How To Fix Gas Leaking From Lawn Mower Air Filter?

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A lawn mower, when in one place, is a boon for the lawn owner to keep their garden healthy; it is equally annoying when anything goes wrong. Everyone who uses a lawn mower will agree with us over here.

Though many issues arise with mowers when not kept well, the most dangerous one is a hot mower leaking gas. The mower, when leaking gas, is fatal if you keep it in a garage attached to your residence.

If you face such an issue, you must address it as soon as possible. Delaying such kind of issue can turn into an accident.

In this article, we will tell you the reasons why your lawn mower must be leaking gas. We will also discuss the best ways to fix a gas leaking from the lawn mower air filter. Without missing a fraction of a second, let’s solve the issue first.

The Most General Reasons Why Gas Leaks From The Air Filter

The Most General Reasons Why Gas Leaks From The Air Filter
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Gas leaking out of the lawnmower engine might be the consequence of a small mistake, such as tilting it to the wrong side, even though it could appear spectacular at the moment. Even if the carburetor has a problem, it is usually relatively simple to remedy.

The most probable reasons your lawn mower leaks gas are:

  • A leaky gas faucet.
  • An obstruction choking.
  • Worn float needle in the carburetor.
  • The lawnmower spun to the wrong side.
  • The gas bowl seal on the carburetor has deteriorated.

Let’s talk about these reasons in a more elaborated manner for your better understanding.

1. A Leaky Gas Faucet

A Leaky Gas Faucet
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The gas tap is fixed between the carburetor and the gas tank. When turned off, it has the function of stopping gas flow between the tank and the carburetor.

These, made up of frequently plastic components, deteriorate after a few seasons and eventually stop working.

2. An Obstruction Choking

An Obstruction Choking
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The choke fixed in the lawnmower body enriches the gas/air vapor enabling the cold lawnmower to start.

If this choke gets obstructed, its cooling function of it gets compromised. Therefore turns into the situation o are facing right now.

3. Worn Float Needle in the Carburetor

Worn Float Needle in the Carburetor
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In the lawn mower, a carburetor fuel supply includes a fuel bowl, float, and needle. As you must have understood from the word float, it is a float, and it is attached to a needle with a rubber tip.

This float’s job is to raise the needle when the fuel level rises. The needle opposite the fuel supply port will be shut once the fuel bowl is filled.

When the rubber needle seal deteriorates, failure frequently happens in the carburetor.

As a result, fuel keeps filling the carburetor and finally goes into the housing for the air filter; flooding your air filter and wearing it causes the needle’s seal-tipped tip to become pink. The seal is included in the carburetor needle seat on some engines.

Also Read: How To Make A Riding Lawn Mower Go Faster? (7 Possible Ways)

4. The Gas Bowl Seal on the Carburetor has Deteriorated

The Gas Bowl Seal on the Carburetor has Deteriorated
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The carburetor bowl seal is installed right in the middle of the carburetor bowl and the carburetor itself. Fuel will leak out if the nut holding the bowl is too tight, or the seal is installed improperly.

The rubber eventually fails because of its natural deterioration over time. Any fuel leaking will go into the air filter, becoming saturated and leaking on the ground. It happens when the air filter is attached to the carburetor.

Ways to Fix Gas Leaking From Lawn Mower Air Filter

Ways To Fix Gas Leaking From Lawn Mower Air Filter
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Gas leaking out of the lawn mower’s air filter is a serious problem that must be eradicated before it takes shape and becomes a giant problem.

Tilt Mower in a Correct Way

Ways you can tilt the mower in the correct way for fixing gas leaking from the lawnmower air filter.

Tip Your Mower Over

With the handlebars pointing down, you can tip the lawnmower up most effectively. If you find this impossible, you may always tip the mower over with the carburetor side facing up.

Locate the Carburetor

The expected location for the carburetor is the face opposite the muffler. It includes an air-filter cover in usual rectangular or square and is made from plastic.

Disable the Engine

Before fixing the mower, the main thing to keep in mind is to switch it off. Turn off the gas and remove the plug wire. Turn your mower around, so the carburetor side is up since not all lawnmowers have a gas valve.

Though the wrong tilt of the mower is not the sole reason behind the hot gas coming out of the lawnmower’s air filter are other factors involved, which we will discuss further.

Fixing The Worn Float Needle in The Carburetor

Fixing The Worn Float Needle In The Carburettor
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The worn float needle in the carburetor is sending you the signal that it is now getting tired. When this happens, you have the option to replace the seal only. But if you ask us, we suggest you replace it all; the complete carburetor. These are inexpensive, and the repair is wholesome.

1. When the Needle is Down

The gas should flow continuously if the float shows dropped position.

2. When the Needle is up

By taking out the fuel bowl and raising the float, the gas should stop flowing, allowing you to examine the float and needle. Replace the needle/seal or the entire carburetor if it doesn’t.

3. Look Into the Choke Type

A lever on a lawnmower regulates the choke. The mower will flood with gasoline if a choke plate is stuck. Don’t rev the engine, as it worsens the problem.

Choke cables will occasionally require to be adjusted. But it is effortless to deal with it. As the engine heats, a thermostat next to the muffler gradually opens the choke plate.

The technique is an outstanding concept because it eliminates the need to fiddle with choke levers or priming bulbs. A choke that isn’t opening when the engine heats up may flood the engine with gas, since thermostats might malfunction occasionally.

Deal With the Gas Bowl and Fix its Malfunctioning

As we discussed above, every carburetor has one fuel bowl. It is where the fuel gets the pass into the carburetor. It’s from here only where the jet sucks the gas to feed the engine.

You can locate it at the back of the air filter in a bowl-like shape. Often, one bolt secures the bowl to the carburetor. Both the bowl-holding bolt and the gasoline bowl will have seals made of big rubber O-rings.

The seals might become squeezed when the fuel bowl is reinstalled and deteriorate over time. Both seals will get distorted and leak if the retaining bolt is tightened. Hence, while resetting the gas bowl, take special care.

Finally, Check The Gas Lines

The connecting clamp on the fuel line often leaks. In rare cases, the gas line goes through a rupture. Hence, just changing the connecting clamp can fix the issue.


When you observe a gas leak in the tank, fix it immediately. You can outsource the help, but if you want to do it yourself, the following are the tools you will need in the procedure:

  • Screwdriver or nut driver to remove the engine house.
  • Pliers to unclamp and reclamp the gasoline line’s squeeze clamps.
  • You will need a small dish or basin, to catch any gasoline that may spill from the fuel line.

Related FAQ’s

Why is the lawnmower leaking oil from the air filter?

The most probable reason for leaking oil from the air is the excess filling of oil in the oil, but it can also happen if the mower has been turned on its side.

Why is the lawnmower leaking gas from the primer bulb?

The primer bulb may be broken or cracked already. Or, mouses have made the defect by eating it. In that case, a gas leak can occur. If that is the case, replace the priming bulb and remove the retaining ring.

Can one clean a lawn mower soaked in oil?

To clean a lawn mower soaked in oil, you must remove and replace 95% of it with new oil.

How Do You Clean a Gas Soaked Air Filter?

Start by removing the air filter from the car to clean it. Place the filter in a well-ventilated place and give it time to dry. After the filter has dried, dispose of it by local laws.

What is the best solution to Soak Lawn Mower Air Filter In?

Soaking a lawn mower air filter in a solution of dish soap and warm water is the best method to clean it. After soaking the filter for at least 15 minutes, rinse it with fresh water.


The reason behind the gas leak from the air filter can be as minor as tilting the lawnmower on the wrong side. Or, it can be because of the issue inside the carburetor, which needs a sudden address.

The most harmful impact of this gas leak can be lawnmower gas combined with the oil in the piston chamber, which dilutes the oil and reduces its efficacy. It could cause fire danger, which should be avoided at all costs.

Go through the above discussion and find the most probable reason for the gas leak. Follow the instructions to fix the issue and continue with your lawn mowing.

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