If you take a look at your lawn after you have finished mowing, you might find that some areas are cut lower than others. In some cases, you might even find that the lawn is cut so short that there isn’t much grass left. Thankfully there are a few different things you can do to stop your lawn mower from scalping your lawn. Let’s take a look.
Why Does Your Mower Deck Keep Digging Into the Ground? (The Short Answer)
The most common reason your riding mower’s mower deck is digging into the ground is that you have an uneven lawn, and while you mow, in some sections, the deck is able to get lower to the ground. Bumps and potholes are two areas in the lawn that will cause this. The scalping can be made worse if you drive too fast.
Mower Deck Gauging the Ground (3 Possible Causes)
To better understand why your lawn mower deck is digging into the ground, you first need to make sure there are a couple of things set correctly on your lawn mower. Mainly, you need to ensure that you have tire pressure set correctly for all your tires and that the deck is level.
If either of these two items is incorrectly set, then you’ll probably have continuous scalping and an uneven cut all over your lawn and not in certain areas. So double-check your lawn mower is set up correctly, then you can take a look at where the real problem lies.
Mowing Uneven Ground
The number one reason your lawn mower deck will dig into the ground is that the ground is uneven. If there is a bump in the lawn or a dip, then the mower deck and cutting blades are going to be brought closer to the ground than you intended.
The result is your lawn mower will scalp the grass. So, jump off your lawn mower and take a closer look at how uneven the ground is where your lawn mower is scalping.
Driving Too Fast While Mowing
Next on the list is driving too fast while you are mowing your lawn. If you find that your ride is bumpy and you are bouncing around, then it’s pretty clear that your lawn isn’t all that flat. So, driving at a high speed is just going to make it worse.
I’ve seen this be a problem for people, especially when they are turning their riding lawn mower at the end of a strip. Even though the lawn may be flat, if you’re turning too quickly, then the weight of the lawn mower will be shifted to one side and cause the deck to dig into the lawn. So, adjusting your driving speed could help avoid scalping your lawn.
Anti Scalping Wheels are Not Set Correctly
If you take a close look at your riding mower, you will probably find a set of wheels attached to the cutting deck. These are the anti-scalping wheels.
Now, manufacturers know that the bigger the deck becomes, the more susceptible your lawn mower will be to scalping. So, they have included anti-scalping wheels within the design to avoid this. These wheels basically only allow the deck to lower to a certain point and not more.
For example, if the wheels are set to three inches, then the blade shouldn’t be able to come any closer to the ground than three inches.
Now, anti-scalping wheels are not perfect, but they are certainly an improvement. So, take a look to see if your lawn mower has anti-scalping wheels, then check to see what height they are set to.
How to Stop Your Mower Deck from Digging Into the Ground
Now that you have had a look through what I believe to be the 3 most common reasons why your lawn mower deck is digging into the ground when you mow, let me share with you the steps I take to overcome scalping.
Level Out the Ground
If you have found a hole or two in your lawn where your mower deck is digging into the ground, then you can grab a bag of topsoil from the gardening store and fill it in. This is going to stop your mower wheel from dropping into the hole and causing your lawn mower to scalp the grass.
I’ve had a number of occasions where my irrigation has broken in the yard and caused dips around the heads. I only found out about the holes when my lawn mower wheel dropped into them. So, a bag of topsoil comes in handy.
But what do you do if your lawn mower is scalping a hump in your lawn? Well, in cases like these, I avoid using the lawn mower altogether. You might find that no matter what you try, your lawn mower will never stop scalping certain parts of your lawn that are raised. Instead, try mowing these areas down with a weed eater.
There are several raised areas in my yard where I know my lawn mower is going to make a real mess, so I don’t even try anymore, and I pull out the weed wacker.
Slow Down over Bad Areas
I’m as guilty as the next person when it comes to sometimes driving my lawn mower too fast. But I’ve had to learn my lesson the hard way. Not only does mowing fast give an uneven cut to most of the lawn, but it really makes the scalping worse. So, try to go just a bit slower and take your time. This includes slowing down when turning at the end of a strip.
Adjust the Anti-Scalping Wheels
If you have never set the height of your scalping wheels, then they will be set to the factory settings. Now, this can be at either the maximum or minimum height. It really depends on the manufacturer.
So, the first thing to do is grab your user manual and find out what the adjustments are. Usually, the manual will state what each of the anti-scalping mounting holes means. As an example, the bottom hole might be 4 inches, and the top hole might be 1 inch. So, if your wheel is set at the 1-inch height, the deck can get all the way down to 1 inch. This is super low and definitely scalping territory.
On the other hand, if the anti-scalping wheel is set to 4 inches, then even if you set your mower cutting height less than this, the anti-scalping wheel will prevent the deck from lowering. If the anti-scalping wheels are set to 4 inches, and you adjust the deck lever to 3 inches, the deck will only drop as low as what the anti-scalping wheel is set to. In this case, it’s 4 inches.
Let’s take a look at how to set the height of your anti-scalping wheels on your lawn mower deck to reduce how much your mower deck is digging into the ground.
Steps to Adjust Anti-Scalping Wheels
- First, lift the cutting deck to the required cutting height for your grass.
- Place your wrench onto the mounting bolt of one of the anti-scalping wheels.
- Place your socket wrench onto the mounting nut connected to the same anti-scalping wheel.
- Using your tools, remove the nut from the mounting bolt.
- Pull the bolt from the wheel.
- Repeat the wheel removal for all the anti-scalping wheels.
- With your deck set to the required cutting height, position the anti-scalping wheel in its mounting location.
- Raise the anti-scalping wheel so that it is ¼ inch off the ground.
- Line up the wheel to the closest mounting hole, making sure that the distance between the ground and the wheel is still ¼ inch or above.
- Install the bolt through the mount and the anti-scalping wheel, ensuring all washers and bearings are installed correctly.
- Reinstall the nut and tighten it to the required torque.
- Check that the anti-scalping wheel still spins correctly.
- Remeasure the height between the ground and the anti-scalping wheel.
- Repeat the process for all anti-scalping wheels.
Tools Required to Adjust the Anti-Scalping Wheels
- Socket Wrench Set
- Wrench Set
- Torque Wrench
- Measuring Tape