Most lawn mowers are not overly complicated machines –powered by you or a motor/engine, there’s a blade that spins around and not much else – but they do have to be kept in proper working order to do their job. If one part of the equation is out of sync, there will be trouble. And when it comes to the blade, it’s uber important that it’s sharp and balanced, as that’s obviously the part that does the dirty work, i.e. cuts the grass.
If your lawn mower blade is bent, it’s not going to cut right. Furthermore, it’s now turned into a liability for both your own personal health and that of your lawn mower. Bent lawn mower blade symptoms include an uneven cut and higher-than-normal levels of vibration.
Bent Lawn Mower Blade Symptoms: What Will You Notice
We’re going to cut right to it (pun intended!). If you hit a stump, rock or any other type of hard object, it’s possible that you could have bent your mower blade. A blade spinning at high speed, colliding with a solid object isn’t a good mix. Without flipping your mower over, you won’t be able to tell for sure if it’s damaged, but there are a few bent lawn mower blade symptoms that you can look out for to give you a good idea:
A small amount of vibration is normal when using your lawn mower. But if you’ve noticed that this vibration has significantly increased, especially if it coincided with hitting a rock or something similar, there’s a good chance that your blade has been bent.
You see, when a blade is bent out of shape, it becomes unbalanced, and this is what causes the additional vibration.
Next, look down at the grass after your mower has passed over it. You might need to get down on your hands and knees here to really spot this. Is the cut level? Or is it scruffy-looking, almost like a hacksaw has gone over it?
If your lawn mower is cutting unevenly, it can be a sign that your blade needs sharpening, but it’s also one of the more common bent lawn mower blade symptoms. Especially if this deterioration in cut quality has happened quite suddenly.
Are you hearing grinding noises that sound like they’re coming from the underside of your deck? This is another sure sign that all is not well under there and could indicate that your mower blade is bent.
Your Lawn Mower is Stalling
If you continued to use your lawn mower after the blade was damaged and bent, it’s possible that you may have also damaged the crankshaft. It could also have been damaged on impact, like the blade. Either way, a bent lawn mower crankshaft will usually result in further engine damage if you continue to run the mower, and if you notice that your mower keeps stalling, that’s likely what has happened.
Other Parts of Your Mower You Should Check
After looking at the blade, there are a few other key components that you’ve going to want to check too, because replacing a damaged blade isn’t going to do any good if other parts of the mower have been damaged too. These other components that you’re going to want to check include:
- Blade adaptor (these often get damaged too)
- Crankshaft (pray that it’s ok!)
- Flywheel key
If any of these parts are damaged, you’re going to need to fix them before you start your mower up again.
The Solution to a Bent Mower Blade?
Providing none of the other mower parts we just mentioned have been affected, you can get on with solving the issue of a bent mower blade. You can forget about trying to straighten it out. I know in an ideal world, you would, and it’d be great for the environment. But the chances of you actually getting the blade properly straight again are very slim, and if you refit it and use it while it’s still bent, you’re asking for trouble.
So tilt your mower over after removing the spark plug/disconnecting the battery or power cord from the mains, and proceed to remove the bent blade. Make sure your replacement blade is the same size, and has the correct center hole, make sure the blade is the right way up, and then secure it in place.
How to Avoid a Bent Lawn Mower Blade
Prevention is always better than the cure, right? So here are a few tips to help you avoid a bent blade in the future.
Know the Layout of Your Yard
The first step in avoiding a bent mower blade is honestly just being aware of the layout of your yard and what it contains. Where are the obstacles located? Are there stumps or tree roots that are not that visible to the eye? Once you’re aware of where these permanent dangers are located, you’ll know where you have to mow with a little more care.
Comb the Yard Before You Start
While the first step ensures you’re aware of all the permanent dangers in your yard, other “temporary obstacles” can appear too. A stray rock your dog pulled onto the lawn, toys that your kids have left out, etc. Any number of things.
So before you start, have a quick walk around your lawn, and pick up anything that’s in the way.
Be Extra Careful in the Fall
This is the trickiest time of year in terms of avoiding obstacles that could bend your mower blade, as there’s a lot of debris that can mask the lawn’s surface and hide obstacles. You then mow over them, none the wiser, hear a nasty bang, and end up with a bent blade.
To combat this, if the lawn is covered with leaves, what I’d recommend you do is raise the cutting height quite a bit higher than normal, and that should ensure you clear whatever is hidden and protect your mower blade.