If you compare a selection of ride-on lawn mowers, you’ll see that some of them have wheels on the deck, and some don’t. So, not everybody has to worry about mower deck wheels. The first ride-on mower I ever had was kind of small, and there weren’t any wheels attached to the deck. But when I upgraded, I noticed there were two wheels attached to the front of the deck that seemed to run across the floor while I mowed. So, I did what most people don’t like to do, and I studied the owner’s manual. Let me share with you what I discovered.
Should Mower Deck Wheels Touch the Ground? (The Short Answer)
The wheels attached to a lawn mower cutting deck are called anti-scalping wheels. They are designed to touch the ground periodically as the lawn mower runs over uneven ground. Anti-scalping wheels are not designed to be in constant contact with the ground. If the mower deck wheels are continually running on the ground, then they need to be adjusted.
What Are Mower Deck Wheels Even For?
Mower deck wheels, or anti-scalping wheels, are designed to prevent your lawn mower from scalping your lawn. You will usually find anti-scalping wheels on larger cutting decks as scalping becomes worse the bigger the deck gets.
These wheels sit below the cutting deck and limit how close the cutting blade can get to the ground. If you run over a bump in the lawn, you’ll notice that your lawn mower can and probably will cut much lower. This is what you call scalping. So, when you set the wheels at the desired height, it stops scalping.
What Can Happen If Your Mower Deck Wheels Do Touch the Ground?
If your mower deck wheels are touching the ground, they are actually doing their job and preventing the deck from getting too low to the grass. But this shouldn’t be happening all the time. Touching the grass is ok, but not running along the dirt. Here are a few problems you might come across if this happens too much.
Damage to the Wheels
If you have a completely flat lawn without any bumps whatsoever, then your deck wheels should ideally never come into contact with the ground. Now, having a perfectly flat lawn is going to be nearly impossible unless you own a football field.
On a pretty flat lawn, your anti-scalping wheels will touch the ground from time to time. This means the wheels should only get very light use. Now, lawn mowers use solid, hard-plastic wheels with bearings designed for light use.
So, if you’re running over the ground pretty much all the time, then the bearings are going to wear out very quickly, and the wheels will stop working.
Damage to the Deck
Once the bearings go out on anti-scalping wheels, you’ll start to see wear on the wheel’s mounting brackets. Without the bearings, the wheels will no longer be held in position and will be able to rub up against the deck.
I’ve seen a couple of mowers where the wheels had been allowed to run with bad bearings for such a long time that they actually wore through the mounting brackets and fell off.
Unbalance the Deck
If your deck wheels are running too low, then they will put a lot of stress on the cutting deck as the wheels are feeling every little bump. If you take a look at your lawn mower’s deck, you’ll see that it hangs off the mower, and the tires of the mower take the impact.
So, if the wheels are constantly running over the ground, the deck will be directly subjected to the impact of each bump. The biggest problem this causes is that it puts stress on your deck’s mounting system and adjustment. It won’t be long before you start to notice your lawn isn’t being cut evenly anymore.
Digging into the Grass
Again, if you closely inspect the anti-scalping wheels, you will notice that they are fixed so that they can only rotate forward and backward. This is fine when your lawn mower is moving in a straight line. But, when you turn, if your deck wheels are set too low, they will begin to drag.
I’ve seen this happening on a few lawns where the lawn mower digs ruts into the grass. This is because the anti-scalping wheel can’t turn in a sideways direction.
What if the Deck Wheels Never Touch the Ground?
It’s pretty common that deck wheels are installed by the factory at their highest setting. This means that the deck wheels might not ever touch the ground, even on a bumpy lawn. Well, when the anti-scalping wheels are at the highest setting, you’ll probably get a bunch of scalped areas in your lawn.
Also, you could find that the front of your cutting deck digs into the ground in particularly bad areas or when you transition to a different angle of your lawn. I find that the bottom of a slope is the worst place for the cutting deck to dig into the lawn.
What Height Should Mower Deck Wheels Be Set At?
So, should mower deck wheels touch the ground? Yes, but only to prevent scalping, and definitely not all the time. Therefore, if your deck wheels are still set to a super high factory setting, or they are running on the ground too often, you’ll need to make an adjustment.
So, let’s look at what mower deck wheels should be set to and how to make an adjustment.
Working Out the Lowest You Want to Mow
The first thing you want to figure out is how low you want your lawn to be cut. I have my lawn mowers adjustment lever set to cut my lawn at 3 ½ inches. Now, I do make adjustments to the cutting height to occasionally cut higher, but the lowest is always 3 ½ inches.
Once you have decided on the height of your lowest mowing height, you can move on to adjusting the deck wheels.
Park on Level Ground
Next, you want to park your lawn mower on a level, hard surface. I usually use my garage floor as this is the most level surface on my property.
Check the Tires are Correctly Inflated
Then, you’ll need to make sure your ride-on lawn mower’s tires or your zero-turn mower’s tires are correctly inflated. This is so that when you are adjusting your anti-scalping wheels, you know you are making adjustments to a lawn mower that is level.
Check the Deck is Perfectly Level
Now that you’re on level ground and have properly inflated tires, you can move on to checking that your cutting deck is level. This is where you measure the outer blade tips of each blade and make sure they match.
Then, you measure the tips from back to front and make sure they are both set within range. Again, this is important so that your adjustment to the anti-scalping wheels is accurate.
Adjusting the Anti-scalping Wheels
Finally, it’s time to adjust the deck wheels. So, what you are aiming to do is adjust the wheels so they are approximately ¼ – ½ inches off of the ground when the deck is adjusted to your desired cutting height. In my case, I would drop the deck to 3 ½ inches and then make an adjustment.
Set your deck at the cutting height you want, then take a look at the deck wheels. If your wheels are always touching the ground when you mow, then you’ll probably find the wheels are already touching the ground. Therefore, lift the deck back up, and grab a socket wrench and a wrench.
Next, use your tools to remove the center nut and bolt from each of your deck wheels and remove each wheel. Now, you’ll see that there are a few holes in the wheel mounting brackets you can use to mount the wheel at different heights. You need these in a second.
Lower your deck again so your deck is positioned without any obstruction of the wheels to the height you want your lowest cut to be. Next, take one of the deck wheels and position it in its mounting bracket and find the closest bolt hole that allows the wheel to be mounted ¼ – ½ inch off the ground.
Once you have figured out the hole, you can reinstall the deck wheel. Finally, install all the other anti-scalping wheels to the same height. This is all you need to do to have your deck wheels set correctly so they can effectively prevent scalping.
Tools Adjust the Deck Wheels “Anti-Scalping Wheel Adjustment”
- Tape Measure
- Tire Inflator
- Socket Wrench Set
- Wrench Set
Leave a Reply