House chores, such as cutting the overgrown grass, can be fun or frustrating, depending on the condition of your machine. It can be hassle-free and fun when your lawnmower works well, starting when switched on. But frustrating when the machine refuses to turn on and do its work.
There can be several reasons why your lawnmower won’t start, and not all of them require the presence of a professional. It might require jumping the solenoid on the lawnmower.
Read this to get the inside scoop on how to jump solenoid on a lawnmower.
Simple DIY troubleshooting can solve the problem in minutes and get the machine working as it should. Most lawnmowers are powered by electricity or gas and have multiple starters in them. The function of these starters, as the term implies, is to get the grass-cutter machine to “start. It does this by transferring the power current from the batteries to the ignition.
The two key starters in the lawnmower are the starter motor and the starter solenoid. The starter solenoid is located inside the motor and it is responsible for sending electric currents to the motor, which then powers the engine. So it is an essential part of the automatic starter system of the mower.
One of the reasons a lawnmower might fail to start is if the solenoid is not working properly. This is the first thing to check if your machine does not start, and we’ll explain how to do that.
But before that, let’s show you how to jump the solenoid on your mower first.
How to jump solenoid on a lawnmower
Follow these steps to jump your solenoid and get it to start your mower:
- Turn on the ignition switch – Ensure the ignition button is in the ON position. It is necessary to turn on the switch so that the coil can receive power.
- Find the solenoid on your mower – It should be located near the battery at the back of the mower engine. There’s a fat red wire that is connected to the smallish device on the mower frame or behind the engine compartment. That’s the solenoid. You will see two points at the back of this device. These are the points you have to jump.
- Check the connection on the mower – Make sure the connections are intact. The solenoid connects to the starter motor through a stiff piece of thin copper. Another thick dark wire connects the solenoid to the positive terminal of the mower battery.
- Jump the solenoid – Use a jumper cable. Attach one point of the jumper cable to the stiff piece of copper. And the other point to the part where the battery connects to the solenoid. That’s all.
If the mower does not start at this point, then the solenoid might be broken or damaged. Or there might be another problem.
But to really identify if the problem is the solenoid, we explain how to check for a few signs of a bad solenoid on a mower.
How to check if your solenoid starter is broken
One of the first things you should do if your mower won’t start is to check the starter solenoid. We will explain how to do that step by step.
But ready these three things before you begin:
- A jump cable
- Spanners and wrenches (to use to move components around)
- A digital voltmetre (or any device to weigh voltage)
You need to also have someone ready to help you turn on the ignition to test.
Now, test the solenoid starter by following these steps:
- Find the starter solenoid – We have explained how to identify your starter solenoid. Remember that the stiff piece of copper connects the starter to the motor. While the other cable connects it to the positive terminal of the battery.
- Do a click test and check the battery if necessary – Have your person turn on the ignition and listen for a click sound. You should hear the click once the motor and solenoid engages. If there’s no sound, the starter solenoid might be bad. Another possibility here might be a problem with the battery.
Use your digital voltmetre to check the battery voltage through the following ways:
- Attach the red wire to the positive terminal of the battery, and the black wire to the negative.
- The volt should not be lower than 12. If it is lower, or there’s no reading, it indicates a low battery, or it might be dead.
- But if you confirm that the battery is alright (that is, around 12 volts), then you should move to the next step of your starter solenoid check.
- Check the current on the solenoid – If the starter solenoid makes a click sound that is too weak, it might be bad, or the problem may be from the control circuit.
To identify the problem, check for current resistance in the control circuit doing these steps:
- Connect your jumper cable to the control circuit terminal and the input solenoid terminal.
- Then listen for a stronger click sound from the starter solenoid and motor. If you don’t hear a sound even though the connections are alright, your solenoid might be faulty.
- Measure the voltage on the solenoid – If the click sound is weak when you turn on the ignition, the solenoid might not be receiving enough power from the battery. If so, you should check the voltage on the solenoid starter. Use your digital meter to check this.
First, set the DC voltage scale on 15. Connect the red wire of the digital multimeter to the positive terminal of the battery.
Then the black wire to the negative terminal. The battery should have around 12 volts if nothing is taking power from it.
Get your person to turn on the ignition. Once this is done, the voltage should drop to around 0.5 volts if the battery is in superb working condition.
After this, measure the drop in voltage on the solenoid by attaching the multimeter’s red wire to the output solenoid terminal.
Then connect the multimeter black wire to the input solenoid terminal. Then, get the person to turn on the ignition switch.
The voltage drop should be the same as the battery voltage earlier. That’s 0.5 volts. If the drop is less than then the problem is the solenoid.
If not, the problem might be an electrical fault.
In addition to these tests above, there are common signs that can indicate a bad starter solenoid on the mower. We outline these symptoms below:
How to tell that your lawnmower starter solenoid is bad
- The mower refuses to start when you turn it on – Yes, this sounds obvious. But it could be a symptom of other problems on the machine. The first thing you should check on if the mower does not start is your starter solenoid. You can start by jumping the solenoid. We’ve explained the simple process of doing this. Then you carry out other tests.
- No click sound when you turn on the ignition – When you turn on the ignition switch, you should hear a click sound. If there’s no such sound then the starter solenoid might be broken.
- Weak click sound when you turn on the ignition – When the click sound is weak, it might indicate that the solenoid is not able to engage the starter motor to power the mower.
- Repeated clicking sounds – Though this is mostly indicative of a dead battery, if the solenoid is faulty and can not send adequate current to the starter, it can give this sign. The repeated clicking can result in low battery voltage, causing the mower to refuse to start.
- On-again-off-again mower – If the mower starts today and does not start the next time you try to use it, and it does this often, you might need to check on the solenoid starter.
Jumping your solenoid is a straightforward process. By following the above steps, you can do it easily. If that does not start your mower, then there might be another problem with the machine. This might be related to the solenoid or not.
We have explained how you can check if the fault is the starter solenoid. If you follow all these steps and still can not figure out the problem, you should then reach out to a professional for help.