This is Where Your Bad Boy Mower is Leaking Gas: Solved!

You walk out to your garage to find it filled with the smell of gas fumes in the air from a leak on your lawn mower. Before you begin working on your mower, you must open your garage door to ventilate the area and remove the fumes. Working in an enclosed area with gas fumes can be extremely dangerous.

A Bad Boy Mower may begin leaking gas from the carburetor, fuel tank, fuel lines, fuel pump, fuel shut-off valve, and fuel filter. This can be the result of old fuel degrading fuel components or leaving behind a residue causing components to gum up and stick.

Components can also become dry and brittle with age causing them to leak.

Below you will find the most common areas a Bad Boy mower will develop a fuel leak. You need to find and repair a fuel leak because fuel can damage your lawn and using a lot of fuel is just a waste of money.

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Follow all safety instructions provided in your equipment operator’s manual before diagnosing, repairing, or operating. Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.

7 Places Your Bad Boy Lawn Mower is Leaking Gas

Mower Carburetor

A little gas is stored in your lawn mower after it leaves the fuel tank. Over time, the carburetor can become dirty and components can stick or the gasket between the bowl can become dry.

Carburetor Bowl Gasket

At the bottom of the carburetor, you will find the carburetor bowl. There is a gasket that looks like a rubber band placed between the bowl and the carburetor.

This gasket is known to dry out and lose its sealing capabilities because it is exposed to changes in extreme temperatures.

Because of its location near the engine, the gasket heats up when the mower is running and cools down when it is not. This stress on the gasket can cause it to fail which will result in fuel leaking from the carburetor. The gasket must be replaced when the gasket fails.

Replace the carburetor bowl gasket on your Bad Boy mower:

• Shut off the fuel supply using the fuel shut-off valve or crimp the fuel line.
• Wipe off the dirt around the carburetor so foreign material does not get into the carburetor.
• Remove the screw at the bottom of the carburetor and remove the bowl. Have a rag available to catch any fuel that remains in the bowl.
• Remove the old gasket.
• Replace the new gasket. Be careful not to get any carburetor cleaner or other material on the gasket.
• Reinstall the bowl and tighten the screw to hold the bowl and carburetor together.
• Wipe down the carburetor.

If the gasket around the bowl is not the area of your leak on the gasket or you have found your carburetor is still leaking, move on and check the float on your carburetor.

Stuck Float

Look for a leak near the air intake. A leak in this area may signify you have a stuck float. The float is the part in the carburetor that kind of acts like a gatekeeper. It determines when to allow fuel to flow into the carburetor and when to stop the flow.

Deposits left behind by old fuel can cause your float to stick. When this happens, the float can no longer regulate fuel flow into the carburetor. Fuel can continue to flow into the carburetor and overflow with fuel running out of the carburetor.

To determine the actual reason why your float is sticking, the carburetor will need to be taken apart. You may have to clean the carburetor and float or replace the float. You can find steps to clean your Bad Boy carburetor here.

Stuck Float Needle

You may find the float needle needs to be replaced while inspecting the float. The float needle works with the float to keep gas flowing into the carburetor bowl. If you find the needle sticks, you must replace them.

Sure, tapping the side of your carburetor a time or two with a rubber mallet may unstick your needle, but this is a temporary fix and you will have to replace it.

To order parts for your carburetor, you must have the engine model and spec to ensure you get the right parts. Again, you need the information from the engine housing and not the actual mower model and serial number.

Cracked or Soft Fuel Filter

The makeup of fuel can degrade and soften your fuel filter causing it to form leaks at the seams. It is best practice to replace your fuel filter annually to minimize the chances your fuel filter leaks because it has begun to break down.

Replace a fuel filter that has become soft or is cracked and leaking. Be careful to not break off the ends of the filter while removing it from the fuel lines as they may be soft. Install the new filter with the arrow on the side of the filter facing in the direction of the fuel flow.

Bad Fuel Pump

Old fuel sitting in your fuel pump can degrade the plastic housing causing the plastic to become soft and develop leaks at the seams. A vacuum fuel pump needs to be replaced when you notice it is leaking.

Failed Seams on the Fuel Tank

Your Bad Boy mower most likely uses a high-density polyethylene tank where the seams can fail over time causing a fuel leak. When this happens, you should replace your fuel tank.

Fuel Shut-Off Valve

Your Bad Boy lawn mower may or may not have a fuel shut-off valve. If it does, check the valve as shut-off valves are prone to leaking. It must be replaced if you find it is the cause of your fuel leak.

Old Fuel Lines

Fuel lines will become dry with age. That can result in cracking and leaking. The fuel lines may also have been punctured by the clamps used to secure the fuel line to the fuel components. These clamps can become loose or puncture the line causing a leak.

Replace any dry or cracked fuel lines found on your Bad Boy. This is also a good time to convert your clamps to a worm gear clamp if your mower came with pinch-style clamps. The worm gear clamps are less likely to cause leaking because they don’t actually pinch your lines.

Bad Fuel Cap Seal

The seal in your gas cap may have failed. When running your mower, gas sloshes around the tank and can leak around the cap when it isn’t sealing correctly. If you smell a fuel leak and have checked all the items above, it’s time to check the fuel cap seal.

You may have missed the wet spot that formed around the fuel cap because fuel will evaporate leaving no trace of a wet spot.

To check for a leak with your fuel cap installed, rock your mower back and forth to splash fuel up to the cap area. Watch for a wet spot to form indicating you need to replace your fuel cap