Yamaha Outboard Trim & Tilt

Yamaha Marine Engine Trim & Tilt Components Resources and Information

Yamaha marine trim & tilt components adjust the motor's angle and the boat's running surface. These essential components determine the smoothness of the ride, the boat’s grip on the water, its ability to jump on a plane, and many other operations. If you need help finding the right trim and tilt switch for your outboard, check out our Yamaha Trim and Tilt Switch Selection Chart.

In addition to outboard trim and tilt components, we’re also proud to offer a complete selection of Yamaha outboard parts. 

Need help servicing your Yamaha outboard engine? We provide to following resources to help service your Yamaha outboard engine: 

• Yamaha Outboard Service Schedule
• Yamaha Outboard Engine Schematics
• Yamaha Outboard Maintenance Parts Charts

Yamaha Outboard Trim & Tilt Components FAQs

What are the signs of faulty Yamaha trim and tilt problems?

Are you having problems with the trim and tilt switch of your Yamaha F115?

Contrasting with the internal engine problems we’ve covered so far, trim and tilt problems are external. Trim and tilt involves how well your boat is propelled through the water by the angle of the propeller shaft relative to the boat. A faulty trim and tilt switch can prevent you from the fine-tuning (trim) and dramatic changes (tilt) needed for optimal performance of your Yamaha F115, including:

• Poor gas efficiency due to friction/drag of the water
• Lower RPMs, acceleration, and overall top speed
• Less accurate control during operation
• Inability to raise the motor for storage, servicing, and/or removal

Luckily, you can avoid these problems by swapping out the trim and tilt switch as needed. However, keep in mind that a faulty trim/tilt switch can be a sign of some other issues, such as low battery, electrical shorts, malfunctioning hydraulic motors, and more.

How do I install a trim tab anode on my Yamaha outboard engine?

Now that you understand why trim tab anodes are important for your boat and outboard motor, let’s learn how to install trim tab anode on Yamaha outboards:

• First, identify where the trim tab anode on your Yamaha outboard is. It is typically located above the propeller on the anti-cavitation plate.
• Next, locate and remove the trim tab plug located directly above the trim tab. 
• In the cavity, you will insert a socket wrench with an extension to access the bolt securing the trim tab. Most Yamaha trim tabs use a ½” socket wrench.
• Make a note of the hash marks by the trim tab, which indicates how many degrees they will be offset. Use a piece of masking tape if you have to remember the location so you won’t have to adjust it after installation.
• Slowly turn the bolt counterclockwise to loosen the trim tab until it loosens.
• Insert the new trim tab anode. Replacement is the opposite of installation.

That’s the entire process for replacing a trim tab on a Yamaha outboard motor. Simple!

Now that you know how to install trim tab anode on Yamaha outboards, an outboard trim tab anode adjustment only requires a loosening of the retaining bolt and adjusting according to the hash marks.

Simply adjust the trim tab in the direction it is misaligned – if your boat steers too much to the starboard side, adjust the trim tab right; vice versa for port-side steering. As a word of caution, only make adjustments in one-click increments. Also, make sure the trim tab anode is secure, as a loose trim tab can stray from its original position.

What does the trim tab anode do on my Yamaha outboard motor?

Trim tabs are essential for steering your boat safely and accurately. When properly aligned, trim tab anodes counteract torque pressure generated by the propeller for steering and helps even out “prop-walk,” a propeller’s tendency to rotate about a vertical axis. That’s why it’s called a “trim” tab, enabling a more stable ride that offsets unwanted torque. Trim tabs are often set at an offset angle for this purpose – aligned right for right-turning outboard motors and left for left-turning outboard engines. Most Yamaha outboards have a series of hash marks by the trim tab that indicate the offset needed for accurate steering.

There are three types of corrosion boaters typically experience:

• Simple electrochemical corrosion
• Galvanic corrosion
• Electrolytic/stray current corrosion

Trim tab anodes absorb these types of corrosion more readily than other engine components, so they serve as a protective barrier to save more expensive and harder-to-repair parts. 

Over time, these anodes—typically made of cheap zinc materials—will degrade and need to be replaced. As the material degrades, it begins to lose some of its steering abilities and its ability to attract corrosion. While simply cleaning it with a wire brush will restore it for minor damage, replacement is necessary when corroded to approximately half of its original size. This is why they are referred to as sacrificial anodes—the anode sacrifices itself to protect your engine and its components. 

Checking your trim tab anode(s) (and other anodes, for that matter) should be done minimally as part of your annual or 100-hour service.

How do I service my Yamaha outboard lower unit?

Yamaha lower unit gear lube is drained by removing the lower drain screw first and then the upper plug vent to allow air in. On most models, both plugs are clearly visible on the lower unit, but on models with low water pickups, the forward pickup will need to be removed to access the drain plug. Use a properly sized screwdriver assisted by a wrench if necessary to loosen these screws which should be pretty tight. An impact driver and hammer may be needed depending on who serviced your engine last. The drain screw has a magnetic tip, so inspect the plug after removal to see if heavy deposits exist. Some fine shavings are normal, but chunks or a large quantity of metal is cause for further inspection. Have a drain pan and extra rags handy as gear lube will begin running down the skeg as soon as you remove the upper vent plug. Be sure to collect the fiber gaskets from both plugs after removal, as these are not reusable and should be discarded.

Allow several minutes with the engine tilted all the way down to fully drain the old gear oil. Like your engine oil, inspect the spent oil for evidence of water intrusion or other contamination or metal. If you have purchased one of PartsVu’s handy lower unit oil change kits you will already have new gaskets, oil, and a pump. Screw the pump into the lower drain hole and then connect it to the quart of Yamalube gear oil or HD gear oil depending on your model. Begin pumping oil into the lower unit until oil begins to flow from the vent plug at the top. Stop pumping and wait a few minutes for all the air bubbles to work themselves out of the gearcase. After this brief pause, pump a few more pumps until clean gear oil without bubbles is flowing from the vent plug. With a fresh fiber gasket in place, install and torque the top vent plug. Unscrew your fill hose from the lower drain plug and quickly swap in the lower drain plug with a new gasket. Torque to spec and re-install the lower water pickup screen if applicable.

How do I choose the right propeller for my Yamaha outboard motor?

Your propeller decision-making process will include the following factors: pitch, diameter, aluminum or steel, blade number, rake, cupping, and rotation. 

Pitch is a critically important factor when selecting a new propeller. Pitch is the distance the prop would travel forward after one complete rotation, assuming no resistance or slip. 

If you need more speed, a higher pitch is generally the way to go. However, If you use a propeller with a too high pitch, the motor won’t have enough horsepower to turn it adequately, so the revolutions per minute will drop. Referred to as over-propping, it overloads the engine and causes excessive wear. Under-propping—fitting a propeller with too low a diameter or pitch—can damage your engine through over-revving. Under-propping will also adversely affect fuel consumption. 

A larger diameter propeller reduces the RPM and top-end speed. On the other hand, smaller diameter propellers increase RPM and top-end speed. However, smaller diameter props slip more frequently and are not good choices if hole-shot or acceleration improvement is your goal. 

Aluminum propellers are the most common and the least expensive. Stainless steel propellers are more durable and generally perform better due to both thinner and stiffer blades.

Most commonly, propellers have either three or four blades. Three-blade propellers are most common on general use recreational boats. With only three blades in the water, they encounter less resistance increasing fuel efficiency, and they generally have minimal impact on your outboard engine’s RPM. 

Four-blade propellers improve hole-shot acceleration; therefore, commonly used on ski boats. These props improve handling and are generally better in rough water.