Lawn Mower Not Getting Gas to Carb? Fixes that Work

It’s frustrating to work with a lawn mower that is not getting gas to the carburetor. It may have a hard start, stall when running or fail to start completely. So, why is a lawn mower not getting gas to the carburetor?

An empty fuel tank, clogged fuel filters and fuel lines, bad fuel, plugged gas cap, and a stuck float or float needle are the main reasons why a lawn mower is not getting gas to the carburetor.

Why is my Lawn Mower Not Getting Gas to the Carburetor?

Based on expert observations and diagnosis, the following are reasons why a lawn mower is not getting gas to the carburetor and how to fix the problem.

1. Empty Fuel Tank

Do you have enough fuel in the tank? The first thing to do is to check the fuel tank to ensure it is having sufficient gas. The fuel tank needs to have at least some fuel to power the motor.

How to Fix

Refill the tank and try to restart your lawn mower. If the lawn mower starts and then dies, it may not be getting sufficient fuel in the carburetor.

2. Clogged Fuel Filters

Lawnmowers are fitted with fuel filters on the fuel lines to strain any dirt, sediments and other contaminants present in the fuel from entering the fuel system. Using dirty fuels for a long period of time can clog the fuel filters. Fuel cannot flow through clogged fuel filters to reach the carburetor.

How to Fix

Draining the fuel tank, replacing the filter and refilling with clean fresh fuel should be able to fix this problem.

3. Plugged Fuel Lines

Thick and sticky deposits left behind from using old fuel can clog the fuel lines and prevent the free flow of fuel to the carburetor. Check the fuel lines to find the clog, you have to check all the sections and unclog the blocked parts.

How to Fix

Run a carburetor cleaner through the fuel pipes to loosen and remove clogs along the line. Additionally, blow out the line with pressurized air to flush out the debris

Control the fuel flow from the tank using a shut-off valve located at the bottom of the mower’s gas tank when cleaning the fuel flow lines.

4. Old Fuel in the Tank

Running your lawn mower on old fuel can cause restrictions and prevent the gas from getting into the carburetor. When the fuel is stored for a long period of time, some ingredients evaporate leaving behind thick and sticky substances that end up clogging the filter, gas lines and carburetor fuel system.

Most fuel contains ethanol to make them environmentally friendly. However, ethanol naturally attracts moisture from the air which may result in water in the gas lawn mower tank.

How to Fix

Drain the old contaminated fuel from the lawn mower gas tank and refill it with fresh fuel. If intending to use the same fuel for over a month, use stabilizers to keep the gas fresh. It prevents the fuel from degrading.

5. Stuck Float or Float Needle

Fuel cannot get into the carburetor if the float or the float needle is stuck. The float needle plays an important role in regulating the amount of fuel flowing into the bowl.

How to Fix

This problem is temporarily fixed by tapping on the carburetor gently with a rubber mallet. Clean the carburetor and replace the float or float needle if the problem persists.

6. Clogged Gas Cap

The top of a gas cap has a tiny hole that allows air into the fuel tank so that the gas can flow into the carburetor. When this vent is plugged it creates a vacuum that prevents the fuel from flowing into the carburetor.

How to Fix

To diagnose this problem, try to run a lawn mower without a fuel cap. If the engine runs okay without the fuel cap and eventually stops with the cap, then the problem is with the cap. Remove dirt and other debris that may be clogging this vent.

Signs that a Lawn Mower is Not Getting Gas to Carb

There are several telltale signs that your mower is not getting fuel to the carb, they include:

Lawn Mower Experiencing a Hard Start

If your lawnmower is experiencing a hard start, it’s usually a result of a stuck float needle. A hard start happens when the carburetor is not receiving fuel flow as required. The float and float needle help to regulate the amount of fuel in the bowl. To fix this problem, you have to clean the carburetor and replace the float needle.

Lawn Mower Won’t Start Completely

If your lawn mower won’t start completely, there is usually a problem with the flow of fuel to the carburetor. It usually results from dirt and debris collecting and blocking the fuel transmission system and other components such as fuel filters, fuel pipes, stuck needle, carburetor bowls and the gas cap vent.

Check the filters, gas pipes, carburetor fuel system and gas cap to ensure they are not clogged by dirty or thick and sticky substances from old fuel. Wash the carburetor and fuel pipes with a carburetor cleaner to fix this problem. Replace fuel filters and float needle to get your lawn mower working again.

Lawn Mower Starts then Stalls when Running

If the fuel tank is filled up with fresh gas but your lawn mower starts and then stalls after a few seconds when accelerating, there is high chance that the vent on the fuel cap is clogged. It creates a vacuum that cut the pressure that is needed to push the fuel into the carburetor.

Check the gas cap vent to remove dust and other debris that may be plugged in. If it doesn’t work, you may be required to replace it with a new gas cap.

No Fuel Odor

If your lawn mower can’t start and at the same time you can’t sense any smell of fuel coming out of the motor, it simply means that the mower run out of gas. Check the fuel tank to see if it has fuel, and refill it with fresh gasoline if the tank is empty.

Use a check stick to determine the level of fuel in the gas tank. The check stick has two marks, the low and high-level marks. If the fuel is below the low-level mark, you simply need to refill your fuel tank. With an empty fuel tank, the carburetor won’t get fuel.

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