How Often Should Lawn Mower Blades Be Replaced?

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To ensure that your lawn maintains that attractive and well-manicured look, it is important that you inspect the blade of your lawnmower after every use to make sure it is still sharp and more importantly, damage-free. Together with making your lawn look healthy and neat, regular inspection of your lawnmower blades can also help to ensure the proper growth of your grass. Once you notice that your blades are dull or chipped, then they must be sharpened immediately. However, if the damage is beyond repair, or you notice large debts or chips on your blade, then a replacement is highly recommended as sharpening it will only do more harm than good.

How Often Should Lawn Mower Blades Be Replaced?

Depending on your usage lawnmower blades can last at least 200 hours or longer. If the grass is unevenly cut, or a hard object is hit check the condition of the blade. Mower blades normally need to be sharpened every 25 hours, but when the blade is damaged it needs to be replaced.

How Often Should Lawn Mower Blades Be Replaced? 1
(CC BY-SA 2.0) by osde8info

Regardless of how often you use your lawnmower, the blade can easily become dented, chipped, worn out, and damaged, which could be as a result of hitting hard objects such as rocks and wood chips, or continuous use over time. This is why you should inspect your blades regularly, as damaged blades can actually become dangerous to you, and can also damage your mower.

One of the ways to check whether your lawnmower blade needs replacement or not is to look at the lawn after you mow. If you notice any uneven patches or missed spots, then it’s a sign that your blade needs some sharpening or sometimes, total replacement. In order to ensure the health and neatness of your lawn, it’s essential that you sharpen or replace your lawnmower blade regularly. Are you looking to replace your lawnmower blade? Do you want to know how to replace your lawn mower blade(s)? Don’t worry, this article will provide all the necessary information that you need as regards replacing your lawnmower blades.

When you Need to Replace Your Mower Blades

Once your lawn mower blade gets damaged or probably when the blades have been sharpened too many times, it is recommended that you either replace them with a set of used blades (in good condition), or an entirely new set of blades. Generally, regardless of the frequency by which they are used, lawn mower blades tend to get dented, worn, and damaged easily, especially when they hit some hard objects like rocks and wood chips. Hence, if you haven’t changed your blade in a while but have sharpened them multiple times, then you should consider replacing them to avoid any damage to your mower. Below are a few signs to look out for to know if your blade needs to be sharpened or replaced.

● Uneven Length of Grass

One of the first things you’ll notice when mowing with a blunt blade is that your lawn won’t look as great as it usually does. You may notice uneven patches, or realize that you have to go over your lawn several times before its cut right. This is because when using a dull blade, it will require a lot more effort to mow your grass and you’ll even need to compensate for the missed patches to get desired results. However, if you’re cutting with a sharp blade, you’ll realize that you easily make passes over your grass once, and each piece of grass is cut to the same height. So if notice that mowing has become more of an effort and is more time consuming than usual, then it is likely a sign that your lawnmower blade needs replacing or sharpening.

● Torn or Uncleanly Cut Grass

Another sign to look out for is the way your grass looks after cutting. After mowing your lawn, you can inspect it to see whether each piece of grass is cleanly cut. If you notice that the grass blades look torn, rather than cleanly-cut, then it may be time to either sharpen or change your blade. If you choose to ignore and cut your grass with a dull blade, it can affect the overall health of your grass, causing it to lose its lushness, its fresh green color, and can even encourage the growth of grass diseases and infections. Before this condition occurs, you should replace your blades as soon as possible as damaged blades can be very harmful to the health of your lawn.

● Condition of the Blades

Another way to know if your lawn mower blade needs replacement is to inspect the blade itself. Usually, you should be able to keep your old blade once it is sharpened, however, if you notice chips or large dents in the blade, then you may need to replace it. Also, you should look out for the thickness of your blade as it can erode over time due to the compilation of debris like sand and dirt over time. All these can cause the metal to become thinner and weaker. Once you notice this, then it is definitely time to replace the blade. It is generally safer to replace the blade immediately you notice any problem than to wait for it to break during use. If a blade breaks when you’re mowing, it can be extremely dangerous as a piece of metal mighty fly off and injure you or anyone close to the area.

How Often Should Lawn Mower Blades Be Replaced?

As a general rule of thumb, it is recommended for an average homeowner to sharpen their lawnmower blades at least once a year, at the start or end of the mowing season. Check if the blade is not dented, chipped, worn out, or has other damage. In that case, the blade needs to be replaced. Of course, if you hit a hard object the blade needs to be checked immediately.

Before you start to replace the blades yourself, it is essential that you inspect them properly and consult the user’s manual that comes with it to know about the safety instructions, warranty, and the right blade to use. It is highly recommended that you wear protective equipment and heavy-duty gloves when working on the blades of your mower. There are some common errors homeowners make when it comes to replacing the blade of their lawnmower. These include:

  • Sharpening too often: Thinking that sharpening mower blades regularly will prolong its lifespan.
  • Replacing instead of sharpening: Replacing blade even though it can be sharpened
  • Emptying the fuel tank: Not emptying the fuel tank before tilting the mower to its side
  • Wrong direction: Fixing the blade in the wrong direction
  • Experience: Trying to replace blade without prior experience.

How to replace lawnmower blade

You can replace the blades of your lawnmower in the few easy steps below

Step 1. Disconnect the ignition wire and drain the gas:

Disconnect the ignition wire from the spark plug. If you’re using a cordless mower, remove the battery pack. This is to prevent the risk of the engine accidentally starting up while you’re working. You should also drain the gas tank so it won’t spill any fuel while you’re working on the blades.

Step 2. Tilt the mower:

Tilt the mower on its side to expose the nut or bolt that secures the blade to the mower. Wedge a short wood block between the end of the blade and inside surface of the mowing deck to keep the blade from turning. Then use a wrench and socket to loosen the nut or bolt. To increase the leverage when loosening any stubborn fastener, you can slip a metal pipe over the wrench handle.

Step 3. Remove the blade mounting bolt:

Use a socket wrench of the appropriate size and unbolt the mounting, while using your other hand to keep the blade from turning. Be careful not to lose any washers or mounting hardware that hold the blade into place, which can be reused.

Step 4. Note the position of the blade:

Remember to make a mental note of which side of the blade faces downward. It’s important to bolt back the blade in the same orientation.

Step 5. Mount the new blade:

Mount the new blade in the right direction. Line up the blades as they were lined up before and reinstall the washers and nuts. If you have the owner’s manual, you should find the torque specs for tightening the nut. If you don’t, just make sure you don’t over-tighten it, as this can cause vibrations in the mower. Also, be sure that the length of the blade is the same as the old one before mounting it. Tighten the new blade to the bolts carefully, since it’ll most likely be sharper than the old one. Make sure you’re wearing heavy-duty gloves when doing it, to prevent any injury.

Step 6. Check the blade:

Be sure that the blade is mounted properly and firmly, and has no wobble when you move it up and down. Remove any props that were used to hold the mower in place and wait for about 30 to 60 minutes for the oil to return to the motor to prevent motor damage.

Step 7. Reattach the spark plug wire:

Refill the gas tank and reattach the spark plug wire. Then do a quick inspection before mowing. Check the air filter to make sure that oil does not saturate the foam filter, After the quick inspection, your mower should be able to run, and start cutting grass much more efficiently than before!

Final remarks

That being said, the best way to know if and when your lawn mower blade needs to be replaced is to pay close attention to the condition of your grass. Also, inspect the blade regularly, as this will help you determine whether your lawn mower blade needs to be sharpened or replaced. Good luck!