Mower carburetor leaking gas. Briggs And Stratton Leaking Gas Out Of Air Filter? (Fix It Now! )

Reasons A Generator Carburetor is Leaking Gas How to Fix

If you have smelled an odor of gasoline in your garage and followed your nose to your generator, you’ll likely see that the source of the leak is around the carburetor.

The generator is a contraption that can be intimidating to anyone who hasn’t disassembled and reassembled one. When I got into small engine repair about 7 years ago as a side hobby, I was so confused by the carburetor and what everything did on it.

As a general rule, a generator’s carburetor will leak gas due to an improper seal between the float needle and the seat, damaged gaskets around or under the carburetor bowl, or the bolt at the bottom of the bowl is not tightened properly.

  • Bowl Gasket is Cracked, Pinched, Split
  • Drain Screw Gasket is Cracked, or Not Tightened Properly
  • Bowl Bolt Gasket is Cracked, or Not Tightened Properly
  • Fuel lines are Cracked
  • Fuel shutoff solenoid is Leaking
  • Float needle not seating properly (Fuel Leaking out of the Air Filter or Fuel in your Oil)

I will guide you through the 6 primary reasons that you might be finding fuel leaking around your generator and what you can do to fix them.

Before you FOCUS all of your attention on the carburetor itself, dry everything with a rag first and verify that you do not have a leaky gas tank or a rotted fuel line at the gas tank. If this occurs, gas can run down the outside of the fuel line to the carburetor and throw you off course.

mower, carburetor, leaking, briggs

With that being said, let’s dive in!

⬇⬇⬇ Here’s a video I made to guide you through the common problem of why a carburetor leaks gas from the air filter (or throat of the carburetor) and how to fix it. I’ve had this happen to lots of small engines that I’ve repaired over the last 7 years. If your air filter smells of gas, or if your oil’s dipstick smells like gas, then this video is for you! ⬇⬇⬇

The black ring is the bowl gasket for the carburetor.

In either case, you will need to shut off the fuel shut off valve and find a suitable container to drain some fuel into. Grab a 10 mm wrench or socket and remove the main bolt which is located on the very bottom and center of the bowl.

With the bolt removed, gasoline will pour out until the bowl empties. It shouldn’t be much.

Once the gasoline is drained out, pull the bowl off and inspect the gasket. If it has any cracks, has dried out, is split, or has a permanent pinch in it then you will need to replace this gasket. Thankfully they’re not expensive. You might as well buy two while you’re at it and keep a spare one inside and out of the sun. My wrench is on the drain bolt. The bolt that holds the carburetor bowl in place is right behind it.

If you verified that the bolt is tightened properly, shut off the fuel valve, and place an appropriate container underneath the carburetor for catching gasoline. Use that 10 mm wrench or socket to remove the drain screw. Inspect the gasket which is usually made out of fibrous, cardboard-like material. Inspect it and make sure that it doesn’t have any tears. If it’s bad it will need to be replaced.

In a pinch, I’ve actually used a piece of a shoebox as a replacement on my snowblower (it happened to be the same relative thickness as the fiber washer/gasket. I just took the old one off, dried it, laid it on a shoebox lid, traced the outline and cut it out. This worked until I was able to get a replacement. Who knows how long it would have lasted.

You might also be able to use a plastic milk jug as your temporary replacement.

Bowl Bolt Gasket is Cracked or Not Tightened Properly

Drain bolt on the bottom, the bowl bolt is right above it. The gaskets are a pinkish red color,

This one is similar to the one above. First, verify that the bolt is indeed tightened properly with a 10 mm wrench or socket. If it’s snug and then turned about and 8th of a turn more and still leaking then you need to drain out the gasoline in the bowl by shutting off the fuel valve and then use a 10 mm socket or wrench to remove the bolt at the bottom of the bowl.

Once the bolt is pulled out the gasoline will flow through the bottom and the bowl will likely stay in place if it had a good seal.

Check the integrity of a gasket which is often made of fibrous cardboard-like material. If it’s torn then replace it. And like I mentioned in the above step, you can dry off the damaged gasket, lay it on a piece of similar thickness cardboard (or milk jug), trace it, and cut it out as a replacement.

It’s still in your best interest to replace it with a proper gasket when you’re able to but don’t let a small leak like that stop you from having power in an emergency. Remember, the gasoline in the bowl is not pressurized.

Fuel Lines are Cracked

Fuel lines will become dry rot with time. This is especially true if you use ethanol-based fuel and let it sit in storage. They will often crack at the points where they join up to something as that is where the fuel lines are stretched slightly.

Investigate for any cracks and if you see them I recommend replacing all of your fuel lines at once if you have the time for it. With one cracked, the others are sure to follow. Black fuel line running from the white gas tank to the carburetor behind the air filter assembly.

When doing this it’s probably easiest to drain out all of the fuel out of your tank if it hasn’t already leaked out already. You can use an inexpensive hand pump, like this one on Amazon, or simply open up the drain bolt on your carburetor and let the fuel run through the open fuel valve through the carburetor and into a container.

After that, remove the fuel lines from where they are connected with a flat head screwdriver and a pair of pliers if necessary. You can reuse all of the hose clamps that were on the fuel lines beforehand. Slide the hose clamp on the new fuel line first and move it up a few inches. Then press the fuel line onto the fuel stem, then use a pair of pliers to move the clamp back down and place it over where the fuel line connects to the stem to hold it in place.

Fuel Shut-off Solenoid is Leaking

If your generator is equipped with a carburetor that has a fuel shut-off solenoid, you might notice a gas leak at that location.

A fuel shutoff solenoid is attached to the bottom of the carburetor bowl and is activated by electricity passing through the wires which causes a magnet to retract a plug that blocks the fuel jet when the generator is running or go back in place with a spring when the engine is turned off.

This prevents after-firing if the generator were to be stopped abruptly under a heavy load. After-firing is caused when you abruptly stop an engine while under load and the crankshaft is still spinning (at 3,600 rpms and coasting to zero). This causes the combustion chamber to keep sucking in air and fuel at a Rapid rate for a few seconds but doesn’t ignite it with the spark plug since the engine is off. The unburnt air and fuel mix is exhausted and combusts on the hot metal of your exhaust which creates a loud bang.

Typically, a fuel shutoff solenoid leaks at the gasket that is between the bottom of the bowl and the solenoid itself. In this case, you can replace it with a new gasket. Less common is a solenoid that is leaking from the bottom. If this is the case, you will need to have it replaced. It simply unscrews with an appropriately sized wrench and screws back in after detaching the wire connection above the carburetor.

Float Needle Not Seating Properly (Fuel Leaking Out of the Air Filter Assembly or Fuel Mixed in with Oil)

If you notice gasoline coming out of your air filter assembly or if you notice that when you check your oil it gushes out and/or smells like gasoline, then you have a float needle in your carburetor that is not seating properly to prevent unwanted gasoline from entering the carburetor.

Like water, or any other liquid for that matter, gasoline will try to seek its own level. When you have a fuel tank that is above the carburetor then the carburetor is gravity fed. The purpose of the float in the carburetor bowl is to raise up as the gasoline pours in and then close a needle valve when the float (level of gas) reaches a certain point.

It’s the same concept as your toilet and is why the water tank above your toilet bowl doesn’t overflow as its being refilled after a flush.

If your float needle is not creating a perfect seal, then gasoline will continue to pour in. Since it will seek its own level (the level of the gas tank from which it came) it will fill the bowl of the carburetor completely. Then it will seep up the jets and orifices of the carburetor until it reaches the throat or venturi tube (where your choke and throttle butterfly valves are).

Once there, it will flow either out towards the air filter assembly or into your combustion chamber or both, depending on gravity and how level your generator is.

If gasoline enters the combustion chamber it will gradually seep past the rings on the piston and fall down into your crankcase where it will mix with your oil.

Robert lives in central Michigan and enjoys running, woodworking, and fixing up small engines.

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Briggs And Stratton Leaking Gas Out Of Air Filter? (Fix It Now!)

Briggs and Stratton power tools and lawnmowers are reliable, that is until gas leaks from the air filter. This can happen for several reasons, but it is generally due to a faulty carburetor. Whether it be the needle valves, carburetor, or fuel shutoff valves, let’s take a look at what you can do when gas leaks out of the air filter on your Briggs and Stratton.

Your trusted and reliable Briggs and Stratton engine is showing signs of trouble. You have noticed gas leaking around the air filter. You begin to wonder if it is time to replace that old engine with a new one.

mower, carburetor, leaking, briggs

Gas leaking around the air filter on a Briggs and Stratton engine is often a sign that the carburetor needs work or that the fuel shutoff valve is not closing properly. The carburetor’s problems can include issues with the float, the needle valves, or a bad float bowl seal.

You can remedy most of these issues with a local parts store trip and a little time. Let’s look at some of the most common problems that cause gas leaking around the carburetor or air filter. The fix for most of these problems takes a few simple steps.

Be Cautious Before Your Start

The gasoline in your Briggs and Stratton engine is highly flammable. All it takes is a spark to get a good fire going in a hurry. Taking a moment to keep yourself safe is always a good way to start any project.

Before you do anything else, unplug the wire from the spark plug. It is unlikely that the engine will start without a sharp tug on the starter rope, but some electric start can kick over without warning.

You should always work on gas-powered equipment in a well-ventilated area. The fumes from the gasoline are dangerous. If gasoline vapor concentration in the air gets to a certain point, almost any spark or flame will ignite the vapor.

The Most Seen Reason Gas Leaks Around the Air Filter on a Briggs and Stratton Engine

You are mowing along, and the lawnmower begins to bog down and then dies. The mower is obviously choked with grass clippings. The natural tendency is to tip the mower on its side and clear the blockage.

When you tip the mower on its side, gasoline can flow from the carburetor into the air filter. You have saturated the air filter on your Briggs and Stratton engine with gasoline. The liquid gasoline leaks out of the air filter housing and prevents your mower from starting.

The Fix in This Instance

It is never a good idea to tilt any Briggs and Stratton powered equipment on its side. You can spill grass and if the engine is hot, start a fire. The oil in the engine can run back up into the cylinder and foul the spark plugs.

The easiest fix for this problem is don’t tilt the mower. If you forget and find yourself with a Briggs and Stratton engine with a saturated air filter, you two choices. You can wait for the air filter to dry or replace the air filter and restart the engine

The Fuel Shut Off Valve that Won’t

Most newer Briggs and Stratton engines have a fuel shut off valve. The valve is in the gasoline line between the carburetor and the fuel tank. Briggs and Stratton recommend that you shut this valve to stop the engine. After a couple of seasons, these plastic valves may begin to leak.

Repairing a leaking fuel shutoff valve is relatively easy and straight forward.

Step 1 – Get the Parts

Visit your local Briggs and Stratton parts dealer and pick up a replacement. Be sure and take the model number and the serial number of your Briggs and Stratton engine with you to the parts dealer. Having these numbers will ensure that you get the correct part.

Step 2 – Gather your Tools

The tools you need will vary from model to model. In general, you will need the following at the minimum.

How-To fix a leaking Briggs carburetor: the complete guide

  • Screwdriver or nut driver to remove the engine housing.
  • A pair of pliers to remove and replace the squeeze clamps on the fuel line
  • You will need a small dish or bowl to catch the small amount of gasoline that may leak from the fuel line.

Step 3 – Empty the Fuel Tank

Emptying the fuel tank can be tricky. The safest way to empty the gas tank on a Briggs and Stratton engine is to start the engine and let it run. The gasoline will eventually be exhausted, and you will have a relatively dry gas tank.

Trying to drain the gas tank into another container can be dangerous. You aren’t saving anything. Once you pour the gasoline into an open container, don’t put the gasoline back into your Briggs and Stratton engine. It may be contaminated and do more damage to your Briggs and Stratton engine.

Step 4 – Remove the Fuel Shutoff Valve

The fuel shut off valve is held onto the fuel line by two small spring clamps on each side of the valve. Use your pliers to squeeze the ears on the clamp. Slide the clamp up the fuel line away from the fuel shutoff valve on your Briggs and Stratton engine.

Work the fuel line back and forth until you can pull the fuel line off the broken fuel shutoff valve.

Step 5 – Inspect the Fuel Lines

Now is a good time to look at the fuel lines. These short rubber tubing pieces can crack or otherwise deteriorate due to age, vibration, and the heat they endure close the Briggs and Stratton engine.

If the fuel line shows any sign of cracking or brittleness, you should replace both fuel lines to prevent future problems.

Step 6 – The Clamps, Replace or Re-use?

Your new Briggs and Stratton fuel shutoff valve probably came with new clamps. If so, remove the old clamps from the fuel lines and put the new clamps back on the fuel lines. The old clamps may have lost some of their tension and could be a leak problem

Step 7 – Install the New Fuel Shutoff Valve

Push the fuel lines back on the barbed fittings on the new fuel shutoff valve. Make sure you orient the valve properly so that it easy to access and operate with the engine cowling is replaced. Move the spring clamps back to their positions close to the fuel shutoff valve.

Step 8 – Give it Some Gas and Crank it Up

Refill the gas tank with fresh gas and open the fuel shutoff valve. Give the fuel a few seconds to fill the float bowl on the carburetor. Don’t forget to connect the spark plug wire back to the spark plug. Give the rope a pull, and you should be back on the road.

Other Problems That May Occur

Other problems with the carburetor on your Briggs and Stratton engine may cause gas leakage around the air filter. Gas leaking from the float bowl of your Briggs and Stratton engine carburetor is a more serious issue.

Float Bowl Problems

The float bowl on the carburetor may have a bad seal ring. If the seal ring on the float bowl is cracked or broken, gas leakage may occur. A bad seal ring is easily replaced on most Briggs and Stratton engines. However, a few Briggs and Stratton engines now have sealed carburetors that can’t be opened for maintenance or repair. The only recourse is to replace the entire carburetor.

Carburetor Float Issues

The float inside the carburetor bowl on your Briggs and Stratton engine can stick. A stuck float usually happens after the engine has been in storage. Gasoline left in the carburetor for long can cause a gummy residue.

This gummy residue can clog the ports and openings inside the carburetor. The needle valve may also stick, almost as glued to the needle valve seat.

If you suspect that the leak from your carburetor has a problem with the float or float bowl, you should consult with a trained Briggs and Stratton repair technician. Many new Briggs and Stratton carburetors require special tools to repair.

Keeping Your Briggs and Stratton Carburetor Healthy and Happy

A little preventive maintenance will keep your Briggs and Stratton engine running for many years. Making sure the carburetor is clean is a major concern. Never leave gas in the carburetor for more than a few weeks. When storing your mower, run the engine until you burn all the gas out of the carburetor.

I hope that this article has given you some help in diagnosing and repairing your Briggs and Stratton engine leaking around the air cleaner. Be careful and work safely.

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Dennis is a retired firefighter with an extensive background in construction, home improvement, and remodeling. He worked in the trades part-time while serving as an active firefighter. On his retirement, he started a remodeling and home repair business, which he ran for several years.

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Gas Coming Out Of My Lawn Mower Exhaust – What’s Wrong?

You were driving around the yard mowing the lawn and suddenly you see gas coming out of the exhaust. This could be a serious issue, especially if it catches a spark. We have researched this issue in-depth and found some simple DIY methods that can help you repair your lawn mower without having to take it to a mechanic.

Gas leaking in your lawn mower’s exhaust muffler could be a sign of any or a combination of the following issues in the carburetor:

Stuck/warped carburetor float

Rusty carburetor needle

Worn carburetor needle seat

A gas leak coming from the lawn mower exhaust is never fun, but it’s also not difficult to fix. Keep on reading to learn more about how to deal with a lawn mower exhaust leak.

Carburetor Issues That Cause Lawn Mower Exhaust To Leak Gas

Before you think of replacing your lawn mower‘s carburetor, it might help to understand the mechanisms behind a carburetor.

What Is A Carburetor?

A carburetor is a device that mixes fuel and air together to create an engine’s power. The gas mixture is then ignited by the spark plug to create the explosion needed for the engine to work.

Carburetors are very sensitive devices that require regular maintenance. They use a fine mesh screen called the “jet” to atomize gasoline into tiny droplets.

One of the most common causes of a carburetor malfunction is dirt. Dirt can clog the jets, restricting the amount of fuel that flows through.

If the mesh becomes clogged with dirt, the fuel will not be dispersed properly, and the air-to-fuel ratio can get out of whack. This will result in sluggish engine performance and inefficiency in terms of fuel consumption.

In some cases, a clogged carburetor that does not undergo periodic cleaning and maintenance may cause the engine to suffer permanent damage.

What Is A Carburetor Float?

A carburetor float regulates the amount of fuel that is supplied to the engine by opening or closing the throttle valve in the carburetor. The float is typically attached to a float lever which acts on the throttle valve in the carburetor.

A spring keeps the float closed. If the engine requires more fuel, the float is moved to open the throttle valve, allowing more fuel to enter the carburetor. If the engine needs less fuel, the float is moved to close the throttle valve, causing less fuel to enter the carburetor.

What Happens If Carburetor Float Is Stuck/Warped?

A carburetor float works in the same way as the float in your toilet flush system does. So just imagine what will happen to your toilet if the float is stuck in the open position.

Similarly, if the float in your carburetor is stuck, fuel will flow out of it. A worn float spring is most likely the culprit for this issue. The float spring allows the float to go up and down as the latter meters out the fuel to the engine.

On the other hand, the float pin is what holds the float spring, the float itself, and the carburetor together and is different from the carburetor needle.

Carburetor floats are usually made of plastic material that is heat resistant. If the float has no issues staying closed or open, then it’s most likely leaking fuel because it is warped or damaged.

Carburetor Needle And Seat: A Basic Valve

The carburetor needle is a part that regulates the flow of fuel. It is responsible for varying the amount of fuel entering the engine to match the needs of the engine.

It is essential to ensure that the needle seat and the needle are in place in order to maintain the functioning of your carburetor. A properly installed needle seat is vital for ensuring that the engine runs smoothly and efficiently.

If either the needle or needle seat becomes damaged or clogged, it may affect the fuel mixture, leading to fuel leaks and other issues like sputtering or engine misfiring.

The video below keeps this topic sweet and simple, so check it out.

How To Fix Fuel Leaking From Lawn Mower Exhaust

There’s nothing worse than finding that your lawn mower is leaking fuel in the spot where you least expect it: the muffler. However, you may be surprised to learn that there are a few easy ways to fix this problem before it gets really bad.

Here are the steps to follow to fix a leaking fuel in the lawn mower muffler:

Drain the oil

This is to prepare the lawn mower for the carburetor cleaner. Make sure to drain all of the oil from the mower as best as you can.

You should do this because if the oil is contaminated with dirt or metal shavings, chances are these particles could get stuck into the carburetor and aggravate the issue. So drain the oil as much as possible.

Apply carburetor cleaner

The second step is to use a carburetor cleaner. Carburetor cleaners usually consist of a solvent that dissolves and breaks the bond of the sticky, gooey deposits that can gum up and jam the float.

Carburetors are complex pieces of machinery. It is easy for dirt and metal shavings to find their way into the carburetor and clog it.

Run the lawn mower

Turn on the engine and let the lawn mower run until the carburetor cleaner has completely traversed every nook and cranny of the carburetor.

The video below shows every step in this process:

If after applying the carburetor cleaner the leak still does not stop, chances are there is some other blockage in the carburetor. In this case, you might want to remove the carburetor and check what is causing the problem.

Alternatively, you may also choose to have the entire carburetor assembly replaced if you find issues that are not related to clogging or rusting with any of its parts. This saves you time and is more cost-efficient than replacing defective parts.

How to Fix a Leaking Carburetor on a 625EX Briggs and Stratton

Can You Spray Carburetor Cleaner Directly Into The Lawn Mower Carburetor?

Lawn mowers have carburetors that require cleaning to make sure that they operate properly. Most of us think that we should only use liquid carburetor cleaners in the same way we change and refill engine oil during routine maintenance.

However, there is a better way to clean a carburetor that you may not be aware of, and this is to spray it directly into the carburetor with the engine running.

Can Brake Cleaners Be Used As Alternatives For Carburetor Cleaners?

A brake cleaner is the next best alternative to a carburetor cleaner, and it offers the same benefits.

A brake cleaner is used to restore the performance of the brakes on your car. The cleaner helps to clean the carbon deposits off your brakes, making them work better. This is the reason why brake cleaners are safe to use as an alternative in case carburetor cleaners are out of stock.

Is Alcohol Effective In Cleaning Carburetors?

Alcohol is used in a lot of different ways and is usually very effective at what it does. But cleaning your lawn mower carburetor with it is probably one of the worst things you can do to it. Alcohol can corrode some parts of your carburetor that are made of aluminum and zinc, so it’s best to avoid it.

Can You Use Vinegar In Cleaning Carburetors?

Most homeowners think of vinegar as a great way to clean a lot of things around the house. But vinegar contains a chemical called acetic acid, which can react with certain types of alloys and metals. The downside to using vinegar is that it has an acidic quality that makes it corrosive to metal.

Acetic acid can also cause rust to form on metal surfaces. This can leave rust marks not only on your lawn mower carburetor, but on your car, boat, and motorcycle.

Is It Safe To Leave Gas In Your Lawn Mower Over The Winter?

It’s a good idea to remove the fuel from your lawnmower during the winter months. Leaving the gas in the tank can lead to several problems, including a potential clogging in the carburetor and in the fuel filter when reusing the same fuel after winter.

Gasoline crystallizes at a certain temperature and these gas crystals could get into the fuel filter and clog it. In addition, gasoline is made up of many different chemical compounds.

It can break down over time. This leads to the formation of gummy residue, which coats the engine and creates a sticky mess. To avoid this problem, do not leave gasoline in a mower for extended periods of time.

How Long Should Gasoline Be Allowed To Sit In Lawn Mower Fuel Tank?

As mentioned above, gasoline can break down if left sitting in the gas tank for an extended period of time. That’s why it is recommended that gasoline should be changed every 30 days.

If you store your lawn mower in the garage, you can easily accomplish this by either emptying the tank or adding a stabilizing agent. A fuel stabilizer is a mixture of chemicals that can prolong the shelf life of gas by neutralizing harmful components.

In Closing

Leaks in lawn mowers come in many different ways. Gas leaking from your lawn mower’s exhaust muffler is usually a sign of a carburetor issue.

While you should always get a professional to do a thorough inspection of your lawn mower, most leaks can be easily fixed if you are willing to try. With a little patience and attention to detail, you can repair these issues before they become major problems.

How to Fix a Go-Kart Carburetor That Is Leaking Gas

Spotting a gas or fuel leak from a carburetor is a sight that no go-kart racer likes to see. While a leaking carburetor is relatively rare compared to other things that can go wrong with your go-kart, it’s something that you should definitely fix immediately. In this guide, I’ll be teaching you how to fix a go-kart carburetor that is leaking gas.

You’ll notice the gas flowing into the intake manifold or out of your carburetor. There are five common reasons for a go-kart carburetor leaking gas and you can repair it by fixing a stuck carburetor float, unclogging the jets, repairing the broken carburetor float bowl gasket, or fixing a loose or torn gas line connection.

Leaving your carburetor in a leaking state can cause further damage down the road and will also likely lead to erratic idling, delayed starting, stalling and even poor fuel economy.

How Does a Go-Kart Carburetor Work

Before we go through the potential issues that may affect your carburetor and how to fix them, it’s important that you understand how a go-kart carburetor works and what the internal components are. If you’re already familiar with this topic, feel free to skip to the next section of this guide.

A go-kart carburetor or carb is a mechanical device that is attached to the engine and mixes air and fuel into an optimal ratio before it’s pumped into the engine. It takes in filtered air from one valve and fuel from the other, in order to mix it.

An optimally configured carburetor will not only increase the engine performance but also increase your fuel economy. This mechanical device consists of several components that you need to be aware of, so that you’ll know which parts it may be affecting and need to be cleaned or replaced when fixing it.

Parts You’ll Need to Know

  • Fuel Inlet (fuel into carb)
  • Air Intake (air into carb)
  • Float Bowl
  • Float Bowl Drain Screw

List of Potential Carburetor Gas Leak Issues

Now that you understand how a carburetor works and what the most important parts are, it’s time to look at the potential issues for gas leak and how to fix them.

Stuck Carburetor Float

Relevant Parts

A stuck carburetor float is by far the most common reason why a carburetor can leak gas. While it mostly causes a delayed engine start or an engine stall, it can also lead to fuel leaks. When you open the go-kart carburetor and detach the float bowl, you’ll see that the float doesn’t move up or down easily.

If that’s the case, then your carburetor float is stuck and you’ll need to clean the entire carburetor and possibly replace the float valve needle. The float valve needle is located on top of the float valve and enables the float to move up and down. If the needle is stuck, that also means that the float won’t be able to move.

Thoroughly cleaning the carburetor float, float valve needle and float pin should allow the float to move freely again. If that isn’t the case, then you’ll need to see which of the three parts is defective and replace it accordingly.

There are a few things that you’ll need to check and do, in order to fix a stuck carburetor float. Below is a step-by-step guide for this.

Steps to fix a stuck float:

  • Remove the carburetor from your go-kart
  • Remove the float bowl from the carburetor
  • Test if the float is stuck or obstructed
  • Remove the float pin
  • Remove the float
  • Remove the float valve needle
  • Thoroughly clean float, float pin and float valve needle
  • Rebuild lower section of carburetor and test float mechanism
  • Reassemble the carburetor

Clogged Carburetor Jet

Another common issue that can cause a go-kart carburetor to leak gas is a clogged jet. There are two jets that you need to be aware of. After detaching the carburetor and opening it, you’ll be able to spot both of the jets easily.

The location of the main jet is inside the float bowl. It’s the larger of the two jets and is responsible for supplying the carburetor with the required fuel. You’ll be able to identify them easily as their made of brass. The main jets kick in when the throttle is activated (60 – 100% range).

The other jet is called the pilot jet and has the same function but activates when idling. You’ll need to make sure that both jets are not obstructed or clogged. You’ll need to remove them. Give both of the brass jets a thorough clean in an ultrasonic cleaner with a cleaner solution or vinegar. If you find that the jets are no longer good for use, then simply replace them.

Steps to fix clogged carburetor Jets:

  • Remove the carburetor from your go-kart
  • Remove the float bowl from the carburetor
  • Remove the pilot and main jet
  • Thoroughly clean jets and remove dirt and debris
  • Test if jets are unclogged
  • Reassemble pilot and main jet
  • Reassemble the carburetor
  • Information: How to Clean a Go-Kart Carburetor (Step-by-Step Guide)

Broken Carburetor Float Bowl Gasket

Relevant Parts

When you detach the float bowl from the carburetor, you’ll notice that there is a gasket or an o-ring wedged in between the two components. The float bowl gasket acts as a sealant, which prevents air or fuel to escape from the carburetor. There are many gaskets on a carburetor, but the most common gasket that can break is between the float bowl and carburetor.

Due to wear and tear, the float bowl gasket can break or crack making it no longer airtight. This means that gas may seep out the sides. You’ll be able to notice this if you see that the carburetor is leaking gas from the side, where the float bowl connects to the carburetor.

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Unfortunately, once a float bowl gasket is broken it can’t be fixed. The good news is that you can simply replace it with a new one, as they’re very affordable and easy to slot in.

Steps to fix a broken carburetor float bowl gasket:

  • Remove the carburetor from your go-kart
  • Remove the float bowl from the carburetor
  • Remove the float bowl gasket
  • Insert the new float bowl gasket
  • Reassemble the carburetor

Loose Fuel Line Connection

Relevant Parts

The first place you should look at if you have a gas leak are the fuel lines that are running into the carburetor. Regular wear can cause certain connections to loosen on the carburetor and the first point you should inspect is the fuel inlet.

The fuel line is connected to the fuel inlet of the carburetor, as it transports the fuel from the fuel tank into the carburetor. The fuel line is connected to the fuel inlet via a clamp. If the clamp comes loose you can sometimes see gas leaking out of the fuel line onto the carburetor. While it may look like the leak is coming from the carburetor, it may actually come from a loose fuel line connection instead.

If the clamp is worn, replace it with a new one. They are relatively inexpensive and can easily be replaced. If the clamp has eaten into the fuel line and the end of the fuel line is damaged, you can cut the damaged piece off or replace the fuel line entirely.

Steps to fix a loose fuel line connection

  • Inspect the fuel line connection
  • If the fuel line is loose, remove fuel line clamp
  • If the clamp is damaged, replace it with a new one
  • If the fuel line is damaged, cut off or replace it entirely
  • Reattached the fuel line to fuel inlet on the carburetor

Torn Gas Line

A torn fuel line can also cause the fuel to seep on to the carburetor, making it seem like the leak is from the carburetor itself. If you see that the leak it’s coming from the carburetor, check the fuel lines from the fuel tank into the fuel filter and the fuel line from the fuel filter to the fuel inlet on the carburetor.A tear in one of the fuel lines will be obvious and you’ll need to fix this by simply disconnecting the fuel line and replacing it with a new one. This should be a quick fix and will only take you a few minutes.

Steps to fix a torn fuel line

  • Inspect the fuel line between the fuel tank and fuel filter
  • Inspect the fuel line between the fuel filter and the fuel inlet
  • Remove the damaged fuel line
  • Replace it with a new fuel line
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