How to Change a Lawn Mower Belt

I think it’s Murphy’s Law that says something about the first lawn cutting event of the spring quickly fizzling into the first lawn mower repair event of the spring. In the current state of the economy, who can afford to take a broken lawn mower to a repair shop, or for that matter, buy a new one? The good news, in the case of a broken belt, you don’t have to. I’ve listed some steps below that should be able to point you in the right direction to repairing your broken belt, no matter what kind of lawn mower you have.

Step 1: Consult your user’s manual or Internet to determine what kind of belt you need and who sells them. It’s best to be armed with both the make and part number so that the clerk behind the counter has less of a chance to bring you the wrong part and save you the hassle of having to return it later.

Make sure of two very important things when you are purchasing your new lawn mower belt. First, buy a quality belt, even if it costs a little (or a lot) more. This will save you the aggravation of having to do this again in a month. Secondly, take the old belt with you. This way you can match the new belt to the old one and make sure that you have the right one.

Step 2: Check your user’s manual or Internet for a belt routing diagram. Depending on the model mower you have, the number of pulleys and other assorted hardware that you have to wrap that new belt around will vary. The proper installation of the belt will ensure that your mower will work when you are finished.

Step 3: Determine whether or not you will need to remove the mower deck. Once again, consult your manual or Internet instructions on whether or not this step must be performed. The good news is that there should be just a few well-placed Phillips screws holding it in place, though you may have to clean the crud out from under the deck to find them all.

Step 4: Remove any pieces of old belt remaining and install the new belt per the belt routing diagram.

Step 5: Replace the mower deck (if necessary)

Step 6: Compare what you see under your mower to the belt routing diagram and diagram of a properly operating mower. These images should match. If not, do NOT start the mower. Start over at step one.

Step 7: Right the mower and attempt to start

If the belt was installed correctly, your mower should be purring like a kitten and ready to begin work. If not, it’s probably not running at all or making obscene noises. If you are in the latter category, shut the mower down and begin again at step one.