Have you found yourself asking “why does my lawnmower belt keep coming off?” There are a lot of problems that can happen with your lawnmower, and a loose or broken belt are just a couple of them. This is aggravating, but it can be more than just an inconvenience. This can be a legitimate safety hazard and you need to take this situation seriously. Depending on the specific make and model of your lawnmower, there may be different solutions.
The belt is an important part of your lawnmower because it allows the mower to cut the grass. If you are having problems, you should first do a safety check, then diagnose what is going on. Some of these problems can include issues with the mounting system, a damaged belt, debris interference, or other damaged parts. If you are still having problems, you might need to remove and/or replace the belt.
Why is the Belt Important?
The belt is an important part of your lawn mower because it lets the blades cut the grass. If the belt is worn, the blades won’t spin fast enough to cut your grass. If the belt is broken the lawnmower won’t work at all. A belt that falls off will obviously prevent the lawnmower from working, but even worse, this can also be a safety hazard.
Performing a Quick Safety Check
Before you try to diagnose the problem, it’s important to conduct a safety check so that you don’t lose a hand when the lawnmower suddenly starts up again. Put on gloves and goggles and take out the spark plug before grounding it against the engine. If you do this, the mower won’t start up again while you are working and remove your fingers.
What Are Some Common Problems?
This issue can be incredibly annoying, but easy to fix with a simple diagnosis. Here are a few of the more common problems that might make the belt come off of your lawnmower.
1. Mounting System is Out of Place
One of the most common problems that can cause the belt to come off of your lawn mower is that the mounting system might be off balance. This can affect how evenly your mowing deck hangs, which can cause issues, forcing the belt to come flying off of the lawn mower. It is also a good idea to check for missing parts, such as clip pins that are not securely in place, and a draft rod that isn’t securely attached to the front axle. If all of your equipment is in place, you probably have other problems that you need to check out.
2. Cracked or Loose Belt
Another common problem is that the belt itself might be damaged. Even if it doesn’t fall off, a damaged belt can be dangerous. A loose belt can slip and the friction can cause a fire in the engine. If the belt breaks while the engine is running, it can fly off at a high speed. As part of your safety check, you should look for cracks, fraying, or signs of a loose or separated belt. Replace the belt if you see any of these signs.
3. Damage Due to Neglect
There are several other parts of your mower that could be damaged, causing your belt to come off. If you do not keep the drive and idler pulleys clean and functional, they can cause the belt to come off. Check to see if the blades are spinning correctly. Also, make sure that your mower deck is slanted slightly forward. If the angle is off, this can also cause the belt to come off.
4. Debris Build Up
If you allow debris to build up in your lawnmower, this can interfere with its functionality, and cause the belt to come off. Make sure that there are no items such as grass, sticks, acorns, rocks, soil, or any other debris that is stuck anywhere on the drive belt. Not only can this cause the belt to slip, fall off, or function badly, this can also be a fire hazard. Make sure that you remove any debris, and then thoroughly clean the belt with a fresh cloth.
Removing the Belt
If all else fails, you might have to replace the belt on your lawnmower. This is inconvenient to say the least, but it might be your only remaining option. If you need to replace the belt, or install a new one, then these are the steps that you should follow. Before you can replace the belt, first you have to remove the old one.
If you have to do this, turn off the mower and make sure you have set or parked it on an even surface. Wait until the engine has cooled down. Then, remove the ignition key and make sure you disconnect the spark plug wires. If your lawnmower has two cylinders, make sure that you disconnect both spark plug wires. Disengage the PTO lever. If you are using a riding mower, make sure that you are using the parking brake.
Make sure that you put the deck height lever at the lowest position you can, and then disable the blades. Removing the belt from the engine’s pulley and the belt keepers is the next step. You should repeat this process on the other side of the deck. Make sure that you disconnect the suspension arms and rear deck brackets.
Make sure that you pull the deck out enough that you are able to reach the blade drive belt.
Don’t use the lever until you have reinstalled the mower deck, because there is more tension on the lever than there normally is.
Release the belt from the pulleys and take it off of the mower deck. If the belt is broken, you should check your owner’s manual for guidance. If the belt is not broken, then you should check the direction that the belt runs in so that you know how to put it back on correctly.
Replacing the Belt
You should start by looping the belt around the mandrel pulleys. Then, you should route the belt around the belt keepers and the idler pulleys. Check your owner’s manual for specific instructions on how to do this, because this can vary from lawnmower to lawnmower.
After you replace the belt, you need to reinstall the mower deck. You should connect the lift link support to the deck and to the retaining clip. Then it’s time to reconnect the suspension arms and the deck brackets with the retaining clips and with the washers. Repeat this process with both the right and the left suspension arms.
Route the belt through the belt keepers and through the engine pulleys. Finally, connect the spark plug wires. If your engine has two cylinders, it is important to reconnect both spark plug wires.
Commonly Asked Questions (FAQ)
1. How long does a lawnmower belt last?
Lawnmower belts typically last 3-4 years. It also depends on weather conditions, weight distribution, and many other factors.
2. How much does it cost to replace a riding lawn mower belt?
The belt itself can cost anywhere from $10 to $35, but the total repair cost with labor included can be up to $90.
3. How many years does a lawn mower last?
The average life of a lawnmower is 8 to 10 years. However, if you use it often and don’t do proper routine maintenance, it will die much quicker.