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HomeRepair HelpRepairLawn mower leaking gas Repair
Lawn mower leaking gas
If your lawn mower is leaking gas, start at the carburetor. In many cases, a lawn mower gas leak or gas leaking from the bottom of the lawn mower is caused by a dried-out or missing carburetor bowl gasket on the bottom of the carburetor. Next, check the float needle, since a worn or damaged needle can fail to shut off fuel and let the carburetor overflow. Another common cause of a mower leaking fuel is a bad carburetor gasket, especially when fuel is dripping from the bottom of the carburetor. After that, inspect the primer bulb for cracks or brittleness, because even a small split can cause a noticeable leak. If those parts look good, move on to the fuel shut-off solenoid and fuel lines for loose connections, cracks, or pinholes. A stuck carburetor float can also keep fuel flowing, in which case cleaning the carburetor may help, but you may need to rebuild or replace it. Whether you are fixing a Honda, Craftsman, Toro, Troy-Bilt, Husqvarna, Cub Cadet, or MTD mower, enter your model number on RepairClinic.com to find the exact replacement part for your machine.
01 - Carburetor Bowl Gasket
If the lawn mower leaks gas the carburetor bowl gasket on the bottom of the carburetor might be dried out or missing. If the leak is coming from the bottom of the carburetor, try replacing the carburetor bowl gasket.
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02 - Float Needle
The float needle might not be shutting off the fuel. The float needle opens and closes the float valve to allow fuel to enter the float bowl. If the float needle is damaged, the carburetor will continue to fill with fuel until it overflows. If the float needle is defective, replace it.
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03 - Primer Bulb
Over time, the rubber of the primer bulb can become brittle and cracked. If the primer bulb is leaking, replace it. Don't try to patch or repair it.
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04 - Carburetor Gasket
If fuel is leaking from the bottom of the carburetor, the carburetor gasket might be dried out or missing.
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05 - Fuel Shut-Off Solenoid
Check the fuel shut-off valve for leaks, and ensure that the fuel lines fit tightly on the valve. If the fuel shut-off solenoid is leaking, replace it. In addition, inspect the fuel shut off lines for cracks or tiny holes. If a fuel shut-off line is leaking, replace it.
Highly Likely
06 - Float Bowl Gasket
If fuel is leaking from the bottom of the carburetor, the float bowl gasket might be dried out or missing.
Highly Likely
07 - Float
The float might be stuck open. If the float is stuck open, remove the carburetor assembly from the engine and clean it thoroughly. If the cleaning the carburetor is not effective, either rebuild or replace the carburetor.
Highly Likely
Frequently Asked Questions
Why is my lawn mower leaking gas from the bottom of the carburetor?
Can a bad primer bulb cause a lawn mower gas leak?
What does it mean if my mower is leaking fuel when it is not running?
Should I clean the carburetor or replace parts if my lawn mower has a gas leak?
How do I find the right carburetor gasket, float needle, or primer bulb for my lawn mower?