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How to Tighten Drive Belt on Craftsman Lawn Mower

Have you ever noticed your Craftsman lawnmower not mowing smoothly and leaving grass areas uncut? It’s practically possible that the issue is a loose drive belt. But, Luckily, Tightening a belt is not as difficult as you might think. A few kinds of stuff are all you’ll need to make the adjustment.

If you’ve never repaired your Craftsman lawnmower before, then don’t worry. Here are detailed instructions for tightening the drive belt on a Craftsman lawnmower.

Some signs or symptoms

To begin, you must understand when the drive belt becomes damaged and whether or not the drive belt is fit for mowing. I’ll try to demonstrate some signs or symptoms that will alert you to tighten the drive belt.

How to Tighten Drive Belt on Craftsman Lawn Mower

Loosens up

Is your craftsman lawn mower stuck in half or at the start of the mowing process? Maybe the drive belt has become loose. It lacks sufficient power to continue operating continuously. As a result, it loosens up half of the process.

Slows down

The most typical symptom of a damaged drive belt is that the lawn mower suddenly slows down. Mowing grass becomes more complicated and hard as a result of this.


An engine that grumbles excessively is a sure sign of a damaged drive belt. It may be hard to operate the lawnmower without earbuds due to excessive loudness. 

If you faced any of the symptoms, my advice will assist you in resolving your issue. So, let’s get started on tightening a drive belt on a Craftsman lawnmower step by step.

Tools you must need

  • A screwdriver
  • A socket range
  • A wooden black (Optional)
  • A lifting jack
  • A hard-wire cleaning brush
  • A new drive belt
  • A plastic sheet or trash bag
  • A pair of work gloves
Tools you must need

Find the ideal location

You’ll need to have enough space to work comfortably. As a result, park the mower on an even surface before going on to the next step.

For example, a garage or driveway would be great. Turn off the engine when you’ve parked the mower. You may also use a socket wrench to remove the key, take out the spark plug, and disengage the blades for extra safety.

Evaluate the current test drive

An adjustable wrench is the most convenient way to check the drive belt tension. To adjust the drive belt of a lawnmower, loosen the set screw and spin the wrench counter-clockwise.

On larger diameter belts, use a torque wrench. However, Many latest belt tension systems are specifically built for smaller diameters and ground stakes.

Blade tension is important to consider when using a torque wrench, as it can make or break a lawnmower operation.

Take off the mower deck

To reach the drive belt, remove the mower deck in the next step. Remove all cotter pins that connected the deck to the mower with the aid of a plier. The clutch rod pins, the anti-sway bar, and the two suspension arms in the center of the deck all fall under this category.

Before going on to the next stage, remove the dust and dirt that has gathered on the shaft and engine using a wire brush while you’re at it.

Take off the mower deck

Check the parts of the mower deck

As we can see, the driving belt is loosening, and we’ll need to repair this for the mower deck components. To do so, pull back your blade engagement lever and lower the deck as much as possible. After that, look through the following factors:


Check to see whether your drive belt is in good condition and doesn’t have any cracks or pieces missing. You should replace it immediately if it seems to be damaged.


 The swingarm is a component on the deck that connects the springs and holds a pulley. At one end, the arm is pivoted, while the other end is free to spin. Ensure that the arm may rotate freely. If it isn’t, lubricate the pivoted end, which may have become stuck.

Push the lever again to engage the blades when the above components are working properly.


A spring is attached to the cable that runs from the lever. Check to verify if the spring is fully stretched or if it is loose. At the same time, feel your belt to see whether it’s loose. If so, we’ll go to the next step, which is to Adjust the cable to tighten the belt 

Tighten the belt by adjusting the cable

If the belt tension has tightened after a few usages, the tension cable is likely damaged. If the belt is damaged, you will need to replace it. Replace the worn-out belt with a new one made of high-quality materials.

To maintain the drive belt on your Craftsman lawn mower tight, use the blade lever to apply pressure to the belt, which will tighten the belt. Anyone who wishes to operate with a belt must first understand how to properly control it.

It’s worth remembering that this isn’t just about feeling good about yourself though that helps! It’s also important to understand how the belt reacts in various situations.

Tighten the belt by adjusting the cable

Final Testing period

After you’ve put the mower back in position, you’ll need to test it. Connect the spark plug, fill the gas tank, and turn on the device as usual to do this. Test it out by driving it around for a bit.

If everything goes well, give yourself a pat on the back since you’ve finally tightened the belt!


1. How do you sharpen lawn mower blades without removing them?

To begin, disconnect the mower’s plug and the gas tank’s cover. Place a wooden block under the blade of the lawnmower and tilt it. Remove any rust and dirt from the blade with a steel wire brush.

2. Do lawnmower belts shrink?

Lawnmower belts mostly shrink when they are not used in the proper size. Belt shrinkage can be caused by a long or short belt. In addition, when utilized as automobile belts, some belts may shrink depending on their manufacture and stickiness.

3. How often should you replace the lawn mower belt?

A mower belt isn’t meant to last for a specific period of time; however greater mower use reduces the duration between belt replacements. Simply said, the more you use something, the more worn it becomes. Lawnmower belts can also be prematurely broken due to defective belts or mechanical problems such as a stuck pulley.

Last words

Lawnmower belt maintenance is one of the most common problems, especially if the mower hasn’t been properly maintained in the past. We recommend cleaning your lawnmower on a regular basis and thoroughly inspecting the functioning components of the mower deck to ensure they are in good working condition. Furthermore, when replacing a belt, you should always refer to the owner’s handbook. You can also read our review about the best commercial zero-turn mowers.

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