What Size Wrench Do I Need to Remove a Lawn Mower Blade? (Solved!)

Generally speaking, a lawnmower blade can be changed with a 15/16” wrench. However, this can vary based upon the model of lawnmower that you have. 
You will always be able to find information on the size of wrench that you need in the user manual for your lawnmower.

What size nut do lawn mowers have for their blades?

This will be dependent on the lawnmower that you have. The vast majority of lawnmower nuts are going to have 5/8” thread.
It is unlikely that the manual for the lawnmower will list the size of the nut. Instead, they will just sell the nut as a spare part.

Do you need a special wrench to remove a lawnmower blade?

In most cases, no. There are some models of lawn mower that will require a special wrench to remove the blade. However, these are few and far between.
All of the top lawn mower manufacturers on the market just need a standard wrench to remove the blade.

Can you use an adjustable wrench to remove a lawnmower blade?

You can. However, it is not recommended. Most lawnmower blade nuts are incredibly tight.
Because they are tight, you may find that you are likely to break an adjustable wrench, particularly if it is on the cheaper side of things. We recommend that you buy a proper wrench as they are not too expensive.

Can you use a socket wrench to remove a lawnmower blade?

Yes. In some cases, it may even be easier to remove a lawnmower blade with a socket wrench.

Can you overtighten the nut on a lawnmower blade?

Yes. You only need to tighten the nut until you can no longer turn it in huge amounts. If you over tighten, then you run the risk of sheering the nut and the bolt. This can make it difficult to remove in the future.

Can you replace the nut on a lawnmower blade?

Yes. In most cases, you can.
In many cases, the nut will be a typical nut that you can purchase from your local hardware store. You will also be able to purchase the nut as a spare part from the company that manufactured your lawnmower.
Do bear in mind that if you purchase the nut as a spare part, then it is going to be much more expensive.

Do you need a torque wrench to replace a lawnmower blade?

No. There is absolutely no need to use a torque wrench. While the blade needs to be secure on the lawnmower, you do not have to get it an exact tightness. As long as the blade is secure, then you should be fine.

What do you do if the lawnmower blade nut is stuck?

You can spray a small amount of WD-40 onto the nut. Leave it to seep in for about 30-60 minutes. You can then try and undo it again.
Once the nut is off, you may want to clean around the area. It is not uncommon for lawn mower blade nuts to become clogged with gunk from mowing the lawn.

What do you do if a lawnmower blade nut is rusted?

In some cases, using WD-40 should be able to free up the mower blade nut. You will need to replace the nut afterward. You should never put a rusted nut back onto a lawnmower as it is dangerous.
If you still can’t remove the nut, then you will need to take the lawnmower to an expert. They will either be able to cut or drill the nut off for you.

Can you rethread a lawnmower blade bolt?

You possibly can, but we would not recommend it. If the thread on the bolt has been worn down, then we suggest that you just buy a new blade assembly. It is going to be so much cheaper and a whole lot less hassle for you.

What equipment do you need to remove a lawnmower blade?

You will need the correct size wrench. We also suggest that you purchase a good pair of thick gloves. This is because lawn mower blades, even when they are dull, can be exceedingly sharp.
The heavy-duty gloves will help to protect your fingers when you are removing the blade.

Do you have to screw a lawnmower blade on?

It depends on the model. Most models will just require you to push the new lawnmower blade onto the bolt. However, there are a few models where you may have to screw the lawnmower blade into place.
It should be easy to see how your lawnmower works by looking at the lawnmower blade.

How often should you be replacing the lawnmower blade?

You may need to sharpen the lawnmower blade at least once or twice per cutting season. It is actually rare that you will ever need to replace a lawnmower blade.
Most people, at least when using a lawnmower around the home, will only need to replace the blade every few years.

How do you know when you need to replace a lawnmower blade?

You will know that the lawnmower blade needs to be replaced if it is starting to develop chips or cracks. Chances are that if the lawnmower blade is just blunt, you will be able to resharpen it.
If you do need to resharpen your blade, you can do it yourself or take it to a professional.

Are lawn mower blade bolts reverse thread?

It does depend on the model. The vast majority of them are reverse threads. This means that you will have to turn the wrench clockwise to undo it.
This is to ensure that the nut does not come off when the lawnmower is being used.

Which way do you put a new lawnmower blade onto your mower?

On most lawnmower blades, there will be either arrows or words that indicate which direction you need to place the blade.
You mustn’t mount your new lawnmower blade upside down. If you do, then there is a chance that it will not cut anything!