How To Measure A Mower Belt

How To Measure A Mower Belt: Step-By-Step Guideline

3 minutes

If we use a lawnmower regularly, the lawn mower’s belt stretches and becomes loose over time, which causes the belt to break. If this happens, you will need to change the belt, and to do this, knowing the measurement of the belt is essential.

You might also be wondering about changing the mower’s belt, or want to know how to measure a mower belt. 

Keep reading to find out all of this and more!

How To Measure A Mower Belt: Your Ultimate Guide

During the summer season, with excessive use of a lawn mower, the belt tends to break or get damaged. There are two different methods to measure the belt before replacing it. We will discuss both but first, let me tell you about the belt.

So, let’s get started!

What Is The Mower Belt?

A lawn mower belt is a loop that is made of flexible material. It is typically used to connect different mechanically parallel and rotating shafts together. 

A mower belt creates and controls the movement of different parts inside the deck. This belt helps to control the movement of the mower to a particular direction and ensure efficient transmission of the mower.

How To Measure Lawn Mower’s Belt

As already mentioned above, there are two methods of measuring the belt.

Method 1: Measure The Belt Based On The Distance To The Spindle Pulley

Required tools and materials

Measuring Process:

To begin, open the inside deck of the lawn mower by using a screwdriver or wrench. The belts and deck rod will be visible within the mower.

Now, check the spindle pulleys inside the lawnmower. You’ll notice multiple pulleys inside the deck. Each pulley has a particular purpose.

The mower blade is held in place by the two largest pulleys. Tensioner pulleys or Idler are the tiny pulleys that assist in routing the belt in the proper direction. 

Every pulley is connected through the belt. Hence, the lawn mower belt moves from one pulley to the next when it starts mowing. 

Now, by using a measuring tape, measure the distance of one spindle pulley to another spindle pulley. For instance, measure the distance between spindle pulley 1 and 2, then spindle pulley 2 and 3. 

Lastly, add all the measurements together. The total sum of the numbers will be the measurement of the belt on your lawn mower. 

Method 2: Measure The Lawn Mower’s Belt By Using A Measuring Tape

Required tools and materials

Measuring Process:

If the belt has worn out but has not broken on its own, cut through it by using a utility knife. You won’t need to cut the belt if it is already broken.

Stretch the belt on a level surface, such as a garage floor or table, with the flat side facing down. Weigh down both ends of the belt with something heavy, in case they try to roll up. 

Now, position one end of the flexible measuring tape at the one end of the belt and then extend the tape across the other end of the belt. 

Calculate the total length of the belt using the tape measurer. You can also measure the width of the belt by using the tape measure.

Thus you can easily take the measurement of the mower’s belt. 

How To Protect The Belt From Damage

  • Always examine the edges of the mower’s blades and whether they are affecting the belt. If the blades can touch the belt, they can easily damage the belt. 
  • Examine the mower’s shafts and discs for any mechanical flaws.
  • Keep your lawn mower’s deck clean to avoid getting tall shrubs or grass stuck in it.
  • Use oil lubricant to keep everything smooth. 


Hopefully, you have found this article on ‘how to measure a mower belt’ helpful. 

On a final note, you could also take the mower’s belt to the supply store to get the perfect replacement.  

Todd L Miles
Lawn Mowers Enthusiast
I started "Landscape and Lawns Care" to provide clients with lawn care with better service, better products and, most importantly, better ethics. My promise to every customer is to give the greenest grass possible while controlling weeds, insects, and diseases! The most important thing is that I strive to always do the right thing for you, your lawn and your wallet!