Riding mowers are a bit different than your regular lawnmower. With care and caution, you can change the blades on your riding mower without having to go to a professional. Doing so will increase your lawn mower’s efficiency and speed, as well as extend the overall life of your grass-cutting machine.
Steps to Change Riding Lawn Mower Blades
Before changing your lawnmower blades, are you sure that’s the issue? You may want to troubleshoot your lawnmower for other problems if you’re not sure.
Also, you may not need to replace the blades but sharpen them instead. If you check the blades and find they are simply a bit dull or worn, sharpening them can increase your lawn mower’s efficiency dramatically.
However, if your riding lawn mower’s blades are bent, cracked, or otherwise damaged beyond repair, it’s time to replace them. Here are some simple steps to get this done fast:
What You Need to Change Blades on Riding Mowers
Check your owner’s manual first for instructions on changing blades and the tools needed. Your riding mower may have different parts.
- Correct size wrench (check owner’s manual)
- Cheater pipe wrench (optional)
- Lift or cement blocks to raise the riding mower
- Compatible, replacement riding mower blades
Step 1: Get Started on the Right Work Surface
You don’t want to do this in the middle of the yard. Instead, you should pick a garage or flat surface to work on your riding mower.
Next, turn off your mower, lock the brakes, and put stoppers on the wheels. It would help if you also disconnected the spark plugs. After the riding mower is completely cool, you can work on the blades.
Step 2: Access the Blades
The easiest way to access the blades is to raise the mower deck to the top setting. You can quickly get under the mower now and see the blades. You should have enough room to work with your tools.
You may want to use a tractor lift or cement blocks to ensure that the mower is safely secured above you. Otherwise, this massive piece of equipment could fall on you while you work. Check that it’s wholly immobile and stuck in place before working underneath.
Step 3: Remove the Mandrel Nut or Bolt
On the underside of your lawnmower, you should find the mandrel nut or bolt. You’ll need the right sized wrench to remove this nut. It’s also recommended that you use a cheater pipe to prevent the blades from turning as you remove the nut.
You’ll turn the nut counterclockwise and gently remove it from the shaft. The blades can then be easily removed. Some blades may be sealed and need a little more elbow grease to remove.
Step 4: Replace the Blade
There are a variety of blades out there that could match your riding mower. You should check your owner’s manual to find your model and compatible blades or bring the blade with you to a hardware store to match the same type and size.
To install the new blade, position the blade right side up, and push onto the spline or blade shaft all the way. Tighten the mandrel nuts to secure the new blade.
Tips for Riding Lawn Mower Blade Repairs
While replacing your blades is a good idea if they are cracked or bent, it may not be the issue preventing your mower from working correctly. Several other parts may appear to be a lousy blade when it’s a problem with a drive belt.
Here are a few different reasons that your riding mower’s blades may not be working correctly:
- Depending on your mower model, you may need to remove the mower deck before replacing the blades
- Check the deck belt for breaks, cracks, and other damage if blades still won’t work
- The deck belt is located typically under the seat, but check your owner’s manual for exact location
- Ensure that the deck belt engine to see if any other belts have been damaged, if blades still will not turn
- Inspect the blade clutch, which stops the mower blades from spinning; it’s located under the engine and connected to the crankshaft
- If blades still not running correctly, check that the safety switch is working correctly.
- A bad safety switch can stop the blades from turning; these are attached to the clutch or brake, or you may find it on the operator’s seat.
Still not sure if it was your mower’s blades or something else? We offer a few different guides, including a troubleshooting mower guide, to help with these issues. You can also send us your questions about riding mowers for specific help with your riding mower model.