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Can a Bad Starter Drain a Battery?

Can a Bad Starter Drain a Battery?

Sometimes, a car repeatedly won’t start. Can a bad starter drain a  battery? What problems do starter motors have?

A bad starter motor can drain a battery. If your car won’t start in the morning, it could be because your starter motor is broken. There could also be problems with the relay, solenoid, gears, and many other things. 

If your starting motor is damaged, it might keep running after the engine starts, which can create expensive damage. 

Can a Bad Starter Drain a Battery?

Every time you try to start a car, it drains the battery a little. If you repeatedly try to start it but fail, the battery will die. You will then need to jumpstart your car to get it going. 

If your starter has any problems, you should get your car looked at. Otherwise, your car might fail to start when you really need it. 

A bad starter can leave you with a dead battery and make you unable to get somewhere important on time. 

How Does a Starter Motor Work?

A starter motor turns your main engine over to get air into the engine. If the starter motor isn’t working properly, not enough air will get into your engine and it won’t ignite. When your engine turns over, that creates suction, which pulls air into your engine. 

The starter motor is electric and not a gas engine. Therefore, it needs power from your battery to work. First, the battery powers the starter motor, then the main engine starts, and then the main engine recharges the battery. 

None of this will work if the battery is dead. You will need an external power source to charge your battery enough that your starter motor will work, your engine will start, and your engine will charge your battery fully. 

What Problems Do Starter Motors Have?

If there is obviously something wrong with your starter motor, don’t delay taking it to a mechanic. Continuing to use a faulty starter motor can damage your car.

One of the worst problems is if the flow of power doesn’t stop after you stop turning the key. This can damage the transmission flywheel or the whole starter system, leading to expensive repairs. 

Oil On Your Starter Motor

If there is an oil leak, your starter motor may get oil all over it. This can prevent your starter motor from working and your car from starting. 

Problems With Relay

The relay that feeds electricity from your battery to the starter motor might not be working properly. 

Bad Flywheel Or Gears

Bad Flywheel Or Gears

Sometimes, there isn’t anything wrong with your starter motor, but there is something wrong with the flywheel or gears. Your starter motor will start, but this won’t turn your engine over. You will hear your starter motor working, but the engine won’t start. 

Problems With Solenoids

When you turn your key, a solenoid brings the signal from the key down to the starter motor. It is a small metal piece that can become damaged. 

A bad solenoid can make your car fail to start. A much worse potential problem is that your starter motor will keep going after the engine starts. This can damage the flywheel, which is expensive to fix. 

What If the Starter Motor is Bad But the Battery is Okay?

Sometimes, you might see the dashboard turn on but not hear the starter motor do anything. In that case, the starter motor or the solenoid is damaged, but the battery is fine. The dashboard wouldn’t light up if the battery wasn’t producing power. 

How Do Bad Starter Motors Drain Batteries?

Every time you try to start your car, that drains power. If the starter motor has problems, you will have to make multiple attempts to start your car. There are only so many attempts you can make before the battery runs out. 

Don’t Leave the Lights On

Leaving the lights on is one of the simplest and most avoidable ways to drain your battery. If your lights don’t turn off automatically, stay in the habit of turning them off each time.

If you are stressed out and your mind is on other things, it is easy to forget little things. If you keep forgetting to turn off your lights, put a small note in your car to remind you. 

Other Things Use Battery Power

Lights inside of your vehicle also use up battery power. Your radio, music player, door lights, cigarette lighter, and many other things work on the car battery. It’s worse if you use more than one thing at once. 

The Temperature

Many people are familiar with the car not starting on a cold winter morning. Very hot temperatures can sometimes also affect the battery. 

Is the Alternator Working?

Normally, your car battery should charge to full when you drive for a short while. However, if your alternator doesn’t work, it won’t charge much or at all, and your car might fail to start the next time you try. 

Making Very Short Trips Often Isn’t Good

Don't take your car every time you go to the corner store, especially in bad weather. 

A short trip won’t generate enough battery power to replace what was lost, so your car may fail to start after a few short trips. 

Replace Your Battery

Car batteries and not just cell phone batteries get weaker as they get older. A car battery is based on chemicals, and the chemicals change form over time, weakening the battery. Your problems might end as soon as you replace it.

Key Takeaways to a Bad Starter Draining the Battery

A bad starter motor can lead to a dead battery. If you struggle to start the engine due to a bad starter motor, each attempt drains power. 

A starter motor might fail because it has oil on it from an oil leak, bad solenoids, or a bad relay. The gears that transfer power from the starter motor to your engine might be damaged. 

If you only drive for a short time, it won’t generate much power, less than it took to start your car. 

Zach Reed

Hi, I'm the founder of! Having owned a wide variety of vehicles in my life, I was astounded at how hard it can be to find answers to common automotive questions. Rather than sit idly, I decided to create this website to help others!