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How to Clean a Lawnmower Fuel Filter?

Let’s face it. Filters are indispensable accessories in all machines that utilize fuel/gas. Their role is to clean fuel that goes into the combustion chamber/engine. We know you don’t want your lawnmower to start exhibiting engine problems; hence this post couldn’t have come at a better time. Contaminated gas often results in engine failure. The question you should be asking right now is, how should you clean a clogged fuel filter? First off, note that contamination happens because of impurities such as dust particles, rust, and other debris that mix with the fuel. When these find their way into the engine system, problems start. It is also noteworthy that filters are workhorses in lawnmowers hence the need to clean them often.

These are the signs of a clogged fuelfilter:

  • Lawnmower engine stalls when accelerating
  • The engine is misfiring randomly
  • No engine power
  • Physical diagnosis of the fuel filter
  • The engine fails to start
  • Smelly fumes

Clean your lawnmower fuel filter with these steps:

  • Step 1: Park your lawnmower on a flat surface
  • Step 2: Remove the fuel pump fuse
  • Step 3: Disconnect battery terminals
  • Step 4: Disconnect fuel lines
  • Step 5: Eject the filter
  • Step 6: Cleaning the clogged filter
  • Step 7: Use a good cleaner

Now, on answering how to clean fuel filters in lawnmowers, we would say it depends on the type of filter. The frequency of replacing or cleaning clogged filters, however, depends on many factors. Metallic filters are ostensibly easy to clean, albeit they could last for a year or more before a cleaning necessity arises. For paper/nylon filters, the best advice we can give is that you should replace them with new ones as soon as you notice signs of clogging. The problem with cleaning paper or nylon filters is that they easily lose shape hence becoming ineffective.  

Like every part of a lawnmower that contributes to its optimal performance, cleaning improves the durability and health of fuel filters. So, here is the next question: Are you a handyman or a homesteader looking to buy the best lawnmowers? Would you like to know how to clean fuel filters in a push or riding mower? Well, we invite you to dive in with us to learn more. We will shortly explore the nattiest and grittiest of lawnmower filters, especially how to clean them so that they perform optimally.

Signs of Clogged Fuel Filters

For those who do not know the location of a fuel filter in lawnmowers, the answer is simple. It varies from one mower model to another. You can locate it on the fuel line leading to the combustion chamber (carburetor) or in the fuel tank.

When it comes to diagnosing clogged filters, start by taking a keen interest in the engine.  Does it splutter? Does the exhaust pipe produce dark fumes with a foul smell? If your answer to these questions is affirmative, the fuel filter could be the culprit due to clogging. The bottom line is that bad filters have a direct impact on the health of the engine, so here are signs of clogging you should note:

● Lawnmower Engine Stalls when Accelerating:

When accelerating, more fuel goes through the filter and finally into the combustion chamber. However, should the engine lose its power and stall when accelerating, the chances are high that the fuel filter is bad. Clogged filters prevent sufficient fuel flow to the engine hence the occasional stalling when mowing at high speed. We, therefore, recommend that you diagnose the one in your lawnmower for debris and other particles such as rust and dust.

● Engine Misfiring Randomly:

Another symptom of a clogged filter is when a lawnmower engine starts misfiring. If the machine does not splutter, your service provider should diagnose for error codes. Misfiring engines mean that injectors are not getting enough fuel hence the need to diagnose filters for clogging. Note that unless you have one of the latest models of lawnmowers, misfiring should not happen when a lawnmower is parked in gear. The only incident during parking that could further signal filter clogging is the rough idling of the engine.

● No Engine Power:

When less or no fuel goes through injectors, you should expect the engine in your lawnmower to lose its power. Right away, park your machine, then diagnose fuel filters for clogging. With most modern mowers, you will see an error code on the dashboard. It usually happens as soon as the engine goes into limp mode. However, do not overrule the possibility of a fault in the injectors. Sometimes injectors will give you the wrong signal, getting you to think that filters are under heavy clogging. It is why; diagnosis should include other components that connect filters to the engine and carburetor.

● Physical Diagnosis of the Fuel Filter:

You can physically diagnose your lawnmower for filter clogging. To do it, blow as much air as you can through the fuel-in nozzle. If air does not come out through the fuel-out nozzle, there is clogging. Replacement or cleaning, therefore, becomes necessary.

● Engine Fails to Start:

Engines that fail to start are not always faulty like most people would want to believe. You could end up wasting time diagnosing a healthy carburetor or injector. It is often said that clogged filters cause problems in lawnmower engines, and failed ignition is one of them. Whether the engine jerks or fails to start, check fuel filters for partial or complete clogging.

● Smelly Fumes:

Do exhaust fumes produce a foul smell? If that is the case, check the filter for clogging. The most likely outcome would be in the affirmative, hence the need to clean or replace it with a new one.

With the above signs of clogged filters at your fingertips, you should then start the cleaning process. But when it becomes necessary to replace filters instead of cleaning them, stay tuned for guidelines later on in this post.

Cleaning Lawnmower Filters: How to Do It?

Dirty fuel is a sign of clogged filters. But the question is do you know how to clean the fuel filter in your lawnmower? Well, for a novice, you should get help from lawn mowing service providers.  But the catch is that cleaning filters, at least twice every year, should help improve their efficiency in cleaning fuel that goes into the engine. And when it comes to the replacement of worn-out nylon or metallic filters, we recommend that you do it once every year.

Now, on how to clean these gadgets, we did some homework and put together the following guidelines:

  • Park your lawnmower on a flat surface: To get started with cleaning, park your lawnmower on a flat surface, preferably, parking yard or garage. Parking your machine in an open space is one of the many precautionary measures you should take to avoid fire accidents. Remember to wear protective clothing.  
  • Remove the fuel pump fuse: Next, remove the fuel pump fuse, assuming you know where to find it.  With that, it is time to remove pressure from the fuel system by letting the engine run for about two minutes.
  • Disconnect battery terminals: Disconnect the terminals, preferably the negative ones. You could refer to it as removing the spark plug, but the motive is to prevent a fire from a hazard. The risk of not removing the spark plug is that the engine might start on its own, or gas fumes might ignite in the fuel system.
  • Disconnect the fuel lines: Next, using a screw wrench, disconnect fuel lines. Put on protective eyeglasses when performing this task. Accidental fuel spillage could prove detrimental to your eyesight.
  • Remove the filter: Now it is time to eject the filter. When doing so, please take note of its seating to avoid wrong re-installation. A question many people ask in this regard is what happens when you install filters wrongly? Will fuel flow in the opposite direction? We will tackle these questions later on in this post. For now, the good news is that some fuel filters have labeling that indicates the direction of installation, so it is only a case of flicking it back to position.
  • Cleaning a clogged fuel filter: Cleaning a clogged filter should take about 10 to 15 minutes. In cases of partial clogging, five minutes is enough. Start by draining fuel/dirt/debris residue by tapping the filter on both ends (fuel-in, fuel-out nozzles). Be gentle at it and drain fuel filter residue into a container.
  • Use a good cleaner: You should always use a good cleaner, preferable that for carburetors when unclogging lawnmower fuel filters. Spray it inside and outside, then tap both ends one more time. Leave the filter in the open air to dry, say for an hour or two.

Safety Precautions to Consider when Cleaning Filters

You would rather be safe than sorry when cleaning dirty fuel filters. Thus, take precautionary measures at all times. Wear protective gear, preferably clothes that you won’t mind getting tainted with oil/fuel.  Protective glasses are equally necessary to guard your eyes. Moreover, always pull off spark plugs. You don’t want to end up with a situation where the mower starts on its own while working on the filters.

In a nutshell, leaving spark plugs on is a recipe for an accident and fire hazards.  You can always contract a lawnmower service provider to help you with cleaning filters if you are a first-timer.

Replacing Fuel Filters: What You Need To Know and How to Do It

We indicated earlier that the best thing you should do with paper and nylon filters is to replace them as soon as signs of clogging show up. But the begging question is that do fuel filters have a lifespan? Well, in most cases, replacing filters every two years is a good rule of thumb. Alternatively, you can have a mechanic diagnose the fuel lines to determine if there is a problem with the filter before taking any action.

Some mechanics recommend that filter replacement should take place after every 20,000 miles of mowing. Of course, that will depend on how often you use your lawnmower, but a pressure test should further help resolve any misgivings. While mileage is an important factor, it should not be a rule of thumb. It is because some manufacturers recommend cleaning filters only after clocking 30,000 miles in mowing.

A pressure test aims to determine the amount of being generated at the fuel rail. Low or reduced pressure-often below 30 psi is a signal that there is clogging in the filter. When you don’t replace faulty filters, the engine’s health will be at risk. Moreover, regardless of the filter location, you should be wary of idling problems with the engine, including other symptoms of clogging we explored earlier.

We also advise that you check product user manuals to learn more about filter cleaning and replacement. You should not risk doing something because every homesteader does it; rather, knowing every filter manufacturer has specific rules is an important step as we advance.

Now, when it comes to replacing faulty or clogged paper/nylon filters, it should take only a few steps. They include:

  • Park the lawnmower: Park the lawn mower on a flat hard surface then let the engine cool down.
  • Use the right gear: Wear proactive gloves then use a screw wrench to remove the fuel lines that connect the filter to the engine/combustion chamber. You can also use a pair of pliers. When removing the filter, ensure there is a plastic container underneath into which fuel residue will run.
  • Loosen the filter: Move the fuel lines away from the filter by slight outward sliding on both ends. Now, loosen the filter by twisting it slightly as you let fuel residue drain into a container.
  • Examine the filter for faults: Diagnose the filter for any faults and compare it with the new one before deciding on whether to replace or clean it (for metallic filters). You should replace paper filters right away because they are hardly reusable.
  • Install the new filter: When installing a new one, ensure it flicks back tightly into position and in the right orientation. The good news is that most filters have labels indicating the direction of installation.
  • Clamp the fuel lines: Slide back the clamps holding the fuel line into the nozzles on both ends of the filter, tighten then wipe them clean.

Once you follow the above steps to the letter, power on your mower, then run it to tests the filters once again. Does the engine jerk? Does the engine misfire or fail to start? Should you spot any of these problems, the chances are high that the new filter is faulty or you missed a step in the installation/cleaning procedure. We would recommend that you consult your seller/manufacturer or service provider for further advice. You should also note that the procedure for removing filters sometimes varies depending on the type of lawnmower-a push or riding mower.

What is the cost of cleaning/replacing dirty fuel filters?

Before diagnosing lawnmower fuel filters for clogging, you may want to ask a few questions.  For example, what is the cost of cleaning filters if you choose to hire a lawn service provider? Also, how much does a new filter cost if you go the replacement way?  Well, for those who mow less often, say, during spring only, fuel filter maintenance costs are significantly low.

However, if you run a mowing business, cutting grass over several miles of lawns every single day costs more money, especially in maintenance costs. The catch here is that machines wear and tear out fast with frequent use, so you should expect filters to clog faster when you are mowing frequently.

Moreover, cleaning or replacement costs can vary depending on the extent of damage to the fuel line and the engine. It means you may have to clean or replace other parts too in the processing of unclogging filters. Given that cleaning filters call for a routine maintenance practice doing it alone will save you some bucks. But if you choose to hire a service provider, charges could go higher depending on the company you contract for the task.

We did a quick online search and found out that replacement cost averages between $5 and $200. You can get a brand new filter at Walmart for at least $6 or at most $45.  Mr. Tire will charge you money in the range of $70 on the lower side or $215 on the higher side. We also compared prices on Amazon and noted that a good spare filter should cost you money that averages $110 on the higher side or $8 on, the lower side.  Remember that these prices vary depending on, among other things, model and manufacturer and shipping costs.

Can you save money when replacing paper/nylon filters?

Yes, you can save money on filter replacement. We know how much it means to have a few extra bucks in your pocket after buying the best fuel filter for your lawnmower. Pure bliss! You should, therefore, do the following:

  • Buy a replacement filter: Get a tiny replacement filter during annual lawnmower servicing as part of the maintenance and care routine saves money. If your service provider does not charge extra money for cleaning, the better.
  • Check for affordable prices: Apart from cleaning clogged filters, change is as good as necessary. Thus, another way to save money on a new filter replacement is to shop around for the best prices. Check out prices on Walmart, eBay, manufacturer websites, and Amazon, including shipment cost, before deciding on the cheapest or affordable option.
  • Consult the manufacturer: Always consult the manufacturer of your lawnmower for advice on cleaning/changing fuel filters. They may offer an alternative approach that saves money, such as using aftermarket spares instead of OEM accessories.

The bottom line is that cleaning and replacing these vital components of your riding or push mower is a pretty straightforward process. If you want to save more money, doing everything on your own at home is the best bet. It is especially workable if you will not need the input of a specialist. Moreover, avoid ordering wrong replacement filters before consulting repair specialists or the manufacturer of your mower. You don’t want to damage your machine because of ignorance.

What happens if you wrongly install a fuel filter after cleaning?

Lawnmower fuel filter installation should be a pretty simple process. However, sometimes mistakes happen. Take, for example, installing a filter backwards? What would happen? Will fuel flow normally or could it trigger a serious engine failure?

These questions can go on and on but let’s admit that fuel filters for lawnmowers vary in design. While most, if not all, have a direction of installation clearly indicated on the gadget, there are instances where installation can take place backwards, and nothing bad would happen to your push or riding mower. However, you should take note of a few signs that may indicate the wrong filter installation. They include:

  • Installing the filter in reverse: In some cases, installing filters backwards either stops or restricts fuel flow. You may have to open the gadget to check the arrangement of filters to determine whether installing it in any direction is okay or not.
  • Access the engine after installation: Test the engine as soon as you finish installing filters. Should it fail to start, you may have to remove the filters and re-install them correctly.
  • Pump failure: Sometimes pump failure signal wring filter installation.

With the above indicators at your fingertips, you would want to also ask, how then does one install fuel filters correctly?

What is the right way to install fuel filters?

Well, let’s reiterate that the latest models of fuel filters have symbols/labels that show the direction in which you should install them. Should you feel something is wrong, a quick inspection should help clear any doubts about wrongdoing.

However, the rule of the thumb is that the installation arrow as indicated on the filter should be in the direction of fuel flow. It is also the way of the carburetor into which gas gets after leaving the fuel lines. According to Briggs&Stratton, a leading manufacturer of lawnmowers, they always install filters with the larger end towards the gas tank. It is especially applicable for filters that do not have arrows indicating the direction of installation.