Whether you’re using a single-stage or dual-stage gas-powered snowblower to clear the snow drifts from a walkway, driveway, or street, you need the equipment to run dependably and not leave you out in the cold struggling to keep that snow thrower operating. That’s why it can be so alarming to discover that gas is leaking from your snowblower… and frustrating when you realize you don’t know where the leak is coming from.
Repair Clinic has identified the eight most likely places that fuel leak may be originating from and the part or parts you can replace to fix the leak. Before we get to that, let’s examine the path the fuel takes through a gas-powered snowblower.
The path the fuel takes through a gas-powered snowblower
Most gas-powered snowblowers rely on a four-cycle engine to operate and, just like an automobile engine, a snowblower engine runs on gasoline and has a separate sump for oil.
Use gasoline with no more than 10% ethanol
While filling up the snow thrower’s fuel tank is the obvious first step, there are some good practices you should be aware of before you remove the gas tank cap to begin filling. Snowblower engines are designed to use gasoline with no more than 10% ethanol, so be careful with the kind of fuel you’re pouring into the tank. Gasoline with higher levels of ethanol can be corrosive and attract water, causing the engine to have starting or running problems. The high levels of ethanol can also damage the fuel system.
Fuel storage tips
You should store the gasoline in a clean, sealed plastic container approved for fuel storage. If equipped, keep the container’s vent closed when not in use and always store the container away from direct sunlight. If you anticipate storing the fuel for longer than three months, consider adding a fuel stabilizer when you fill the container.
The carburetor mixes fuel and air to run the engine
The fuel exits the snowblower’s gas tank through a fuel filter and flows through fuel lines past a fuel shut-off valve or fuel shut-off solenoid (depending on the engine type). The fuel may also be drawn through a fuel pump (again, depending on the engine type) and past a primer bulb before entering the engine’s carburetor. An intake valve opens as the engine piston travels down the cylinder, creating a vacuum which draws fuel and air through the carburetor where the two mix before entering the cylinder. The piston will travel back up to the top of the cylinder compressing the fuel and air mixture which is then ignited by the spark plug pushing the piston back down the cylinder. As the piston moves back up the cylinder an exhaust valve opens and the combustion gases will then exit through the muffler. This cycle repeats as long as the engine is running.
If your snowblower is leaking gas, it’s going to happen somewhere between the fuel leaving the gas tank and when it is drawn into the engine cylinder. Of course, you should first make sure there are no holes or cracks in the gas tank itself. Is the tank looking good? Okay, here are the eight most likely causes:
- Worn carburetor bowl gasket – If the leak appears to be coming from the carburetor, it’s likely the carburetor bowl gasket is worn out or missing. You should install a new gasket to provide a proper seal for the bowl.
- Defective float assembly – Various float assembly components inside the carburetor bowl could be defective as well. The float needle opens and closes the float valve to allow fuel to enter the bowl. If the float needle or the float itself is damaged, the carburetor may continue to fill with fuel until it overflows. You should be able to stop the leaking by replacing one or more of these components. If several float assembly components appear worn, consider purchasing a carburetor repair kit.
- Cracked carburetor – The leaking fuel could be coming from the carburetor itself. Over time, the carburetor can develop cracks due to the vibration and heat generated when the engine is running. If the carburetor shows any sign of damage, you will need to be replace it with a new one.
- Damaged fuel filter – It’s also possible that the leak is coming from a crack in the fuel filter housing. Inspect the fuel filter for any damage and replace if necessary.
- Leaking fuel line – One or more of the fuel lines may have developed a leak as well. While it may be tempting to try and repair the line or trim the damaged section then stretch the remaining line to fit onto the nearest valve, this practice will usually result in further damage or the outright failure of the line. It’s best to replace any damaged fuel line with a brand new one.
- Damaged fuel pump – A fuel leak could also be coming from a damaged fuel pump. Check the component for cracks or pinholes in the body and make sure the fuel lines and pulse line fit tightly on the fuel pump.
- Brittle primer bulb – The primer bulb draws fuel through the carburetor when pushed to prime the engine when first starting. Over time, the rubber can become brittle and crack causing the bulb to leak gas. Installing a new primer bulb will fix the problem.
- Broken fuel shut-off valve or solenoid – Finally, you should inspect the fuel shut-off valve or shut-off solenoid for leaks. You should also confirm the fuel shut-off lines fit tightly and are free of cracks or tiny holes.
Use only genuine OEM parts to fix that snowblower gas leak
If you need to replace a carburetor component, fuel line, fuel filter, fuel valve, or primer bulb to stop your snowblower from leaking, it’s important to use a genuine OEM part for the best results. Repair Clinic makes this easy by stocking only original manufacturer parts that match snowblowers manufactured by such industry leaders as Craftsman, Toro, Ariens, Honda, MTD, Troy-bilt, and Cub Cadet. You can find all the genuine manufacturer parts that fit your snow thrower by entering the full model number of the equipment in Repair Clinic’s “Search Parts Online & Get Answers” search bar. You can then identify the specific part you need by using the “Part Category” (example: “Hose, Tube & Fitting”) and “Part Title” (example: “Fuel Line”) navigation filters.
More than just a parts warehouse, Repair Clinic has all the repair resources you need to put you “in the know” when it comes to fixing your snowblower. Want to know how to correctly install a new gas tank on a model 38752 Toro snowblower? How about the proper procedure for replacing a carburetor on the model 31AM63TR756 Cub Cadet snow thrower? You can find model-specific videos, step-by-step guides, schematics, and more by entering the full model number of your snowblower or the snowblower’s engine in the Repair Clinic “Videos & Articles” search bar. As your repair partner, Repair Clinic has the parts and know-how to help you fix all of your lawn & garden equipment, home appliances, and heating and cooling units.