Changing Fuel Pumps: A Guide For Briggs And Stratton Engines

Changing a fuel pump in a Briggs and Stratton engine can be a complex process. The fuel pump is typically mounted in one of four places: on the carburetor, near the fuel tank, or between the tank and carburetor. Before attempting any repairs or replacements, it is important to refer to the Small Engine Manual for specific instructions. The process of changing a fuel pump involves turning off the fuel valve, stopping the flow of gas, removing the pump, inspecting and replacing damaged parts, and then installing a new fuel pump. It is crucial to take safety precautions when working with fuel and to contact a certified dealer if unsure about any steps.

When to replace a fuel pump

Knowing when to replace your fuel pump is essential for keeping your lawnmower or snow blower in good condition. Here are some signs and guidelines to help you determine when it's time to replace the fuel pump on your Briggs and Stratton engine:

• External Fuel Leak: If you notice fuel leakage around the pump or in the pulse line, it indicates that the pump is not functioning correctly, and you should consider replacing it.
• Damage to the Pump: Remove the pump and check for hairline cracks or other damage on its external surfaces. If the pump has a metal body and is damaged, it is best to discard and replace it.
• Difficult Engine Starting: If your engine is hard to start or frequently stalls, it could be due to a faulty fuel pump. However, other factors such as spark plugs, choke cable, or fuel filter could also be the cause, so it's essential to diagnose the issue correctly.
• Engine Performance: A faulty fuel pump may cause the engine to run unevenly or reduce its performance. If you notice a significant decrease in engine power or unusual behaviour, it could be a sign that the fuel pump needs replacement.
• Age and Usage: Fuel pumps have a limited lifespan, and their performance may deteriorate over time. If your fuel pump is several years old and has been in frequent use, it may be time to consider a replacement, especially if you have noticed any of the above issues.
• Manufacturer Recommendations: Refer to your Briggs and Stratton engine manual or contact an authorised dealer to get specific recommendations on fuel pump maintenance and replacement intervals for your particular model. They can provide valuable insights into when and how often the fuel pump should be replaced.

Remember, the fuel pump is a critical component of your engine, ensuring the proper flow of fuel. By paying attention to these signs and guidelines, you can make an informed decision about when to replace your fuel pump, helping to keep your equipment running smoothly and efficiently.

How to remove the old pump

To remove the old pump, start by turning off the fuel valve at the base of the tank where the fuel line is attached. If your fuel pump does not have a fuel valve, you will need to stop the flow of gas using a fuel line clamp.

Next, loosen the mounting screws and remove the pump from the mounting bracket or carburettor. Check the pump for hairline cracks and other damage on its external surfaces. If the pump is damaged and has a metal body, discard it and prepare to install a replacement fuel pump.

With the fuel valve closed or the line clamped, remove the mounting screws. Then, disconnect the fuel hoses using needle-nose pliers to loosen the clips. Remove the screws and disassemble the pump.

How to install a new pump

To install a new pump, you will need to follow the instructions provided by the manufacturer. However, here is a general step-by-step guide on how to install a new fuel pump for a Briggs and Stratton engine:

Firstly, place the diaphragm spring and then the cup over the centre of the pump chamber. Insert a valve spring as well. Secondly, install the diaphragm, gasket and cover, securing them with pump screws. Ensure you tighten the screws with a torque wrench.

Next, attach the pump to the carburettor or mounting bracket, using the pump mounting screws. Finally, run the engine after the new pump installation to verify that there are no leaks.

Please note that different pumps may have some variants in their part configuration, but the basic instructions outlined above should guide you through the installation process for a replacement fuel pump.

How to fix a fuel pump

To fix a fuel pump in a Briggs and Stratton engine, you must first identify the location of the fuel pump. Typically, it is mounted on the carburetor, near the fuel tank, or between the tank and carburetor.

Once located, follow these steps:

• Turn off the fuel valve at the base of the tank, where the fuel line is attached. If there is no fuel valve, use a fuel line clamp to stop the flow of gas.
• Loosen the mounting screws and carefully remove the pump from its mounting bracket or carburetor.
• Check the pump for any hairline cracks or other damage on its external surfaces. If the pump is damaged and has a metal body, discard it and perform a fuel pump replacement.
• With the fuel valve closed or the line clamped, remove the mounting screws.
• Disconnect the fuel hoses using needle-nose pliers to loosen the clips.
• Remove the screws and disassemble the pump.
• Inspect the body for cracks or any other signs of damage. Soak metal parts in an all-purpose parts cleaner for up to 15 minutes.
• Check the hoses for cracks, softening, or hardening. Replace any faulty or worn parts.
• Discard old gaskets, diaphragms, and springs. Replace them with parts from an original manufacturer's repair kit.

After completing these steps, you can proceed with the fuel pump replacement process, which involves reassembling the new or repaired pump and attaching it back to the engine.

Fuel pump maintenance

Checking and Maintaining the Fuel Pump:

• Locate the fuel pump: It is typically mounted on the carburetor, near the fuel tank, or between the tank and carburetor.
• Turn off the fuel valve at the base of the tank or use a fuel line clamp to stop the fuel flow.
• Loosen the mounting screws and remove the pump for inspection. Check for hairline cracks and other damage, especially if the pump has a metal body.
• If the pump is damaged, it may need to be replaced. Soak metal parts in an all-purpose parts cleaner for up to 15 minutes.
• Inspect the hoses for any signs of cracks, softening, or hardening. Replace any worn or faulty parts with original manufacturer's repair kit parts.

Replacing the Fuel Pump:

• Turn off the fuel valve or use a fuel line clamp to stop the fuel flow.
• Remove the mounting screws and disconnect the fuel hoses using needle-nose pliers.
• Discard old gaskets, diaphragms, and springs.
• Place the new diaphragm spring and cup over the center of the pump chamber, along with a valve spring.
• Install the diaphragm, gasket, and cover, securing them with pump screws. Tighten using a torque wrench.
• Attach the pump to the carburetor or mounting bracket using the pump mounting screws.
• Always run the engine after installing a new pump to verify there are no leaks.

Additional Tips:

• Refer to your Small Engine Manual for specific instructions and safety precautions.
• Consider using a fuel stabiliser to maintain fuel quality and prevent engine issues.
• Regularly check your fuel filter and replace it if it is clogged or damaged to ensure optimal engine performance.

Frequently asked questions