by type of boat. You'll need a short shaft outboard if it's 15 or less than an inch shorter. There is a simple test to see if your outboard motor is set at the best height. In addition, motor totes will not harm the finish of the lower unit. It is where the outboard is mounted, and some boat owners place the name of the boat. will be to the flat part; if you measure to the bottom of the brackets https:/. ensure that your measurement is accurate. For most boaters this is a no brainer, but for the novice or inexperienced boater it may be a tougher question. It doesnt matter if you have a fiberglass boat, bay boat, big or small boat. Some fishing boats can handle the motor being underwater. If you decide to make adjustments, please consult a marine engine dealer about the boat design. })(); With it comes a lot of responsibility and new things to learn including boat maintenance and boat basics. As a result, the issue is whether my boat need a short shaft or long shaft motor. 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. Next, measure from your centerline to where the outboard will be mounted on each side. straight edge from the center of the pad, but this time you're measuring Smaller boats may use adjustable jack plates that can be changed to fit any outboard. Pad to bottom of The most common percent angle is probably 12, however spec sheets for O/B and I/O boats may show 10 percent, 12 percent, and 14 degrees. You I run a 9.9 Mercury Bigfoot 20" shaft off the swim platform of my 89 Trophy 2160. 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. 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. height (that I'm aware of); probably the most common is: AztH ^zv_ cT,E1K/rAB54| These allow the mounting of a standard length outboard behind the transom. Smaller inflatables and dinghies needshort shaft motors, whilst bigger boats require long or, in some circumstances, extreme long shaft versions. Another important measurement is the transom angle. 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. Or measure from the main engine prop up to the water line? I mean it is better to be safe than sorry, am I right? 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. } <>/ExtGState<>/XObject<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 595.2 841.8] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> How do you measure a transom on an outboard motor? To do so, you will want to measure at the exact center of the transom from the very top to the very bottom. Finding the right size is a matter of looking at what youve got and taking out the measuring tape. Doing this can have adverse effects. Add yours in the comment and Ill get back to you asap. 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". 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. Recommended Engine Oil 2-Stroke Outboard Motor Oil. Take your time and understand your boat and your entire transom. When trimming your motor, they provide you a greater bow response. Then, you can pick the right engine. The clamp bracket on the latest Mercury Four-Stoke-model outboards has five mounting bolt holes spaced .75 inches apart. 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. This cookie is set by GDPR Cookie Consent plugin. (Any measurement given as "off the transom" The transom angle is the vertical incline of the transom and is measured in degrees. Also, the boat will be more likely to hit bottom or submerge objects such as rocks or logs. This is a measurement that has been used for BassCats, I'm Attention: Remember to measure the outboard shaft length straight up and down instead of measuring along the transom. This cookie is set by GDPR Cookie Consent plugin. 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 do so, take a measurement from the very top to the very bottom of the transom in the precise center. Keep these numbers in mind if you ever have a need for a new outboard motor for your boat. If it measures 15" or with in a inch of that you will need a short shaft outboard. Smaller 12-14 foot boats can require either a short or long shaft outboard depending on the style of the boat and the brand. Step 4. It is extremely important that the boater understands the significance of the transoms height. jackplate to a point level with the top of the transom. Like Westshore Marine & Leisure on Facebook! 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. 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. Will Charpentier is a writer who specializes in boating and maritime subjects. I would also recommend finding your maximum horsepower rating which is located on the yellow coast guard tag towards the back of your boat. These cookies ensure basic functionalities and security features of the website, anonymously. 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. What are Apple Podcasts Subscriptions and Channels? Gear case sits just below or at the hull depth due to the deep v. Oftentimes you will want to adjust the outboard shaft length in order to improve the boat performance such as speed. Take your time and understand your boat and your entire transom. Any questions? e-mail See When St. Peters Basketball Games Are Today! This could also affect your travelling capabilities on the boat trailer. 12 Small Fishing Boat Accessories to Buy Today. of the "bullet" on your lower unit. mpeInit(); If you have already measured you transom tip to bottom to be 20", then if you place aux sdieways to central engine your available transom height will be probably 1"-1.5" " higher and work perfecty. How the outboard will sit on the back of the boat depends on how the transom is designed. mpeSelector: ".pt-mpe", Whether you already own a boat or looking for your first watercraft we are here to service your needs. If youre looking for a bracket that can handle motors of up to 10/15 horsepower, go no further. There are instances where a lower mount may be okay. trimming the motor out by one-half to full trim. Step 3: Add another 10 cm (4'') to the previous calculation for the final ideal shaft length. If it measures between 17 and 22, youll want to go with a long shaft motor. It also cuts into speed and fuel efficiency. Knowing the width, height and depth of your transom allows you to make several important decisions when selecting or purchasing a new outboard.