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John Deere Tractor Won’t Start Just Clicks—What Could Be Wrong?

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There's nothing worse than mentally preparing yourself to mow or do yard work with your John Deere tractor only to realize it won't start. So, if you're wondering why it won't start and will only click, you've come to the right place. We've researched the topic in-depth and have some reasons this might be occurring.

If your John Deere tractor won't start and only clicks, it could be because of a:

  • Bad starter solenoid
  • Faulty battery connections
  • Dead or damaged battery
  • Failing or seized engine
  • Bad spark plugs

We've given you a few issues that might be preventing your tractor from starting, but keep reading as we elaborate on each one. We'll discuss the symptoms of each problem and how to diagnose it. Additionally, we'll answer some other questions you might have about your John Deere lawnmower. 

A line up of green John Deere tractors, John Deere Tractor Won't Start Just Clicks—What Could Be Wrong?

What Could Be Wrong with Your John Deere Tractor

Unfortunately, just like any other vehicle with a battery and an engine, lawnmowers can also experience problems that can prevent them from starting. Sometimes these problems are accompanied by a clicking noise when you turn the key. If there's a clicking noise, it can be narrowed down to some of the problems we listed earlier. Let's discuss them!

A huge green John Deere tractor photographed at the farm

Bad Starter Solenoid

The most common cause of a lawnmower not starting but clicking is a bad starter solenoid. A solenoid along with a battery helps the starter motor turn the engine and run the vehicle. If any one of those components is faulty, your lawnmower may not start. Fortunately, there are ways to diagnose whether the issue is because of the solenoid. 

How do you test a John Deere starter solenoid?

To test a John Deere starter solenoid, you will need to bypass the solenoid and see if the tractor will start. If the tractor starts after you've bypassed the solenoid, the solenoid is the problem. If the tractor doesn't start, the problem is likely with a different part. 

How do you start a lawnmower with a bad solenoid?

For safety reasons, we don't recommend that you bypass a solenoid to start your mower. However, it is possible.

To start a lawnmower with a bad solenoid, you will need the person who is going to drive the lawnmower to sit on the seat. This is because the mower has a killswitch in the seat, and the mower will cut off if the seat is unoccupied. Once someone is in the seat, you will need a screwdriver or pliers.

You will use the screwdriver to make contact between the starter post and battery post, which will create a connection and get the engine started. 

To see exactly how this is done, check out this helpful YouTube tutorial:

How much is a John Deere solenoid?

Fortunately, if you do need to replace the solenoid, it is relatively inexpensive to do so. You can purchase solenoids online and at some auto parts stores. A John Deere solenoid will cost you between $15 and $25 to replace. 

How do I know if my John Deere starter is bad? 

Trying to diagnose whether the starter is bad is a little more tricky. To find out if the starter is bad, you will first have to determine that no other part could be causing the tractor to not start. Once you've tested the battery, the fuse, any connections, and the starter solenoid, you can then assume the issue lies with the starter. 

Faulty Battery Connections

A dead battery could be the problem with your lawnmower, but before we get onto that,  let's talk about the connections. The problem could be as simple as some loose connections.

After all, a lot of vibrations are generated when you mow the lawn. It's not impossible for something to get knocked loose. Carefully inspect the connections heading to the battery and see if anything needs tightening. 

The connections could also be dirty or corroded. If the connections seem dirty, take a moment to clean them. If they are clean and tight, the connections may not be the issue, and it's time to check the battery itself. 

Dead or Damaged Battery

One of the more simple problems to diagnose is a dead battery. Be sure to check the battery for any visible corrosion. If you can't tell whether the battery is bad from looking, you can test the lawnmower's battery using a multimeter.

A multimeter will tell you the battery's voltage output. If it reads over 12.7 volts, the battery is fine. However, if it reads less than this you will likely need to replace it with a new one.

If the battery isn't completely dead but seems to need jumping a lot, the battery could be damaged. If the battery's case is cracked or broken, it can make the battery work harder. This can cause the battery to die more quickly. 

 

Click here to see Multimeter on Amazon.

How long does a john deere battery last?

If you're having battery trouble, it might just be time for the battery to be replaced. A John Deere battery will last about 3 to 4 years, so if it's been about that long since you got the tractor, this might explain some of the issues you're having.

Once you've replaced your battery, there are some steps you can take to prolong your new battery's life. You may be able to prolong your lawn mower's battery by running the mower every so often during winter. Allowing it to sit without use for a long period of time may shorten its lifespan.

You should also protect the battery from any extreme weather conditions. If you can, keep it covered in a garage or shed when it's not in use. 

Failing or Seized Engine

Hopefully, this isn't the cause of your lawnmower problem, but if you've ruled out every other possibility, your lawnmower's engine might be failing. A failing engine can be because of improper lawnmower maintenance. If you haven't changed the oil or it's running low, you could be causing damage to your engine.

The engine might also be seized or "locked up." If this is the case, you can use penetrating oil to help get the engine moving again. You should also give the lawnmower an oil change during this time.

Click here to see Penetrating Oil on Amazon.

Bad Spark Plugs

Spark plugs being faulty or bad can also cause a number of problems for your lawnmower, especially the mower's engine. One of the symptoms of a bad spark plug is the engine being difficult to start or not start at all. You can tell if your spark plug is bad by taking a look at it. If there are any deposits, cracks, or it just doesn't look quite right, you should replace your spark plugs.

What kind of spark plug does a John Deere lawnmower take?

Spark plugs are really cheap and easy to replace, so if you need to replace yours, don't worry too much. Replacing spark plugs should be part of your routine maintenance anyway. Some John Deere lawnmowers can take a Champion RC12YC spark plug. However, you should consult the owner's manual of your lawnmower for the best recommendations. 

Click here to see Spark Plug on Amazon.

How often should lawn mower spark plugs be changed?

To keep your lawn mower running well, it's important to perform some routine maintenance to give it the best chance of lasting as long as it can. Just like you should perform regular oil changes, you should also change the spark plugs occasionally. To ensure proper maintenance, you should change your lawn mower's spark plugs once a year or once a mowing season. 

Other Reasons Your Mower Won't Start

If it doesn't seem like any of the previous problems are the issue, there are some other reasons your mower might not be starting. However, the following issues may not be accompanied by a click. Other reasons your mower won't start might include low gas or oil levels or an issue with the ignition switch.

It could also be because the gas is stale, or the alternator is bad. As you can see, there are a lot of parts to a mower, and a number of them could be to blame. If it feels overwhelming, don't be afraid to call a technician for help. 

Final Thoughts

A line up of green John Deere tractors

We hope our article has provided some insight into what might be wrong with your mower. Fortunately, the problems your lawnmower might be facing when it clicks but won't start can often be diagnosed and fixed by yourself. However, if any of this seems over your head or the problem still persists, there are professionals you can call for guidance. Good luck!

For more reading, check out some of our other blog posts below:

Can You Use Car Motor Oil In A Lawn Mower?

20 Types Of Tires You Should Know