Replacing Yamaha Boat Throttle Cables: A Step-By-Step Guide

If you're having trouble with the throttle on your Yamaha boat, it might be time to replace the throttle cable. This cable is what connects the throttle to the engine throttle plate, allowing you to control the speed of your boat by applying and releasing pressure. There are a few things to keep in mind when replacing your Yamaha throttle cable. First, you'll need to determine the type of engine and control head your boat has. You'll also need to measure the length of the cable to ensure you get the correct replacement. Additionally, it's recommended to replace both the throttle and shift cables at the same time, as they are not the same type of cable. You can find Yamaha throttle cables at various online retailers and marine supply stores.

Removing the old Yamaha throttle cable

Step 1: Prepare for the Removal

Before you begin, ensure you have the correct replacement cable for your Yamaha engine. Refer to your Yamaha user manual or consult a Yamaha dealer to identify the appropriate cable for your specific engine model. It is important to note that there are two types of control cables: OEM-specific and Universal.

Step 2: Disconnect the Battery

Safety is paramount when working on any engine. Before proceeding, disconnect the battery to eliminate the risk of accidental ignition. This will prevent any potential hazards during the removal process.

Step 3: Access the Throttle Cable

Locate the throttle cable by referring to your Yamaha engine manual. It is typically connected to the throttle lever and runs towards the engine. You may need to remove any components that obstruct access to the cable, such as covers or panels.

Step 4: Disconnect the Throttle Cable

Using the appropriate tools, carefully disconnect the throttle cable from the throttle lever. This may involve unsnapping or unscrewing the cable connection. Be gentle to avoid damaging the surrounding components. Once disconnected, set the old cable aside.

Step 5: Remove the Cable from the Engine

Trace the throttle cable from the throttle lever to the engine. Carefully remove the cable from any grommets, guides, or retaining clips along its path. Ensure you take note of the cable routing for installation of the new cable.

Step 6: Clean the Area

Before installing the new throttle cable, it is good practice to clean the area. Use a suitable marine-grade cleaner to remove any dirt, grease, or corrosion buildup. This will ensure that the new cable operates smoothly and reduce the risk of contamination.

Step 7: Dispose of the Old Cable Properly

Dispose of the old throttle cable responsibly, following local regulations for waste disposal. Do not attempt to reuse or repair the old cable, as it may have worn out or failed due to a variety of reasons, including corrosion or metal fatigue.

Now that the old Yamaha throttle cable has been successfully removed, you can proceed to install the new cable, ensuring a smooth and responsive connection between your throttle and engine.

Choosing the correct replacement cable

Firstly, you need to identify the type of engine and control head on your Yamaha boat. This is important because there are different types of control cables available, and you need to select the one that is compatible with your specific engine and control head.

There are two main types of control cables: OEM-specific (Original Equipment Manufacturer) and Universal. OEM-specific control cables have the appropriate end fittings for your particular engine and control head. For example, they might be designed specifically for a Yamaha engine. On the other hand, Universal control cables come with threaded ends and require a separate connection kit that is specific to your engine and control head.

When choosing a replacement cable, it is important to consider the length. To determine the exact replacement length, you can look at the plastic jacket on the original cable. The length will be indicated in either feet or inches, depending on the model. It is important to note that some OEM cables may be in half-foot increments, while replacement cables are often available only in full one-foot increments. Therefore, it is recommended to measure the cable tip-to-tip and round up to the nearest foot when selecting a replacement.

Additionally, when installing a new throttle control, you will need to take three specific measurements to ensure you get the correct length for the control cables. The first measurement is from the control, back along the gunnel, to the point where the gunnel and the transom meet. The second measurement is from the intersection of the gunnel and the transom to the centreline of the engine. The third and final measurement is from the centreline of the engine to the throttle attachment point. For outboard applications, it is important to add four feet to these dimensions to allow for adequate cable length for the engine to move back and forth.

By following these guidelines and considering the type of engine, control head, and cable length, you can choose the correct replacement cable for your Yamaha boat's throttle cable.

Installing the new Yamaha throttle cable

Before starting, ensure you have the correct length of the throttle cable. This is critical when replacing the cable. The length is normally stamped on the jacket of the cable, usually on the helm end. If you can't find the size, measure the old cable from tip to tip.

Now, follow these steps to install the new Yamaha throttle cable:

• Route the new throttle cable through the grommet in the lower motor cover. Apply soapy water to the cable and the inside surfaces of the grommet to ease the process.
• Place the throttle cable in position and use the Ball Socket Installer tool to snap the throttle cable connector onto the throttle lever.
• Place the throttle cable in the upper anchor pocket. Install a new cable retainer on the anchor block.
• Hold the twist grip in the full SLOW position and pull firmly on the cable to remove any backlash.
• Adjust the cable anchor so that the throttle cam is against the idle stop when the throttle cable anchor aligns with the mounting hole in the throttle body.
• Rotate the anchor four turns toward the end of the cable.
• Install the washer, cable anchor, and cable anchor screw on the throttle body. Tighten the screw securely.
• Rotate the twist grip to ensure the throttle cam goes to full throttle without bending the cable, and that it still returns to the IDLE stop.

By following these steps, you will have successfully installed the new Yamaha throttle cable, ensuring smooth and responsive throttle control for your boat.

Adjusting the new cable

Now that you've installed your new Yamaha throttle cable, it's time to adjust it for optimal performance. Here's a step-by-step guide on how to do it:

Route the cable: Start by routing the throttle cable through the grommet in the lower motor cover. This will ensure the cable is in the correct position.

Apply lubrication: Apply a small amount of soapy water to the cable and the inside surfaces of the grommet. This will help the cable move smoothly and reduce friction.

Connect the cable: Use the Ball Socket Installer tool to snap the throttle cable connector onto the throttle lever. This will secure the cable in place.

Position the cable: Place the throttle cable in the upper anchor pocket. This will keep the cable in the correct position and allow for smooth operation.

Install the cable retainer: Install the cable retainer on the anchor block. This will help keep the cable securely in place.

Test the throttle: Hold the twist grip in the full slow position and pull firmly on the cable to remove any backlash. This will ensure that the throttle responds correctly when you increase or decrease the speed.

Adjust the cable anchor: Adjust the cable anchor so that the throttle cam is against the idle stop when the throttle cable anchor aligns with the mounting hole in the throttle body. This will ensure that the throttle has the correct amount of tension.

Rotate the anchor: Rotate the anchor four turns toward the end of the cable. This will fine-tune the throttle response.

Install the washer and screw: Install the washer, cable anchor, and cable anchor screw on the throttle body. Tighten the screw securely to hold the cable in place.

Test the throttle range: Rotate the twist grip to make sure the throttle cam goes to full throttle without bending the cable and still returns to the idle stop. This will ensure that the throttle has a full range of motion.

Check for smooth operation: Finally, check that the throttle operates smoothly and responds correctly to your input. Make any necessary adjustments to ensure optimal performance.

By following these steps, you'll be able to adjust your new Yamaha throttle cable for safe and efficient operation. Remember always to refer to your Yamaha owner's manual for specific instructions and safety precautions.

Maintenance and care of Yamaha throttle cables

Checking for Wear and Tear

Firstly, it is important to regularly inspect your Yamaha throttle cable for any signs of damage. The throttle cable is a critical component of your boat's function and should not be overlooked. Visually inspect the cable for cracks, kinks, corrosion, or severe wear and tear. This can be done by systematically checking the cable from the throttle grip to the throttle body/carburetor.

Testing Throttle Operation

After each race or every 2.5 hours of operation, it is recommended to check the throttle operation. Poor full throttle performance may indicate that the throttle cable has too much slack, while an engine that is difficult to control or has an erratic idle may suggest insufficient throttle cable slack.

Measuring Throttle Cable Free Play

To measure throttle cable free play, mark the grip in relation to a reference point, such as the split in the throttle cable housing. Twist the throttle until resistance is felt, then measure the movement. Most makes/models specify 2-3mm of throttle grip free play.

Checking Throttle Return

All throttle systems are designed to fail closed if the throttle cables break or the rider loses control. To check throttle return, fully open the throttle and let go, ensuring that the throttle returns to the closed position quickly and easily. Check with the handlebars in various positions, including all the way to the left, centered, to the right, and halfway between center and full stop on each side. If the throttle does not return properly, the cable may be binding, incorrectly routed, frayed, or corroded.

Adjusting Throttle Cables

If your Yamaha boat has dual throttle cables, you will need to identify the accelerator and decelerator cables. The accelerator cable is put under tension when the throttle is opened, while the decelerator cable is under tension when the throttle is closed. Loosen the locknuts and turn the cable adjusters to slacken or tension the cables. The decelerator cable tension is usually set so that there is no play when the throttle grip is completely closed, followed by the adjustment of the accelerator cable.

For single throttle cable adjustment, simply remove any dust covers protecting the cable adjuster, loosen the locknut, and adjust the cable adjuster to achieve the correct amount of free play, typically 2-3mm.

Replacing Throttle Cables

When replacing Yamaha throttle cables, it is important to select high-quality cables that meet OEM specifications. Cables should be pre-lubricated and made with nylon inner sleeves, tightly-wound steel inner cables, and a flexible PVC outer jacket for smooth operation and longevity.

To replace the cables, start by loosening the throttle cable adjusters and slackening the cables. Remove the fasteners holding the throttle cable housing together, then remove the cable ends from the housing pulley, taking note of the accelerator and decelerator cable positions.

Remove any necessary covers from the throttle body or carburetor to access the cable ends. Loosen the lock nuts and adjusters, then carefully remove the cable ends from the pulley. Prepare the new cables by applying cable lube to both ends and checking their smoothness by moving them back and forth.

Finally, route the new cables in the same way as the old ones, ensuring you follow the OEM routing. Reinstall any components that were removed to access the cable system, then test the functionality of the new cables with the engine off and then with the engine idling.

Frequently asked questions