Gasoline-powered walk-behind and riding lawn mowers usually come with a fuel valve or shutoff switch to help them operate efficiently. If you own a lawn mower that uses gasoline to power its engine, the valve or switch is located along the fuel line.
The fuel valve or shutoff switch is one of the most important components in the operation of your lawn care equipment. To be precise, the switch or valve functions to prevent gasoline from leaving the fuel tank to the carburetor.
In most cases, if your mower model has a fuel valve, it is usually located at the base of the fuel tank where the fuel line connects to the fuel tank.
What is Fuel Valve in Lawn Mower?
The fuel valve, also known as the shutoff switch, gas valve, gas tap, petrol valve, or fuel flow valve, is a vital component of a lawn mower. Particularly, the fuel valve comes with gas-powered walk-behind and riding lawn mowers.
Its function is to stop gasoline from the fuel tank from flowing through the fuel line to the mower’s engine. Depending on the model of your lawn mower, you can cut off the fuel flow by turning on the shutoff a half-turn or a full turn. In some cases, you will have to turn the shutoff multiple full turns before blocking the fuel flow.
The fuel valve is one of a kind safety feature in a lawn mower. In this case, ensure that you close the fuel valve whenever you are making repairs to your engine. Besides, you should close the fuel shutoff if you are planning to store your mower over long periods before using it.
Where is The Fuel Valve On a Lawn Mower?
In most walk-behind and riding lawn mowers, the fuel valve or shutoff switch is usually located at the base of the fuel tank, where the fuel line connects to the tank. For the Honda lawn mower, the shutoff fuel valve is located below the gas filler cap beside the air filter cover.
Where Is The Fuel Shut-Off Valve Located?
The fuel shutoff valve in most walk-behind and riding lawn mowers is fitted below the fuel tank where the fuel line connects to the tank. If you own a Honda walk-behind lawn mower, you will find the fuel valve below the gas filler cap beside the air filter cover.
How Do You Open The Gas Valve On A Lawn Mower?
On one hand, you need to turn on the fuel valve when using your lawn mower. Remember that the fuel valve connects to the mower’s fuel tank and as such facilitates gas flow. Also, gasoline-powered mowers require sufficient fuel and air for the combustion process to be a success. As such, the fuel valve should be on when the mower is in use.
On the other hand, you should turn off the fuel valve when you are done mowing your lawn. In other words, the fuel valve should be off whenever the lawn mower is not in use.
But how do you turn the fuel shutoff valve on and off? In most cases, the fuel shutoff valve is tap-like and you can simply turn it. If you own a Honda walk-behind lawn mower, turn counterclockwise for on and clockwise for off.
Should The Fuel Valve Be On Or Off?
You just finished mowing using your gas-powered lawn mower and you are taking some fresh air before starting on the next job but did you remember to shut off the fuel valve? In this section, you’ll get all the information you need on whether the fuel valve should be on or off.
Most small engines like those in lawn mowers have a fuel valve that should be turned off whenever the engine is not in use.
You can easily forget to shut off the fuel valve – it happens quite often than it should. Precisely, you should pay more attention when working between jobs since it is easy to forget.
Fuel shutoff is very important, especially when moving a gas-powered lawn mower because slight vibrations can cause the fuel to flow into the carburetor, the float chamber, and into the intake valves – this can potentially damage your lawn mower.
As such, when you finish using your lawn mower, shut off your fuel valve.
Fuel shutoff is very important because it helps prevent:
- Engine Flood
Let’s first start by understanding how the float works. In a lawn mower, the float chamber is usually located below the carburetor body. The function of the float chamber is to maintain a constant fuel level during engine operation.
It does this through the operation of the float and the needle valve. Remember that the fuel flows from the fuel tank, to the fuel valve, and into the float chamber through the needle valve. This fuel intake causes the fuel to rise, and in turn, when the fuel rises to a specific level, the float also rises.
Immediately the fuel pressure balances with the buoyancy of the float, and the needle valve shuts off preventing further fuel from passing. This system of operation helps maintain the fuel at a predetermined level.
Now, when you forget to turn off the fuel valve, it can potentially cause the mower’s engine to flood. Vibrations cause the carburetor float to drop in the float chamber. Low float equals reduced pressure against the needle valve. As a result, pressurized fuel from the fuel tank flows through the needle valve.
If this occurs more often, fuel will overfill the carburetor and flow into the cylinder. Fuel in the cylinder can flood the combustion chamber and prevent the engine from turning.
- Hydraulic Lock
In case you forget to turn off the fuel valve and the needle valve allows fuel into the float chamber more often. The fuel will overflow the fuel chamber, flood from the carburetor’s throat, and flow into the cylinder. Fuel in the cylinder can potentially flood the combustion chamber above the piston thus creating a hydraulic lock. In this case, the mower’s engine will not start.
In severe cases, the fuel can drain past the piston rings and dilute the mower’s oil in the crankcase. This can damage the engine. Even with diluted oil, you might be lucky to start your mower but severe and premature engine damage will follow.
Where is The Fuel Valve On a Honda Lawn Mower?
Note that not all lawn mowers are fitted with a fuel valve however; all Honda mowers come with it. If you are new to lawn care or it is your first time using a Honda lawn mower, you might be wondering where the fuel valve is located. For Honda-walk behind mowers, the fuel shutoff valve is located below the gas filler cap beside the machine’s air filter cover.
It is tap-like and all you need to do is turn it on or off. To turn the fuel shutoff valve on, turn it counterclockwise. On the other hand, turn it clockwise for off. Remember that when left unused over long periods; they can become stiff making it hard to turn either way.
Most lawn mowers come fitted with a fuel valve that should be shut off whenever the engine is not in use. Fuel shutoff is important especially when moving equipment since vibrations can cause pressure imbalance, therefore, causing the needle valve to allow fuel to flood the carburetor, flow into the float chamber, and down through the intake valve.