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Tighten a Craftsman Riding LawnmowerDrive Belt: step by step

Notice a decline in your Craftsman riding lawnmower’s performance? It might be time to tighten the drive belt. Our comprehensive guide provides a step-by-step process, making the task straightforward and hassle-free.

Check the belt, swingarm, and spring for needed tightening. If the belt slips, loosen the bracket bolts and pull back to tighten the spring. Engage blades at full throttle to test tension. If the belt still slips, replacement may be needed. Re-adjust the bracket until the blades engage immediately when the throttle is engaged. Reconnect anything disconnected when finished.

Does your lawnmower seem to be lagging? A loose drive belt could be the culprit. Read on to learn how to tighten it and get your lawnmower running smoothly again.

Contents

Troubleshooting and Adjusting the Drive Belt on a Craftsman Riding Lawnmower, step-by-step:

The steps that need to be followed to fix the Craftsman lawnmower drive belt are mentioned below:

● Step 1: Test the current drive belt for operation:

Before we dig into it, we first need to see whether the current drive belt is loose and worth tightening. Most Craftsman models have a blade engagement lever next to the steering wheel. After the cutting deck is lowered to the ground, the lever engages the blades to make contact with the grass and perform their function.

Start your engine and push your throttle lever to the highest to see if your current drive belt is loose. Next, engage the cutting blades by making the lever upwards. Hearing the blades’ cutting sound right after you push the engagement lever indicates that the drive belt has the requisite tension and doesn’t need any adjustment.

If you notice that the blades aren’t cutting the grass after the very instant, you push the lever and give a whirring sound, your drive belt is slipping, thus pointing out the need for adjustment or replacement. This is where engine troubleshooting comes into play.

● Step 2: Inspect the mower deck components:

As we’ve seen, the drive belt is slipping; we need to troubleshoot this for the components on the mower deck. To do this, lower the deck as much as possible and pull back your blade engagement lever. Then, you need to inspect the following components:

Belt: Ensure your drive belt is intact and does not appear damaged with missing chunks and cracks. If it seems damaged, then you should replace it right away.

Swingarm: The swingarm is a component on the deck where the springs are connected and a pulley is mounted. The arm is pivoted at one end and free to rotate at the other. Make sure that the arm is free to rotate. If it is not, drop some oil or a lubricant at the pivoted end, which might have been jammed.

Over the years, I’ve seen that if the drive belt is not properly tightened, it can slip off the pulley system, causing the mower to malfunction. This is a risk that homeowners should be aware of

After the above components function correctly, push the lever again to engage the blades. If there’s still a wobbling sound or the blades are not engaging immediately, it might be worth checking if the belt is only an inch too loose. If so, further adjustments may be needed to make it work properly.

Remember, always reconnect anything disconnected when finished. This ensures the safety and efficiency of your lawnmower.

Spring: The cable from the lever is connected to a spring. Touch the spring to see if it’s wholly stretched or loose. Also, touch your belt simultaneously and notice if it appears open. If it does, we shall move on to the next step, adjusting the belt tension.

● Step 3: Tighten the belt by adjusting the cable:

After you’ve seen your belt loosened up, disengage the blade lever again. You would have noticed the wire that comes from the blade lever and is attached to the springs. On the deck, it is mounted on a bracket.

Loosen the bolts on the bracket and push it back in the direction away from the spring. You now feel that the spring is tightened up.

● Step 4: Test the belt for tension:

After the bracket has been pulled back, start your lawnmower engine at full throttle. Now, push the blade engagement lever upwards and immediately notice the blades’ cutting action. The belt tension is optimal if the blades begin cutting without delay. However, If the belt still seems loose enough, it indicates that this method didn’t add the required tension, and therefore, you should think about replacing the belt.

Related Questions:

1. How do you remove and replace the drive belt on a riding lawnmower?

In most cases, tightening the drive belt does not solve the problem, and you often need to replace it altogether with an identical one. The steps for doing that are listed below:

Step 1: Disconnect the spark plug

First, you should turn off the ignition switch and remove the key. Next, pull the mower hood upwards and disconnect the spark plug wire.

Step 2: Disassemble the mower deck

Next, you need to disconnect the entire mower deck from the main body of the lawnmower.

– Step 2.1: Lower the mower deck

As a first step, lower the mower deck on the ground to the lowest position and disengage the blades.

– Step 2.2: Roll the belt off

Roll the belt off the engine pulley and release the belt keepers.

– Step 2.3: Detach the deck

Now, you need to remove all the linkages that connect the mower deck to the upper portion from both sides of the mower deck. To do this, remove the retaining pins and washer supports from the lift link, suspension arm, and rear end bracket on both the left and sides of the mower deck. The deck should now be detached completely.

If a homeowner is not comfortable tightening the drive belt themselves, I advise them to look for a service that has certified technicians, offers a warranty on their work, and has positive customer reviews

Step 3: Pull out the old belt

– Step 3.1: Take a picture

Note the routing of the blade belt on the mower deck. We recommend taking a picture to record the layout.

– Step 3.2: Remove the old belt

You might see three pulleys on the deck: one idler pulley, belt keepers, and two mandrel pulleys. Remove the old drive belt from the three pulleys.

Step 4: Install the new belt

Loop the new drive belt around the mandrel pulleys and pass it around the idler pulley through the belt keeper. Push the deck back under the mower.

Step 5: Reconnect the mower deck

Reconnect all the removed links, such as the lift links, suspension arms, and rear end bracket, and put them back onto the mower deck through the retaining pins and washers. Attach the belt back to the engine pulley.

With the mower deck assembled, reconnect the spark plug wire and insert the key in the switch. Start your mower and test the new belt for performance.

2. How long is the drive belt on a Craftsman riding lawnmower?

Drive belts transfer power from the engine pulley to movable parts in the mower, such as the blades. Craftsman lawnmower models consist of primary and secondary drive belts. Both belts range from 42-55 inches, depending on the model.

3. Why does the belt keep slipping off the lawnmower?

Your lawnmower’s drive belt may come off for various reasons. The exact reasons may depend on the design of your machine. However, some general reasons resulting from this problem are listed below:

– Damaged parts:

The drive belts and idler pulleys may affect the belt operation if they are not in working condition. Moreover, the swing arm should be able to rotate freely about its pivot. You need to check the mower deck’s adjustment as well. The deck’s front is generally lower 1/8 to 1/4 inches for normal conditions than the back. A pitch greater than this may cause the belt to keep slipping off.

– Debris Buildup:

The buildup of dirt and dust between the pulley and bracket may also reduce the friction attaching the belt to the pulley. Ensure no soil, grass, or sticks are found along the drive belt. This condition is quite imminent under rough operating conditions and low maintenance.

4. What are the two significant forms of drive belts used?

Transmission belts in machine design may be of the V-type or synchronous design. V-belts have a wedge-shaped cross-section. Friction is the only force keeping the belt attached. On the other hand, synchronous belts have a notched profile along their inner circumference, much like gears. They are generally mounted on gears and pinions and are used in timing operations.

Craftsman lawn tractor drive belt problems

If you want to replace the drive belt in your Craftsman lawn tractor but do not know how to, use the following tips:

  • Make a short video or take some pictures before removing the old belt.
  • Ensure that you use the correct belt. You can use the model number that is often under the seat for this.
  • Check the idler tensioner springs and brake arms and replace them when needed.

If the belt is damaged and gone, you can not find any information on how it should be routed. Use the following to understand where the belt needs to go:

  • Most Craftsman lawn tractors have up to 5 pulleys for the drive belt. They are easy to recognize.
  • The pulley underneath the engine is the drive pulley.
  • The pulley above the blades is easy to find. There can be one or two.
  • Generally, there is one spring-loaded pulley that keeps the belt under tension. Some models have no spring-loaded pulley but can be moved to tension the belt.
  • The remaining pulleys are fixed pullies that ensure the belt runs around other objects.

One unique tip I’ve learned over my 20 years of experience that isn’t commonly known is to mark the original position of the adjustment bracket before making any changes. This gives you a reference point if you need to revert

Craftsman Belt Keeps Coming Off or Breaking

Generally, a craftsman belt can keep coming off due to several reasons:

  • Check for debris: Check the underside of the lawnmower for any debris that may lead to the belt coming off.
  • Damaged or stretched belt: When the belt is damaged or stretched it will become loose. The tensioner will compensate for extra tension but quickly come off if it loosens too much. If the belt is damaged or stretched, it needs to be replaced. Clean the belt if it is slippery, maybe due to oil.
  • Damaged pulley bearings: If the bearings from one or more pulleys or the spindle housing get hurt, it can result in too much slack for the belt. Check the different pulleys for movement and replace the pulleys.
  • Belt keeper: If your Craftsman lawnmower uses a belt keeper next to the pulley, it may be bent or damaged. In that case, it may be why the belt keeps coming off.
  • Dirty pulleys: The different pulleys have a groove that keeps the belt in the correct location. If those grooves contain dirt, it can lead to the belt coming off. Check and clean the pulleys.
  • Tension spring: The belt is kept at the correct tension with the spring. If the spring gets worn out, it may not do its job correctly. Check the tension bracket and spring. If the spring and bracket look ok, check if they can move freely. If not, grease all the moving parts. Replace the spring and bracket if damaged or worn out too much.
  • Wrong belt: Ensure you use the correct belt for your Craftsman Lawnmower. The bad belt, even if it may look fine, can result in coming off quickly.

Remarks:

Lawnmower belt maintenance may be one of the most frequently occurring instances, mainly if the mower hasn’t been well maintained. We recommend cleaning your lawnmower occasionally and checking the mower deck’s working components to see if they are correctly working. Furthermore, you should always consult the owner’s manual when replacing the belt. It is better to exercise caution while making these replacements to avoid accidentally starting your lawnmower.

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  1. Manuel Fox says:

    I never knew how to check the tension on my lawnmower belt, thanks for the info!

    • Allard Vdhooft says:

      Glad to help, Manuel! If you have any other questions or need more information, feel free to ask. Happy mowing!

  2. Jack Walker says:

    How can I tell if the drive belt on my lawnmower is damaged and needs replacement?

    • Allard Vdhooft says:

      Hi Jack, check the belt, swingarm, and spring for tightening. Test by engaging blades at full throttle. If slipping persists, adjust the bracket. If necessary, consider replacing the belt. Hope this helps!

  3. Mildred Mckinney says:

    Thanks for the tips on adjusting the belt tension, my lawnmower is working much better now.

    • Allard Vdhooft says:

      Glad to hear your lawnmower is running better, Mildred! Let me know if you need any more tips in the future. Happy mowing!

  4. Sally James says:

    How often should I check the tension on my lawnmower’s drive belt?

    • Allard Vdhooft says:

      Make sure to check the tension on your lawnmower’s drive belt every season or sooner if needed. Tighten the belt to prevent slipping and maintain optimal performance.

  5. Jason Gray says:

    I followed these steps and my lawnmower is running great now, thank you!

    • Allard Vdhooft says:

      Glad to hear your lawnmower is running smoothly! If any more issues arise, feel free to reach out for further assistance. Happy mowing!

  6. Jack Fields says:

    Very informative, I was able to troubleshoot my lawnmower thanks to this guide.

    • Allard Vdhooft says:

      Glad to hear the guide helped. Let me know if you have any other questions or need further assistance!

  7. Logan Walters says:

    I appreciate the detailed explanation and step-by-step process.

    • Allard Vdhooft says:

      Thank you, Logan. We strive to make the process as easy as possible for our readers. Hope your lawnmower is up and running smoothly again!

  8. Marlene Wilson says:

    Can I use any type of belt to replace the drive belt on my lawnmower?

    • Allard Vdhooft says:

      Hi Marlene, it’s best to use the specific type of belt recommended for your lawnmower to ensure proper performance. Using the correct belt will help keep your lawnmower running smoothly.

  9. Ruby Gonzales says:

    Thank you for such a detailed and informative guide on tightening the drive belt on a lawnmower.

    • Allard Vdhooft says:

      Thank you, Ruby! I’m glad you found the guide helpful for tightening the drive belt on your lawnmower. Let me know if you need any more assistance.

  10. Duane Day says:

    Are there any preventive maintenance tips to avoid drive belt issues in lawnmowers?

    • Allard Vdhooft says:

      Simply make sure to regularly check the drive belt tension and adjust as needed to prevent issues in your lawnmower. This will help keep your machine running smoothly and efficiently.

  11. Thomas Cox says:

    Is it normal for a lawnmower belt to need adjustment frequently?

    • Allard Vdhooft says:

      Hi Thomas, it’s not normal for a lawnmower belt to need frequent adjustment. Make sure to check all components for proper tension and replace if needed. Hope this helps!

  12. Leslie Hernandez says:

    What tools do I need to adjust or replace the drive belt on a lawnmower?

    • Allard Vdhooft says:

      To adjust or replace the drive belt on your lawnmower, check the belt, spring, and swingarm for proper tightening. If slipping persists, consider replacement. Remember to reconnect all parts when finished.

  13. Louise Schmidt says:

    I had no idea there were so many components to check on a lawnmower, this was eye-opening.

    • Allard Vdhooft says:

      Thanks for reading! It’s definitely eye-opening to see all the components involved in lawnmower performance. Glad we could shed some light on the topic for you.

  14. Howard Austin says:

    What are the signs that I need to replace my lawnmower’s drive belt?

    • Allard Vdhooft says:

      Typically, a slipping belt and delayed blade engagement are signs that you need to replace your lawnmower’s drive belt for optimal performance.

  15. Walter Obrien says:

    What should I do if the drive belt on my lawnmower keeps slipping even after adjustment?

    • Allard Vdhooft says:

      Inspect the spring, belt, and swingarm for adjustment. Consider replacing the belt if needed. Readjust bracket until blades engage immediately to ensure proper tension. Reconnect all components when done.

  16. Mia Ellis says:

    I always struggled with my lawnmower belt, but this guide made it so clear.

    • Allard Vdhooft says:

      Thank you, Mia! I’m glad the guide helped you with your lawnmower belt. Let me know if you have any other questions or need more assistance.

  17. Katherine Willis says:

    I’m so glad I found this guide, it saved me a lot of time and money on repairs.

    • Allard Vdhooft says:

      Thank you for your feedback, Katherine! I’m glad the guide was helpful in saving you time and money on repairs. Let me know if you have any more questions.

  18. Cameron Perry says:

    This is so helpful, I had no idea how to tighten my lawnmower’s drive belt!

    • Allard Vdhooft says:

      Thanks, Cameron! I’m glad you found the guide helpful for tightening your lawnmower’s drive belt. If you have any more questions, feel free to reach out!

  19. Dennis Kelley says:

    Great guide, easy to follow and detailed steps.

    • Allard Vdhooft says:

      Thank you, Dennis! Glad to hear you found the guide helpful. Let me know if you have any other questions.

  20. Nellie Rodriquez says:

    Will tightening the drive belt improve the overall performance of my lawnmower?

    • Allard Vdhooft says:

      “Inspect and tighten the drive belt, spring, and swingarm for optimal performance. If slipping persists, consider replacement. Follow our guide for step-by-step instructions. Happy mowing!”

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