If you have come this far, it means that you have tried to use your lawnmower in a failed way. A lawn mower can die from one moment to the next and there are many reasons for this. That’s why here you will find the main reasons and problems of a lawn mower and the best solutions to apply.
Many of these problems can be found in the engine of your lawn mower. Some very common situations are the lack of use for a long time or the lack of maintenance from time to time. This can lead to one or more problems that are easily fixable.
So we have researched the whole operation of a lawn mower and the main situations you might encounter. You can even save a lot of money by avoiding calling in an expert for a problem you can fix yourself. So let’s get down to work to check what’s wrong with your lawnmower.
Why does my lawnmower start and then die?
Some lawnmowers may start working and stop immediately. This usually happens with lawnmowers that have been in use for some time and there are at least 4 reasons for this.
- The carburetor bowl is clogged or the carburetor has a high level of accumulated dirt.
- You have not used your lawnmower for a long time and the fuel inside is too old.
- One or more of the spark plugs inside the lawnmower engine is fused or fouled.
- You have put too much engine oil in the tank of the lawnmower.
A lawnmower has an engine that requires a good level of maintenance, just like the engine of a machine or vehicle. Lack of maintenance could be the reason for most of these problems. There are also other situations in which a lawn mower can die, and these are mentioned below.
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Why Lawn Mower Dies? – Possible Reasons and Solutions
While some lawnmowers do not work at all, there may be others that work for a few minutes and then shut down. All of this has an explanation and in fact, several reasons why a lawn mower stops working from one moment to the next. That’s why here are the main causes you might encounter.
1. Lawn mower dies when PTO engaged
Many users decide to repair and replace parts without sufficient experience. This can result in a belt being routed incorrectly. If the blades are engaged, the engine may shut down anyway. So the important thing here is to check whether the belt of your lawnmower is routed correctly.
If you do not have the appropriate knowledge, you can always consult the owner’s manual or a professional to perform this task. You must reach into the belt guard and remove the belt guard. To do this you need to apply the lowest configuration of the platform. Once you find the belt lift this piece above the pulley.
This will allow you to remove the pins that are used to support the platform. The next step is to slide the mower deck off the mower so you can check the position of the belt. Each mower has its design and it may be necessary to check the owner’s manual to remove the deck properly.
Many times it is necessary to remove the spindle covers for those who need to implement the correct belt routing. If you have successfully routed your lawn mower belt correctly and it is still not working, you may want to check the following problems.
2. Lawn mower dies when blades engaged
When your lawn mower has blades engaged, there are a few reasons to consider when troubleshooting the problem. Some of the reasons we can consider in this case are faulty safety switches or a mower that is in reverse.
The safety switches on a lawn mower are specially designed to prevent dangerous situations. A non-functioning safety switch could be activated without being pressed. So the most appropriate solution, in this case, is to replace the safety switches. If your mower is in reverse, it is not strong enough for some uses.
So you need to check and use the most suitable speeds of a lawn mower according to the terrain. Another of the most frequent reasons is the fuel pipes which can present some problems. The main inconvenience here is the clogging which happens when a lawn mower is not used for a long time.
The same happens with the fuel inside a lawnmower that has not been used for many months. Some components of the fuel can vaporize. This means that the gasoline loses effectiveness as time passes and it remains inside a gas tank of a lawn mower, machine, or vehicle. Simply remove all gasoline and add new gasoline.
3. Lawn mower dies when cutting grass
Not all lawnmowers can offer the same strength in operation. Some terrain or some particular grass may be too hard for your mower to cope with. This is where many manufacturers incorporate a safety system. The engine stops to prevent the excessive workload from causing it to explode.
When the grass on the ground is wet or the lawn is too dense, this can also be a problem. The best thing to do in this case is to work a little at a time, bearing in mind that your mower can cope with a certain level of workload at a time. To prevent wet grass from clogging your mower, you should avoid grass build-up on the blades.
As we mentioned, fuel can also be another problem to be aware of. Your lawn mower may simply stop due to lack of fuel. After a long time of use, the fuel line may also be clogged by a build-up of sediment and dirt. Here the solution is to replace the fuel if it is too old and clean the fuel line.
Another problem can be found in the inadequately maintained air filter. The air filter allows air to enter the engine preventing the entry of debris and dirt in general. When this filter becomes clogged, it does not allow enough air to enter the engine for proper engine operation. The air filter must be replaced or cleaned if it is a reusable filter.
4. Lawn mower dies when choke off
Some lawn mowers die when they choke off. Mainly this could happen due to some kind of carburetor problem. So if you have some mechanical experience in fixing your lawn mower, you can check the functioning of the carburetor to avoid and solve some problems.
First of all, it is necessary to understand that the carburetor is an essential part of your lawn mower’s engine. It is the part responsible for mixing the fuel and air that produce the power of the machine. This mixture must have accurate levels of fuel and air to achieve the expected result. When this mixture is out of balance, the mower can die.
Depending on the mower model, there may be several fuel lines to the carburetor. This all depends on the type of throttle adjustment that each lawnmower has. One of the best solutions for cleaning the carburetor of your lawnmower is engine oil.
There is no single type of engine oil that you can use for your mower or a vehicle. Among the best options are synthetic oils. This type of oil usually has different additives that allow it to clean an engine by removing as much dirt and debris inside the carburetor as possible.
5. Lawn mower dies when hot
The engine of a lawn mower works in a similar way to the engine of a car. This means that when your lawn mower is too hot, it can die at any time. Air leakage is one of the problems that increase the temperature of your lawn mower. The solution is difficult and requires detection and welding of the leaking air parts.
As mentioned above, one or more fuel lines may become clogged. This not only leads to an imbalance in the air-fuel mixture in the carburetor. Another problem is of course the temperature rise. So here a cleaning of the fuel lines will be important, which should be part of the maintenance.
The above problem could mean that the carburetor is not getting the right amount of fuel. Something similar happens when the air filter is clogged and not enough air is getting through. Either of these problems causes an excessive temperature rise which is detrimental to the engine.
Worn pistons are another problem that allows the temperature to rise. So the most appropriate solution is to replace these parts with new units. Finally, old engine oil or insufficient oil can also be a problem, so you should check the quality and quantity of oil in your lawn mower.
6. Lawn mower dies when let off the clutch
Some errors in the use of a lawn mower can occur due to the inexperience of a novice user. The engine can stall for several reasons, one of which is leaving the throttle in the choke position. In turn, the mower may die when the clutch is released if the fuel tank is empty or low on fuel.
When the mower has a low engine oil level, it is also possible to notice this same problem. Insufficient engine oil causes various problems and prevents smooth starts. Part of these problems can be noticed in the crankshaft and the smooth movement of the other parts of the lawnmower.
Another reason to be aware of is that the mower may stall when the crankshaft is released if one or more spark plugs are damaged. Spark plugs can be damaged by excessive use over time and usually show signs of burning. If this is the case with your lawnmower you should replace each faulty spark plug.
Finally, you can consider the accumulation of debris, small branches, and tree leaves. All of these can build up around the blades of your lawnmower. So if the ground you are working on with your mower has a lot of debris, you should clean the area around the blades every so often.
7. Lawn mower dies when clutch released
There can be several reasons why a poorly maintained lawn mower is difficult to operate. This is a fairly common situation as not everyone routinely uses their lawnmower. One of the most common drawbacks lies in the air filter which we have mentioned in previous problems.
A clogged air filter is always a problem for the entire operation of your lawn mower. The same situation happens when a vehicle or machine has problems with the air filter. It is this part that is responsible for getting air into the carburetor to mix with the fuel, without debris and dirt also getting in.
So your lawn mower could die or shut down when you release the clutch if the air filter is clogged. A similar situation occurs with a clogged fuel filter or clogged fuel lines. The mower may shut down when releasing the clutch or in any other situation if either of these parts is clogged.
It should also be noted that a faulty spark plug is always a problem for any type of engine. Spark plugs are an essential part of the combustion of the air/fuel mixture. Also, these parts have a certain service life and can become melted, damaged, or fouled. The solution to all these problems is to replace the spark plugs, air filter, or fuel filter.
8. Lawn mower dies when put in gear
Some of the reasons for this problem are similar to the reasons for the above problems. When starting a lawn mower that has a clogged filter, the engine stops. Here the user should check if the air filter is clogged. Reusable filters can be washed, while non-reusable filters must be replaced.
A clogged air filter prevents the amount of air that the engine needs to enter the air/fuel mixture for combustion. This can cause the engine to stall when you start the mower. The same happens if the fuel filter is clogged, as the required amount of fuel does not enter the carburetor.
Some users also encounter this problem if the safety switches are damaged and defective. When such switches are damaged, the most appropriate solution is to replace these units. Otherwise, the mower may stop when starting the engine or in any other circumstances.
Another problem is that the mower gets too hot in the engine for some reason. This could be too little engine oil, and therefore too much dirt accumulated inside the engine. Many engines are shut down at too high a temperature to prevent the engine itself from exploding. If this is the case, you need to check the amount of engine oil.
9. Lawn mower dies under load
Not all mowers are equipped to cope with the same workload. So a mower can stall or die when the grass is too thick or too high. One of the reasons this can happen is that the engine stops at a high temperature. This happens to prevent the engine from exploding under the excessive workload.
The best solution is to use a lawn mower on all terrains that do not present an excessive workload for the engine’s capabilities. The same problem can also be encountered when the air filter is clogged. This means that not enough air enters the carburetor to obtain a balanced mixture of air and fuel.
So once again the solution here is to replace the air filter if it is too clogged and deteriorated. You also can properly wash the air filter if it is a reusable part. In any case, air filters have a certain service life which is important to respect.
If the grass is too thick and bulky, this can be enough to clog the air filter itself. So here it is not sufficient to have a completely clean air filter. In such situations, it is necessary to deal with thick and tall grass in another way before using the lawn mower.
10. Lawn mower dies after 10 minutes
If you have a lawn mower that shuts off after 10 minutes of use, the problem may be in the fuel cap. The fuel cap has a special design to keep the fuel in good condition. It is also an important part that allows the fuel to reach the carburetor and mix with the air.
The fuel cap includes in its design a valve or breather. This allows some air to enter the fuel tank while keeping the petrol vapor inside. In this way, a vacuum can be prevented in the fuel tank. So this is what could be happening with your lawn mower.
When this fuel cap does not function as a breather, it means that no air enters the fuel tank. This is what creates a vacuum that increases as the minutes of lawn mower use pass. So, after about 10 minutes of use of your lawnmower, the fuel will no longer be able to reach the carburetor.
If this is the case, it means that the fuel cap of your lawnmower is damaged for some reason. Here the most appropriate solution is to replace the fuel cap to allow some air to enter the fuel tank.
11. Lawn mower dies at full throttle
Finally, we can consider it a problem if your mower shuts down when running at full speed. It is likely that in this type of situation your mower can idle but not run at full speed. The problem in this type of situation is usually a clogged carburetor.
When the main jet of your engine’s carburetors clogs, it means that not enough fuel is entering the engine. In turn, the engine needs more fuel to run at full speed compared to idling. So the clogging allows a lawn mower to run only at idle speed.
If you have the possibility you can clean the main jet and the whole carburetor to solve this drawback. When the problem is too severe, then you need to replace the carburetor or the main jet. The latter task will probably require expert workmanship to avoid beginner’s mistakes.
To clean the carburetor completely, there are different solutions and cleaners that you can use. Many users prefer to clean the entire carburetor instead of just cleaning the main jet. This solves the problem of the lawn mower and avoids future problems.
12. Lawn mower dies after removing jumper cables
Some users need jumper cables to start the mower. However, this lawn mower may stop working if the battery has some problems. The lawn mower battery has a certain life span just like any vehicle battery.
The battery of your lawnmower is probably too deteriorated or depleted. So a suitable solution is to fully charge the battery before using your lawnmower again. For that, you need to use a power source with the same voltage as the battery of your lawn mower.
This is important as a different voltage can damage your mower’s battery. Once the battery is fully charged you should check the operation of your lawn mower. Here it is important to consider that the starter may be faulty despite a fully charged battery.
So it is important to check the condition of the spark plugs, which are part of the vehicle’s ignition system. When a spark plug shows signs of burning, it means that the spark plug is fused and no longer works. The solution is simple and involves replacing every spark plug that is found to be defective.
Why Does a Lawn Mower Stop After a Few Minutes?
Based on the above-discussed drawbacks, there are a few main problems why a lawn mower may stop working after a few minutes. The ignition coil or spark plugs are fundamental parts of a lawnmower’s operation.
So if these parts are defective, the engine stops after a few minutes. A clogged air filter or a clogged fuel line is also more than enough reasons why your lawn mower may stop. You should check these issues along with the fuel cap and carburetor to make sure these parts are in good condition.
How Do You Fix a Lawn Mower that Starts then Dies?
The most important thing is to implement full maintenance to get a lawn mower that has died back into use. Use a carburetor cleaner to clean the carburetor and high-quality synthetic engine oil. You should check the condition of the spark plugs and ignition coil. You also need to check the condition of the fuel cap and the life of the battery.
To avoid many of the most common problems that cause a lawn mower to die, maintenance is one of the most important factors. You also need to use your mower regularly. Many problems arise when a lawn mower is not used for many months, just like a vehicle.