Common lawn mower problems, care and maintenance tips

Any homeowner with a lawn understands the importance of lawn mower maintenance. The lawn mower is, after all, a critical piece of equipment that enables you to take care of your lawn safely and efficiently. A lawn mower that is functioning at full capacity is an asset, while a poorly maintained mower can be an expense hog as well as a safety hazard. Understanding lawn mower maintenance is a key aspect of avoiding any lawn mower problems that could affect your machine.


In general, lawn mower maintenance or troubleshooting is a fairly straightforward task. Following simple tips and safety procedures can help you keep your lawn mower in prime condition for years to come. You will often find that some of the more common lawn mower problems can be solved in your own backyard

Identifying Stale Fuel

One factor that is often overlooked is the fuel used by a lawnmower. Typically, this fuel has a fixed period of time during which it should be used. Most experts estimate that the ideal period of use is 3 to 4 weeks after it has been pumped into the lawnmower. In many cases, people attempt to start up a lawnmower that may already have gas in the tank from the past season. This is likely to cause problems to the mower engine, and in many cases the machine will not start.

You can check the freshness of the fuel by smelling it. If you get an odor that is similar to that of fresh gas, the fuel is good enough to run your machine. If the odor resembles that of varnish or nail polish remover, the fuel should be considered stale. Another method of testing the fuel is to dip your fingers in the fuel. If the fuel feels cool to the touch it is generally good enough to use

Cleaning the Underside of Your Lawnmower Deck

In order to clean the underside of the lawnmower, you will need to keep some type of a scraper, such as a paint scraper, and a water hose/sprayer ready for use. For the most effective maintenance you should attend to your lawnmower every time you use the machine. After you have completed mowing your lawn or garden, you should rinse out the underside of the deck with a sprayer. This helps get rid off any blades of wet grass that may be trapped. You are probably aware that any moisture trapped to the lower surface of the deck is likely to cause rust. This is bound to weaken the structure of your machine and reduce its life span.

However, most people are unlikely to wash down the lawnmower every time it has been used. As a result there is likely to be grass as well as deposits of mold that are attached to the underside of the deck. You can make use of the scraper to remove the bits of grass and mold that are trapped here. This is quite a simple process. All you need to do is stick the scraper into the clumps of dried grass and mold and pull them out. Another factor that should be considered is that these build ups of mold and grass may place excessive stress on your lawnmower that results in vibrations during times of use. This may lead to frequent breakdowns. After you have removed these deposits with the scraper, you should wash down the deck using your water sprayer.

Lifting a Lawnmower Safely

Before you undertake any lawnmower repairs such as changing the oil or blades, or cleaning the deck, it is important to know the ideal method of positioning the machine. The lawnmower should never be turned on to its side and should never be tilted forward (or up) while you are working on it. This can be critical if you have not drained away all the fuel and oil from your lawnmower. Tilting your lawnmower up will push any fuel into the cylinder and you are likely to vapor lock the machine. This means that the lawnmower is not likely to pull over because the cylinder is filled with oil or gas. This may also cause the fuel to mix with the oil. When the oil is diluted, there is not likely to be adequate lubrication to run the lawnmower engine.

The best way to service your machine is by tilting it backward. Choosing to tilt it over the porch or fence are probably the best options. This allows you to wedge the handle under the fence or porch and maintains a fixed, secure position while you repair the machine. You may also use a bungee cord to secure your lawnmower in the ideal position. Attach one end of the cord to the handle and the other end to an immovable/weighted object. Of course, if you can get a friend to hold the lawnmower during the repair process, there is nothing better.

Storing the Lawnmower Safely For Winter

Not everyone has a garage where they can store their lawnmower. This can be a bit of an issue, especially during winter. The lawnmower needs to be stored safely where it is not affected by rain or snow that can cause rusting and other such problems. Before storage though, you might want to make sure your lawnmower has been cleaned thoroughly. Wash it down with a water hose until all accumulated debris are removed. Remember to avoid spraying water directly at the air filter or any other openings that are present on the lawnmower. As far as possible, avoid getting any water in the gas or oil tanks. (It is advisable to drain the oil and gas out of the mower before storing it.) After cleaning the mower, it is important to allow it to dry before storing it. Tarp is the perfect material to cover the mower and keep it safe during winter. After spreading the tarp over the mower, you may use some rocks or any other heavy object to pin down the tarp in place.

If you do have a shed or garage where you can store the mower, avoid hanging the mower. This will prevent any of the oil/gas in the mower from leaking.

Changing the Blades on a Lawnmower

If your lawnmower is not cutting through grass efficiently, you will probably need to change the blades on the mower. In order to make this change you will probably need a heavy duty ratchet that provides adequate torque and sockets of different sizes. (Typically between 1/2 inch and 11/16 inch) Also make sure that you have a replacement blade that is compatible with your particular mower. Test the sockets to make sure you have one that fits your lawnmower blade bolt perfectly. Attach the socket to the wrench and ensure that it is tilted upright and firmly locked in place over the bolt. To maintain safety, use gloves while you hold the blades. You can then remove the bolt, which should release the blade. Usually, there are several components that hold the blade in place, such as the hardened number 8 bolt, locking bracket, blade adaptor, and blade. Note the order in which these items are removed so that you can replace them correctly. You can now install your new blade; most new blades have a marking which indicates the 'Bottom' side that faces the ground. The first part to put back is the blade adaptor, which has a key way on the inside that indicates the direction in which it should be installed. The adaptor usually has a star pattern on its lower surface that should line up with a similar pattern on the blade. The blade is placed over the adaptor before you push in the bolt to hold the assembly in place. Tighten the bolt manually before using the ratchet to ensure that it is completely secure. Your new blade is now in place and ready for use.

Cleaning the Foam Air Filter on your Lawn Mower

Before you start, make a list of all the cleaning equipment you are likely to require in order to complete this task; cleaning fluid, screwdriver, oil, plastic bag, and paper towels. For the most part, cleaning air filters on a mower is a relatively simple task. Moreover, these filters do not need to be replaced often unless they are torn or broken. The filter may be released by simply removing the screw that is holding it in place. You should try and remove as much of the debris as possible before washing the filter. You can use any type of all-purpose cleaner or even dish soap to clean out this filter. Work a little bit of the cleaning fluid into the foam filter. Use the hose to spray some water in order to push the soap through the filter. You may use the soap again if the filter is excessively dirty. Make sure you wash out the filter thoroughly after cleaning to get rid of any traces of soap. If the filter remains slightly oily after the wash, it is perfectly acceptable, as these filters are supposed to be oiled before use.

Draining the Oil from a Lawnmower

In order to complete this maintenance task on your lawnmower, you are likely to require an oil pan, ratchet with sockets, and regular mower engine oil (SAE-30 weight is an ideal choice). The first thing to do is to tilt the mower back as far as possible in order to locate the oil plug (or drain hole). In a standard lawnmower the drain hole is situated near the blades. Keep an oil pan handy while you work on removing the oil plug. The plug may be removed slowly with your fingers to ensure you are able to catch the oil as it flows out. The oil should drain out in a few minutes; not all of the oil is likely to flow out and a small volume will be left behind. After you have drained out as much of the oil as possible, you may replace the oil plug. Use your fingers to tighten it before securing it with a ratchet. (Note that the plug is generally constructed from plastic and you do not want to apply too much pressure on it.) 

Disposing Stale Gas and Oil from a Lawnmower

It is important to ensure that you dispose used fuel and gas in a safe, responsible manner. This ensures that you do not expose your children and pets to any hazardous materials. You might also end up tainting your lawn and ground water by indiscriminately dumping used fuel. A good solution is to store any waste fuel in a quarter master drain that is easily available at most hardware/automotive shop. This is essentially a container with a filter that traps any debris that may be present in the fuel. Pour out any waste fuel/oil into this container. This container may be disposed at most engine repair or automotive shops for a small fee. Certain garbage pick ups may also dispose this material for a small charge.

Adding Fresh Oil to Your Lawnmower

In general, you can choose any regular lawnmower engine oil, but you need to make sure that it is 30 weight. Also make sure that you have a funnel handy to pour in the engine oil.

You can start by loosening the oil fuel plug and then removing it. If you inspect the top of the oil fuel hole, you will notice a series of threads. Your aim is to ensure that the tank is filled up to the lower end of the threads in the hole. You can pour in the oil gently with the help of the funnel, while keeping an eye on the level of oil that has been filled. Make sure that you fill in the oil until you reach the bottom of the threads. Overfilling the oil tank is not a major issue, and you can simply wipe away any spillage that may occur. Oil is essential to running your lawnmower smoothly and efficiently. Running the machine without oil is liable to cause major damage to the engine or the engine could be totaled. Fixing a broken engine can be very expensive, and is a completely avoidable situation. It is important to check your oil every season. If you happen to use your lawnmower on a regular basis, the oil should be checked every 100 hours.

Replacing Dirty Spark Plugs

Before you start, it is better to gather all the tools you will require to complete this process. You are likely to require a ratchet, new spark plug (ensure that it is suitable for your particular model of lawnmower), and a set of sockets that can help you remove the spark plug. Start by twisting off the spark plug boot. Select a socket of the appropriate size and remove the spark plug. This will now allow you to check the condition of your old spark plug. Look for signs of dirt, carbon deposits, and indications of flooding. If it feels wet to the touch, check for any traces of burnt oil. You can dispose the old spark plug if it dirty and proceed with installing the new spark plug. Make sure that it is re-threaded in at the proper angle. You can tighten it manually before using the ratchet to ensure that it is firmly in place. Replace the spark plug boot tightly and you are all done.

Removing Fuel from a Lawnmower

Draining stale fuel from a lawnmower is an important maintenance task that can help ensure the peak performance of your mower. This can be a fairly simple task on most gas lawnmowers. Simply locate the fuel line, normally situated between the carburetor and gas tank. The fuel line will normally have a clip attached at the tank end. Grab this using a pair of pliers and pull it down the fuel line. You can now slip the fuel line away from the tank. When the fuel line is released gas is likely to gush out of the tank, so cover the tank opening with your finger to stop the fuel spilling over. The gas tank is essentially attached to the mower by some rubber melting. If you wriggle the tank about, it will come loose. You can now empty out the contents of the fuel tank into an empty container. Once the tank has been emptied of stale fuel, you can slide it back into place. There is a small notch on the mower which makes it easy to replace the fuel tank. You should now reattach the fuel line to the gas tank tube. With the pliers, grab the fuel line clip and slide it back to the fuel tank end. You can now fill fresh fuel into your lawnmower and your mower is ready to be used. As mentioned earlier, do not dispose stale fuel in your backyard, but make sure you get rid of it safely.



Disclaimer: The information provided has been prepared as a guide only and the steps taken are likely to vary for different appliance models. We strongly recommend using a qualified engineer to undertake major repairs and fault finding.


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