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Should a lawn Mower fuel filter be full?

You should realize optimal performance with a good lawnmower from a reputed manufacturer like John Deere, Kohler, and Briggs& Stratton. Most importantly, knowing how every part of your machine functions will keep you in the know should there be faulty components. Let’s take, for example, the lawnmower fuel filter-which is the subject of this post. A filter purifies fuel before it goes into the combustion chamber. Thus, ensuring it is always in perfect health is crucial.

Should a lawn Mower fuel filter be full?

Yes, a lawnmower fuel filter should be full. Lack of enough fuel in the filter will hamper the performance and is bad for its health. Lawnmower filters that do not fill up with fuel often signal a problem.

A faulty filter has a direct impact on the functionality of your lawnmower. And it is always a case of dirt and impurities getting into the combustion chamber. Such is a problem that will render your machine less effective. Even worse, a decrease in performance due to clogged gas filters will result in engine ignition problems. As a result, homestead craftsmen do many other questions. For example, why is fuel not filling up my lawnmower filter? How do clean clogged lawn mower gas? Do I need to replace the filter with a new one?  How often should you clean the filter?

Why should a lawn mower fuel filter be full?

The next question which you are probably asking is why should the filter be full of gas? Well, when there isn’t enough fuel going through this component, your mowing tractor may start to stall out. You must have heard about mowers that have ground to a halt midway when cutting grass uphill or those that fail to start completely. Such is a situation that signals a lack of enough fuel in the combustion chamber.

When the filter is clogged with dirt, not enough fuel goes through. Your machine may start but stalling incidences become commonplace. The catch here is that there should be surplus gas going through the filter so that the engine does not get deprived at some point. Make sure to check the filter for any defects as soon as your lawnmower starts to stall out. If the filter is not clogged upon examination, chances are high that the fuel line is the problem.

Cleaning lawn mower fuel filter

Fuel filters that do not fill up are easy to detect. It only takes a few easy steps of inspection. You should also note that because filters prevent dirt from getting into the engine, leaving them unattended can render your mower less or completely inefficient. The engines could get damaged, and that means costlier maintenance and repair. You, therefore, would not want to wait until it is too late to clean clogged filters.

Before cleaning the filter, find out if it is paper/nylon or metallic. While metallic filters are easy to clean, you may have to replace paper ones-ostensibly the best advice any experienced homesteader would give.  Steps to cleaning metallic filters include:

Step 1: Relieve fuel lines of pressure

Start by relieving the fuel system of pressure. To do this, locate the fuel pump fuse, remove it then run the engine for at least two minutes. Provided you have parked the mower in the open air, everything should work out fine.

Step 2: Remove the spark plug

Disconnect the battery terminals. We advise that you disconnect the negative one. It helps prevent a fire hazard that may result from the ignition of gas fumes in the fuel system.  This is a good time to check your sparkplug, clean them, or replace them if needed. Here you can find spark plugs.

Step 3: Disconnect the fuel lines

Remove fuel lines connecting to the filter with the combustion chamber. A crew wrench should help you perform the task with great ease. You should wear protective clothing, including eyewear when removing fuel lines.

Step 4: Remove fuel filter

Now detach the filter from its seating. Always remember to check its placement so that you don’t have challenges during reinstallation. You should, however, note that some filters, if not most, have arrow inscriptions indicating the direction of installation. If that’s the case with the one on your lawnmower, you reinstalling so that everything is in line with the direction of fuel flow should take only a few minutes.

Step 5: Drain fuel residue and debris from the filter

Drain the filter of any gas/fuel residue by gently tapping it on both ends. When tapping fuel-in and fuel-out nozzles, make sure to drain the remaining fuel into a container.

Step 6: The cleaning stage: Use an ideal cleaner for the carburetor

The next step is cleaning, so you ask-how do you clean fuel filters. We assume that at this stage, you should have a carburetor cleaner ready.  Spray it inside and outside the filter. Finally, tap the filter on both ends to drain it off-gas/fuel residue one more time then leave it to dry in the open air for at least an hour. Here you can find some good carburetor cleaners.

Staying safe when cleaning or replacing lawn mower fuel filter

Always remember to unplug the spark plug when carrying out a maintenance or repair routine. You would be risking your life with the plug on should the engine ignite accidentally. If you are not comfortable with cleaning or replacing filters at home, a reputable dealer should help you do it. We advise that you consult none other than a dealer who sold you the machine for the best filter servicing. You would rather spend a few bucks on hiring a professional to do the work than risk shortening the lifespan of your lawnmower. 

Do I need to replace the filter with a new one?

With the above steps on how to clean clogged lawn mower gas filters, you should have it back to optimal functioning. However, should it not get filled with fuel once you run the engine; chances are high the damage is beyond cleaning and repair. So, you would want to ask, do I need to replace a filter with a new one?

Well, you don’t have to replace a metallic filter every time it gets clogged, unless it has outlived its usefulness. However, you should replace nylon or paper filters as soon as they become clogged. The process of replacing the faulty filter is rather easy because you only need to remove it and plug a new one in its place. Cleaning paper filters, experienced homesteaders note, may cause more damage and harm, making them less effective.

Here you can find lawn mower fuel filters.

How often should you clean the filter?

Another major concern among homesteaders is to do with the frequency of cleaning lawn mower fuel filters. They often ask, should I clean the filter after every use or it should be seasonal? Let’s face it. You will not be mowing turf in your backyard every day or week. Sometimes it may take up to a month or two before mowing down overgrown grass in your compound. With that, you should already have an answer to how often one should clean fuel filters.

For starters, you should note that the frequency of cleaning lawn mower gas filters varies from one machine model to another. According to John Deere, a leading manufacturer of lawnmowers, homesteaders should change fuel filters after fifty hours of use. We translate that to mean changing filters at least once every other season of mowing.

Some manufacturers determine the frequency of cleaning or changing filters based on mileage. Thus, based on our research, you can also clean or change filters in your lawnmower with every ten-thousand to twenty-thousand mileage.

The good news with respected brands is that mowing machines come with user manuals that take you through steps to changing and cleaning fuel filters. You can also reach your dealer through a helpline and get help with troubleshooting problems with filters.

No fuel in fuel filter riding mower

If your fuel filter is not staying full while running a lawnmower for several minutes, it can be due to several reasons:

  • Clogged fuel line: The fuel line between the gas tank and the fuel filter can be clogged. Remove the fuel line and check if it is free. Replace the fuel line if you are unsure.
  • Wrong fuel filter: If you use the wrong fuel filter, it can lead to an empty fuel filter after some time. Check the fuel filter, and replace it if it is not the correct one.
  • Gas Gap: Run the engine with the gas cap off for a while. If that fixes the problem, the air hole in the gas gap is clogged. Try to clear it, or drill an additional hole so air can enter the gas tank.
  • Vapor lock: Use the following trick to fix the vapor lock. Pour some cold water over the fuel lines and fuel pump when the engine is off. This should cool down the gas quickly, and condense it.
  • Fuel valve: Check that the fuel valve is fully opened.
  • Fuel pump: If your lawnmower uses a fuel pump, check that it works well.

Final Thoughts

Troubleshooting lawn mower filters for any damage or clogging is an important step toward ensuring the effectiveness and efficiency of the machine. In this post, you have learned that a mower’s filter should be full so that the engine does not misfire. With a filled-up filter, you also are assured of optimal performance-no debris blocking fuel from entering and exiting it.

Moreover, depending on whether you have a Briggs & Stratton lawnmower or a Honda Harmony, procedures for determining fuel volume often vary.  Lack of enough fuel in the filter has always been cited as the leading cause of stalls, especially when the load is heavy. When exhaust pipes release heavy black smoke and a lawnmower becomes noisy, that’s another sign that you should check the filter. Half-full filters mean clogging, something that poses a bigger risk to the engine’s health.