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What might be the cause? Is there something wrong with the lawn mower, despite you maintaining it as required? Should you call a certified John Deere lawn mower repairs?
Before intending to call a John Deere lawn mower repair shop or take it back to the dealers, there are a few reasons why your lawn mower won’t, among which include the battery, the ignition switch, the spark plug, the carburetor, or no adequate amount of fuel in the tank.
While these few listed might be the reasons your John Deere lawn mower won’t start, there are other complex reasons, and we won’t advise you to work on it yourself if you lack the expertise to fix the mower.
Hence, in this article, we’ll tend to focus on the aspects you can work on yourself without seeking assistance from a professional.
Note that if, following the steps in this article, your lawn mower doesn’t start, seek professional assistance. But if it’s still new and on warranty, you should return it to the dealers.
More articles that might help you with your John Deere Lawn Mower starting issues.
How to Fix a John Deere Lawn Mower That Won’t Start
If you want to get your lawn mower started, you have to follow the steps outlined below. Note: These are basic things you can try yourself if you aren’t a professional.
Here are the steps to follow:
Step 1: Check the fuel tank and the state of the fuel.
Without the right amount of fuel or a good fuel, your John Deere Lawn Mower won’t start, no matter how hard you try.
Sometimes you might think there’s enough fuel or gasoline in the fuel tank; however, actually, there’s something that could cause the engine to start.
Apart from your mower not having the adequate fuel needed, if the fuel has been long on the fuel tank, it might also cause the mower not to start.
What you should do in this case is check if the fuel is enough to start the engine. If the fuel isn’t enough, it’s required that you add more to the tank.
Additionally, if you check the tank and notice the state of the fuel in the tank is bad, smelling, or stalling, it’s recommended that you drain the fuel from the tank and add fresh gasoline or fuel.
It’s recommended that you use 87 octane and not more than 10% ethanol for your lawn mower. When draining the fuel, make sure you clean inside the tank to prevent dirt from contaminating the fresh fuel or gasoline you want to put in.
In addition to adding fresh fuel to the tank, there are times you will want to leave your mover for days. Eventually, if it’s more than 30 days, we recommend you add a fuel stabilizer to the fuel or gasoline or drain the fuel from the tank.
Step 2: Check the fuel shut-off valve and the fuel line.
The fuel shut-off valve is responsible for stopping and allowing the flow of fuel through the fuel line to the carburetor.
If these two components of your mower are faulty, there won’t be a free flow of fuel, which in turn causes the mower not to start.
The best you can do in this situation is to change the fuel line, especially if it’s leaking fuel, broken, or faulty.
As for the fuel shut-off valve, you can remove it from the tank because that’s where you can normally find it—clean it—and fix it back.
However, in situations where the valve can’t be cleaned, you should change it to a new one, depending on the exact type of John Deere lawn mower you are using.
Step 3: Check the Fuel Filter
If you have checked the fuel tank and state of fuel, the fuel valve, and the fuel line, all are okay. You should also check the fuel filter.
The fuel filter location differs according to the different lawn mowers John Deere manufactured. You can check your manual for the actual location.
The fuel filter is responsible for filtering dirt and other substances from getting into the carburetor. If there is too much dirt, it will eventually clog the fuel filter and prevent the right flow of fuel.
In most cases, the fuel filter is usually inside or outside the fuel tank. What you should do in this aspect is locate the fuel filter, clean it, or replace it if needed.
Step 4: Check the carburetor and choke.
The carburetor is the heart of your lawn mower; if it’s faulty, your mower won’t start. If it starts, it will be sputtering till it shuts down.
The location of the John Deere lawn mower carburetor differs depending on the model you’re using. The same goes for the choke. You can check the manual of your lawn mower for the actual location.
Before you start losing your carburetor for servicing, first check the choke to see if it’s in the right position. We can’t talk much about this aspect because each choke position of the John Deere lawn mower is different. Just make sure it’s in the right position, following its manual.
Then, you move on to servicing the carburetor if it still doesn’t start. Start by losing the carburetor, then remove all the jets from the carburetor. Use a carburetor cleaner and clean the jets, making sure everything is fine, and tie them back to the mower.
Step 5: Check the air filter.
Next, you check the air filter, whose responsibility it is to filter dirt, airborne molecules, and other things that might disrupt the engine by preventing air from entering the mower.
Once the air filter is clogged due to this dirt and molecules, there won’t be enough air going through the mower, which will in turn cause it not to start. Even if it does, it will sputter and shut down after a few minutes. At least 20 is enough.
What you should do in this case is clean the air filter or replace it if needed. Generally, we recommend you change the air filter every year.
Step 6: Check the spark plug and ignition switch.
The spark plug and ignition switch are also two of the main factors that might contribute to your mower not starting if they are faulty.
The spark plug is used to ignite the air-fuel mixture in internal combustion engines by producing a spark. But there is no way the spark plug can work if the ignition switch is faulty or the ignition system as a whole is faulty.
If the ignition system, such as the starter solenoid, ignition coil, etc., is damaged, you should seek professional help, as it’s a complex issue—not that complex, though.
So what you should do in this case is diagnose the spark plug, ignition switch, and spark plug wire and see if you find any fault. If there’s any, fix it by replacing it.
Step 7: Check the battery if you’re using one.
Next, if you’re using a battery-type lawn mower, you should check the battery to see if it’s charged, low, or dead.
If the battery is charged and your mower isn’t starting, there might be other reasons, but I will suggest you use the manual recoil starter if it has one to check if the mower will truly start.
But if the battery is dead, we suggest you charge it fully or replace it with a new one if it seems to be giving you more issues.
Step 8: Low oil pressure or oil sensor
Lastly, check if there’s enough engine oil in your lawn mower by using the engine oil gauge by the side of the mower’s crankcase.
If there’s no engine oil or the engine oil has been long overdue, you should change the engine oil or add to it.
But there are cases where you will have oil in your mower, yet you will be seeing an oil pressure sensor showing you no oil, making your mower start. If you’re in this situation, we discussed how you can fix it in our previous articles:
Is Your John Deere Lawn Mower Won’t Still Start?
If you’ve followed all the tips in this article, yet your mower still has not started, other reasons not outlined in this article might be the cause that only professionals can help you with.
Some of those issues involve your mower having valve clearance, one of the two valves being damaged, the ignition coil, and other related issues.
Do you have some questions for us to answer? Please comment below or contact us.