Maintaining your riding lawn mower is essential for keeping your lawn looking its best. One important part of this maintenance is regularly changing the mower blades. Sharp blades cut the grass cleanly, preventing ragged edges and promoting healthy growth. Dull or damaged blades can tear the grass, leaving it more susceptible to disease and pests.
Changing the blades on your riding lawn mower is a relatively simple task that can be done in a few minutes. However, it is important to take safety precautions and to follow the manufacturer’s instructions carefully. In this article, we will provide step-by-step instructions on how to change the blades on your riding lawn mower. Additionally, we will provide some tips on how to keep your mower blades sharp and in good condition.
Before you begin, it is important to gather the necessary tools and materials. You will need a new set of mower blades, a wrench, and a socket set. You may also want to wear gloves to protect your hands. Once you have gathered your tools and materials, you are ready to begin changing the blades on your riding lawn mower.
Safety Precautions
Working on a riding lawn mower requires caution and meticulous attention to safety protocols. Failure to adhere to these precautions can lead to serious injuries or even fatalities. Before attempting any maintenance or repairs, it is imperative to take the following measures:
1. Disconnect the Spark Plug:
This is the most crucial safety step to prevent accidental starting of the mower while you are working. Locate the spark plug on the engine and disconnect the wire leading to it. Make sure the wire is securely out of the way to prevent any accidental contact.
Safety Precaution | Reason |
---|---|
Wear Safety Gear | Protect yourself from flying debris and potential cuts or abrasions. |
Read the Owner’s Manual | Ensure proper understanding of maintenance procedures. |
Inspect the Mower | Check for any damage or loose parts that may affect safety. |
Gathering Necessary Tools
Before tackling the task of changing your riding lawn mower blades, it’s crucial to gather the necessary tools. These include:
Wrench or Socket Set
You’ll need a wrench or socket set to remove and tighten the nuts that secure the blades to the mower deck. Choose one with a suitable size for the bolts on your mower.
New Blades
Replace dull or damaged blades with new ones that match your mower’s make and model. Inspect the old blades carefully to determine if you need to replace both or just one.
Mulching Kit (Optional)
If you’re converting your mower into a mulching mower, you’ll need a mulching kit that consists of mulching blades and a mulch plug. This kit allows the cut grass to be finely chopped and evenly distributed over the lawn.
Safety Gear
For safety, wear gloves to protect your hands from sharp edges and eye protection to guard against flying debris. Additionally, disconnect the spark plug wire to prevent the mower from starting accidentally.
Additional Tools
In some cases, you might also need a blade wrench, a torque wrench, or a hammer and chisel to remove stubborn bolts. Having these additional tools on hand will ensure you’re prepared for any challenges you encounter during the blade-changing process.
Locate the Blade Bolts
To locate the blade bolts on your riding lawn mower, you’ll need to start by disengaging the blade and parking the mower on a stable and level surface. Once the mower is secure, engage the parking brake to prevent it from moving.
Next, tilt the mower deck into the service position. This will vary depending on the make and model of your mower, but typically involves pulling a lever or releasing a latch located near the front of the mower deck. Once the deck is tilted, you’ll be able to access the underside of the mower deck and locate the blade bolts.
The blade bolts are typically located near the center of the blade, and they may be covered by a protective shield or guard. Remove the guard or shield to expose the blade bolts. The blade bolts may be either hex bolts or carriage bolts, and they will typically be 5/8 inch or 3/4 inch in diameter. Use the appropriate wrench or socket to loosen the blade bolts. Be careful not to overtighten the blade bolts when you reinstall them, as this can damage the blade or the mower deck.
Secure the Mower Deck
Before starting any repairs or maintenance, it’s crucial to secure the mower deck to prevent it from falling and injuring you or others.
Step 1: Park the Mower on a Level Surface
Park the mower on a flat, stable surface and engage the parking brake.
Step 2: Locate the Deck Support Pins
Underneath the mower deck, locate the deck support pins or brackets. These pins are typically located at the front and rear of the deck.
Step 3: Insert the Support Pins
Insert the support pins into the corresponding holes on the mower’s frame. Ensure they are fully inserted and secure.
Step 4: Jack Up the Deck
If the support pins are not sufficient to provide adequate clearance, use a jack to raise the deck slightly. Place the jack under the center of the deck and pump it until it lifts the deck off the ground by a few inches.
Step 5: Use Safety Stands
For added safety, place safety stands under the lifted deck to support it and prevent accidental falls. Safety stands are typically made of wood or metal and can be purchased at most hardware stores.
Step 6: Secure the Stands
Adjust the safety stands to ensure they are stable and positioned correctly to support the weight of the deck.
Remove the Spark Plug
Safety First
Before you start any work on your riding lawn mower, it’s crucial to take safety precautions. Disconnecting the spark plug prevents the engine from starting accidentally while you’re working on it.
Locating the Spark Plug
The spark plug is usually situated on top of the engine, near the cylinder head. It’s typically covered by a rubber boot or cap.
Removing the Boot
Grasp the spark plug boot firmly and pull it straight up to detach it from the plug. Be careful not to damage the boot or wire.
Unscrewing the Spark Plug
Using a spark plug socket or wrench, turn the spark plug counterclockwise to loosen it. Remove the plug by hand once it’s loose enough.
Inspecting the Spark Plug
Take a moment to inspect the spark plug. Check the electrodes for wear or damage. If the plug is excessively worn or damaged, it should be replaced.
Spark Plug Condition | Action |
---|---|
Electrodes are worn or damaged | Replace the spark plug |
Electrodes are clean and in good condition | Reinstall the spark plug |
Detach the Blade Bolts
Once you have removed the spark plug wire, it’s time to detach the blade bolts. Use the wrench or socket that came with your lawn mower to loosen the bolts. Some models may have multiple bolts per blade, while others may only have one. Be sure to remove all of the bolts before attempting to remove the blade.
When loosening the blade bolts, be sure to hold the blade steady with one hand. This will prevent the blade from spinning and potentially causing injury. Once the bolts are loose, carefully remove them and set them aside in a safe place.
Bolt Size | Common Mower Models |
---|---|
5/16 inch | Craftsman, Husqvarna, Toro |
3/8 inch | John Deere, Cub Cadet, Simplicity |
1/2 inch | Husqvarna (large models), Scag |
Slide Out the Old Blades
To safely remove the old blades, follow these steps:
1. **Safety First:**
Wear gloves and safety glasses to protect yourself from sharp blades.
2. **Park the Mower on a Level Surface:**
Park the mower on a stable surface to prevent it from rolling while working.
3. **Engage the Parking Brake:**
Set the parking brake to secure the mower and prevent it from moving accidentally.
4. **Locate the Blade Bolts:**
Identify the bolts that hold the blades in place. They are typically located on the underside of the deck.
5. **Loosen the Bolts:**
Use a socket wrench or crescent wrench to carefully loosen the blade bolts. Avoid overtightening or stripping the bolts.
6. **Remove the Blades:**
Once the bolts are loose, slide the blades out from under the deck and remove them completely.
7. **Inspect the Blades:**
Examine the old blades for any damage, such as cracks, bends, or nicks. If the blades are worn or damaged, they should be replaced with new ones.
Blade Condition | Action |
---|---|
Minor Nicks or Bends | Sharpen or flatten the blades |
Major Damage | Replace the blades |
Align and Install the New Blades
Once you have the new blades, it’s time to align and install them correctly. Here’s a detailed step-by-step guide:
Step 1: Line up the Blades’ Mounting Holes
Align the mounting holes on the new blades with the holes on the blade spindle. Ensure the blades are positioned correctly, usually with the cutting edge facing outward.
Step 2: Insert the Blade Bolts
Insert the blade bolts through the mounting holes and hand-tighten them as much as possible.
Step 3: Tighten the Blade Bolts (Phase 1)
Using a torque wrench, tighten each blade bolt to the manufacturer’s torque specifications. Refer to the table below for common torque values.
Blade Size (Inches) | Torque (Pound-Feet) |
---|---|
17-19 | 30-35 |
20-22 | 35-40 |
23-25 | 40-45 |
Step 4: Turn the Blades 180 Degrees
Rotate the blades 180 degrees so that the star-shaped holes align with the grooves on the underside of the deck.
Step 5: Insert the Mulching Plugs
Some mowers come with mulching plugs that you can insert into the star-shaped holes to prevent grass clippings from being discharged from the side.
Step 6: Tighten the Blade Bolts (Phase 2)
Finally, using the torque wrench, fully tighten the blade bolts to the second torque specification provided by the manufacturer.
Step 7: Install the Blade Washers
If your mower uses blade washers, place them over the blade bolts and tighten the nuts securely.
Step 8: Reinstall the Deck
Carefully lift the deck back onto the frame and secure it with the bolts or pins. Ensure the drive belt is properly aligned before reinstalling the belt guard.
Tighten the Blade Bolts
9. Tighten the Blade Bolts Securely
The final step is to tighten the blade bolts securely. Use a torque wrench to ensure they are tightened to the manufacturer’s specifications, typically between 60 and 90 foot-pounds.
Using a Torque Wrench:
a) Position the torque wrench onto the blade bolt.
b) Set the torque to the recommended setting.
c) Gradually apply pressure until the wrench clicks, indicating the correct torque has been reached.
Caution:
Using an incorrect torque can damage the bolts, blades, or mower deck. Overtightening can strip the threads or damage the blades, while undertightening can cause the blades to become loose and hazardous.
Tips:
- Use a sharp, clean blade for optimal cutting performance.
- Inspect all blades regularly for damage or wear.
- Consider using anti-seize lubricant on the blade bolts to prevent corrosion and make future blade changes easier.
Reinstall the Spark Plug
Once you have checked the gap and cleaned the spark plug, it’s time to reinstall it. Carefully thread the spark plug back into the cylinder head by hand until it is finger-tight. Then, use a spark plug wrench to tighten the plug an additional 1/4 to 1/2 turn. Be careful not to overtighten the spark plug, as this can damage the threads in the cylinder head.
Tightening Torque
The correct tightening torque for a spark plug varies depending on the make and model of your riding lawn mower. Refer to your owner’s manual for the specific torque value. As a general rule, most spark plugs should be tightened to between 15 and 25 foot-pounds of torque.
Types of Spark Plug Wrenches
There are two main types of spark plug wrenches: socket wrenches and T-handle wrenches. Socket wrenches are typically used with a ratchet or breaker bar, while T-handle wrenches are designed to be used by hand. Both types of wrenches have their own advantages and disadvantages. Socket wrenches are more versatile, but T-handle wrenches are more compact and easier to use in tight spaces.
Type of Spark Plug Wrench | Advantages | Disadvantages |
---|---|---|
Socket Wrench | -Versatile | -Requires a ratchet or breaker bar |
T-Handle Wrench | -Compact | -Less versatile |
How to Change Riding Lawn Mower Blades
Changing the blades on your riding lawn mower is an important part of maintaining your equipment. Dull or damaged blades can make it difficult to mow your lawn evenly and efficiently. Luckily, changing the blades is a relatively simple and straightforward process.
To get started, you will need a few tools. These include a socket wrench or adjustable wrench, a pair of pliers, and a safety glasses. You should also disconnect the spark plug wire from the spark plug before beginning any work on the mower.
Once you have your tools and have disconnected the spark plug wire, you can begin the process of changing the blades. First, locate the deck of the mower. This is usually a metal or plastic housing that encloses the blades.
Next, find the blade bolts. These are usually located on the top of the deck. Use the socket wrench or adjustable wrench to loosen the bolts. Be careful not to overtighten the bolts when you are reassembling the mower.
Once the bolts are loose, you can remove the old blades. Be careful not to cut yourself on the blades. If the blades are stuck, you can use a pair of pliers to carefully pry them loose.
Now that the old blades are removed, you can install the new blades. Make sure that the new blades are facing the correct direction. The blades should be installed with the cutting edge facing down.
Once the new blades are installed, you can tighten the blade bolts. Again, be careful not to overtighten the bolts. Connect the spark plug wire to the spark plug and you are finished.
People Also Ask About How to Change Riding Lawn Mower Blades
How often should I change my riding lawn mower blades?
You should change the blades on your riding lawn mower every 25-50 hours of use. If you mow your lawn frequently, you may need to change the blades more often.
What are the signs that my riding lawn mower blades need to be changed?
There are several signs that your riding lawn mower blades need to be changed. These include:
- The blades are dull or damaged.
- The lawn is not being cut evenly.
- The mower is making a strange noise.
- The mower is not cutting as well as it used to.
Can I change the blades on my riding lawn mower myself?
Yes, you can change the blades on your riding lawn mower yourself. However, it is important to follow the safety instructions carefully. If you are not comfortable changing the blades yourself, you can take the mower to a qualified mechanic.