Mower Fuel Tap

First off they're not fitted to all mowers, so you might be looking for something you don't have. If your mower is a Honda or has a Honda engine fitted, it will certainly have a fuel tap.
So what is a mower fuel tap? A mower fuel tap is a valve, its function is to allow you control fuel supply to the carburetor by turning a tap on or off.

They're usually plastic but older mowers may have a metal tap fitted. A fuel tap is also known as a fuel valve, shut off valve, or gas tap. It's sometimes marked with an arrow to show gas flow direction.

Some larger mowers will have a fuel valve solenoid which automatically shuts off fuel when the engine is shut off. 

This post should have you covered on fuel tap location and use, if however you need video help, check out "Mower gas tap video". It walks you through the locating and using your mower gas tap. The video library has a ton of other useful mower repair videos too. 


Where is it?

First I should point out that not all mowers will have one fitted. Fuel valves are sometimes incorporated into the carburetor, but mostly they are somewhere along the fuel line. 


To find it, simply follow the fuel line from the bottom of the fuel tank all the way to the carburetor. A fuel tap will be in an accessible area along this fuel line (If fitted).


Mower Gas Solenoid


It's fitted between the gas tank and the carburetor, somewhere along the rubber fuel line.

The fuel valve isn't fitted to all mowers, and on others it may be incorporated into the carburetor.

Mower Fuel Tap


The gas valve seen here is made from plastic but some are made from metal. Others will be built into the carburetor.

What Is A Fuel Solenoid?

A fuel shut off solenoid is an electrical valve and it's fitted to some mowers. If fitted, it will be on the bottom of the fuel bowl and will have a wire connector fitted.


These are usually only fitted to lawn tractors and large engine walk behind mowers.

Mower Gas Solenoid

What's it do?

The fuel solenoid operates with the the ignition key.

Its job is to stop gas flow to the engine when you shut the mower off.

Mower Fuel solenoid


Fuel shut off solenoid lives at the bottom of the carburetor and has an electrical connector.

How to Use it?

It's a tap, you know what to do. Fuel on, is when the line of the tap is in line with the gas line. Fuel off is when the tap is perpendicular to the gas line.


Mower gas valve

Turn off

The gas valve seen here in the off position.

Some valves will have an on/off symbol.

Mower gas valve

Gas On

Gas seen here in the on position.

When to Use it?

The fuel tap is especially useful when transporting your mower over rough ground or by car from one location to another. The constant bumping around can cause the fuel to flood into the engine or out through the air filter. This usually floods the spark plug and results in a no start.



Turning the valve off before starting any maintenance jobs is just good practice and will prevent fuel spills. Cleaning, removing carburetors or just taking a fuel sample is so much easier with the valve.


In the workshop I use them all the time, especially when troubleshooting carburetor issues. When no fuel tap is fitted, I use a clamp to cut fuel supply.



Inspecting the drive axle, blade or cleaning the deck will require turning the mower over. Turning the valve off before turning the mower over will prevent fuel flooding the cylinder. 


When fuel floods the cylinder it can cause a few different problems:



Hydro-locking the engine - cylinder fills with gas which stops the engine cranking

Fuel can saturate the plug causing a no start

Fuel can spill onto the air filter preventing proper air flow

Fuel can seep into the crankcase causing a high oil level, and a smoky engine

Draining Gas

We've all been there - put bad gas, diesel, paint thinner ..... into the engine. The fuel valve makes draining the fuel tank hassle and mess free. Remove the gas line from the carburetor and place it into a container, turn on the valve. Easy right!



Winter Storage

The valve should be turned off when the mower isn't in use, this takes the load off the needle valve. Using a fuel stabilizer in the gas tank will leave you set for winter, and make easy work of recommissioning in the spring. 


Clean the deck and coat with WD40 or Teflon Non-Stick Lubricant - protects and repels grass, moisture and debris. 


When you need to inspect or clean your mower, if possible lift it from the front - Handle bars to the ground, if this isn't possible then always turn carburetor side up. 


Check out the complete guide "How to winterize your mower"




Transporting your mower by trailer can cause the carburetor to leak gas into the engine. When the gas fills the cylinder, it prevents the piston moving, a condition known as hydro-locking.


This happens because bumps in the road move the float needle out of it's seat, this allows gas fill the cylinder, wetting the plug and causing a no start.


Newer model ride-on engines have a fuel solenoid fitted which makes this condition less likely. Some models have a fuel pump fitted, these mowers are less likely to suffer from hydro-locking.



Can I Fit a Valve?

Yes, easiest job ever, fitting a fuel valve is simple. Order a fuel valve on-line, they're universal fit. 


Basically, two types - straight or elbow, and both are available in metal or plastic. Choose the one that suits you best, usually the plastic straight flow.


1 Tools

Tools needed are gloves, rags, knife or sharp pliers, cable ties or fuel line clamps.

gas line cut

2 Cut

Go ahead and cut your fuel line any where you have good access to work.

If you fuel line is bad, now's the time to take care of it.

fuel valve Fitting

3 Push On

Push the valve on to the fuel tank side of the cut fuel line first, and then put valve in the off position.
Ride-on mower valve

4 Zip

Finally fit your hose clamps or cable ties. I like cable ties - they're fast, but only single use.

 Now turn fuel on and check for leaks. Nice work!

Related Question

Are mower fuel taps universal? Yes, mower fuel taps are universal. Most mowers will use 1/4" id fuel line and the universal fuel tap is a push on fit.


Auto Technician and Writer at Lawnmowerfixed | Website

John Cunningham is an Automotive Technician and writer on I've been a mechanic for over twenty years, I use my knowledge and experience to write "How to" articles that help fellow gear-heads with all aspects of mechanical repairs, from lawn mowers to classic cars.