Common Fixes When Your Motorcycle Has a Fuel Leak
Riding a motorcycle, especially an older bike, can often mean doing a fair amount of maintenance. And one of the more common issues motorcycle riders may encounter is a fuel leak. While it’s a problem that should be dealt with immediately, motorcycle enthusiast Matthew Bochnak says that a few simple DIY tips can help you identify the problem and repair it successfully.
Hey what’s up everyone, it’s Matt from HowToMotorcycleRepair.com. In today’s video, I want to show you common fuel leaks that may develop on motorcycles. Fuel leaks are very unsafe and dangerous, so if you walk out to your motorcycle and smell or see gasoline, do not attempt to start or ride the motorcycle. If you are riding your motorcycle and notice a fuel leak, park the motorcycle immediately!
Turn the fuel shut off valve to the off position and make sure the area is well ventilated. There should be no ignition sources or open flames in the area. Wipe up any fuel with rags, and lay them outside to dry so the fuel can evaporate. Once dry, place them in a sealed container and dispose of them properly.
Before we begin discussing these repairs, I do want to mention that if you are unsure or uncomfortable with anything mentioned in this video, please seek professional help and have it repaired properly. Now if you are going to tackle this yourself, make sure you are wearing the proper safety equipment. I always wear safety glasses and gloves. Make sure to have a fire extinguisher nearby especially when fuel is involved. It is also a good idea to have the service manual for your model so you can look up certain specifications. Do not begin any work until the engine and exhaust are at room temperature.
One source of a fuel leak may be from the fuel lines. Repairing fuel lines is an easy repair that any DIY’er can tackle. Fuel lines can become brittle, and may crack over time. Go ahead and bend a section of the line to see if the material is still pliable, and visually inspect them for cracks. If the fuel lines seem questionable, it would be a good idea to replace them. To remove fuel lines, make sure the shut off valve is in the OFF position, remove any clamps, and pull the lines off with your fingers or a set of pliers.
As for replacements, make sure you use hose that is rated for fuel, and is also the correct size. Many motorcycles will use metric sizes, so you may need to head over to your nearest motorcycle dealer for replacements. Here is a quick tip, use the old line to measure cutting your new lines. Also, replace the fuel lines one at a time if you have multiple lines. That way, the right connections will be maintained. Make sure to reinstall hose clamps at all connections.
Similar to fuel lines, gaskets in the fuel system become brittle and may crack over time. In my experience, the most common gasket to fail is the carburetor float bowl gasket. Replacing this gasket will require an intermediate skill level. You can spot this leak by looking at where the carburetor and float bowl meet. To replace this gasket, go ahead and drain fuel from the carburetor. Next, remove the carburetor. Carburetors have very small parts inside, so it is always a good idea to start with a clean and well lit work area. I like to use magnetic parts trays to hold all the small parts and fasteners.
Disassemble the float bowl, which usually is held on with 2 to 4 screws. With the float bowl removed, inspect the gasket. Use a pick to help remove the gasket. Here is a quick tip, apply a few small dabs of grease into the groove in which the gasket lies in. This will temporarily hold the new gasket in place during assembly. Go ahead and install a new gasket. Make sure to wipe up any excess grease. Reinstall the float bowl and tighten the screws. Reinstall the carburetor and check to see if your leak is gone.
Now let’s move on to the most common cause of fuel leaks, and it’s due to this little part right here, the float needle. It is common knowledge how problematic this part is, and requires an intermediate skill level to repair. This float needle regulates flow of fuel into the float bowl. When the bowl is empty or low on fuel, the float drops down and will open the needle valve so more fuel can enter. As the bowl fills up, the float will lift up and the needle will shut off fuel flow. Since the needle is a moving part, it often becomes worn and can no longer seal and stop fuel flow.
When the needle is worn, fuel continues to flow and it will either start pouring out the carburetor overflow and onto the ground, or it may fill the engine and airbox with fuel. To fix this problem, remove the float pin and float. Install a brand new float needle. Reinstall the float and pin. If the engine or airbox became soaked with fuel, make sure to check the condition of the air filter and make sure to change your engine oil.
Alright, well I hope you enjoyed that video. If you’d like to see more of my videos, head over to how to motorcycle repair dot com, or check out my YouTube channel MatthewMCrepair. I’m also on Facebook and Twitter. Just remember if you are unsure of anything discussed in this video, seek professional help. Thanks for watching and see you in the next video.