Starters

What is an automotive starter and where is it located?

A starter is an electric motor that helps start the process of internal combustion inside your vehicle's engine.  It is generally located underneath the engine near where the transmission engages with the engine. In some cases, the starter may be found on top of the engine near the intake manifold. The starter motor is the main component to your vehicle's starting system and is responsible for the initial turning of your engine until the ignition and fuel systems take over. Once the engine has started running, combustion in one cylinder drives compression in an adjacent cylinder so, as long as fuel continues to be applied, the system is self-propelling. In order to start this process, though, something must start turning the engine. 

Before the invention of the electric motor, hand-cranks were used to start automotive engines. Hand-cranking an engine was neither easy nor entirely safe. Occasionally, the engine would kick back and the crank could injure the operator, resulting often in a broken thumb or a broken wrist. Thankfully, engineers at Cadillac came up with the idea of inventing an electric motor that could start the engine. This made motoring safer and more accessible for more people. 

Although there are different types of electric starters, the basic principle of operation remains the same. The process of starting your vehicle begins when the ignition key is inserted into the ignition key cylinder and turned beyond the on position, unless of course you have a car or truck that has a remote starter. Remote starters just bypass the key, making the vehicle act like the key is in the ignition even though it is not. Either way, this action activates the ignition switch and, in turn, electric current from the battery is then feed to the starter solenoid which in turn spins the armature which drives or “pushes” a pinion. That pinion engages with the engine flywheel ring gear and drives the crankshaft. The crankshaft of course translates the up and down motion of the pistons into the rotating motion that is needed to power the automobile. Once started and the key is released, the key will then return to the “on” position as a result of the “start” position being spring loaded. The ignition switch stops feeding current to the solenoid and thus the power supply to the starter motor is cut, shutting it “off” essentially.

The starter must also have some way to keep the engine from turning the pinion. The ratio of the ring gear teeth to the pinion teeth is very high, so once the engine is turning at speed, if the two gears were still engaged, it would turn the starter much faster than it could handle, causing damage to the motor.

There are two methods of keeping this from occurring: the inertia system and the pre-engaged system. In the older inertia style starter, the pinion is threaded on to the motor shaft like a nut on a bolt. As the shaft spins, the pinion threads out. There is a stop that holds it once it reaches the end and engages with the ring gear. Once the engine starts turning, the much faster movement of the ring gear essentially spins the pinion back and threads it back down the shaft. These types of starters require the pinion to start spinning before it engages with the ring gear. When the spinning pinion engages with the stationary ring gear, some wear of the gears can occur. 

To reduce this wear, pre-engaged starters were invented. In these, current from the battery activates a solenoid that pushes the pinion out, then another current starts the motor. The pinion on these has a one-way clutch like the freewheel mechanism on a bicycle. Automobile starters today use the pre-engaged system, as inertia style starters haven’t been used on automobiles for many decades.

Some more recent starters use a process called gear reduction. This is the most common type of automotive starter used after the mid-1990s. Before that, direct drive starters were the most common automotive starter from around 1950 through the mid-1990s. While similar in operation, with gear reduction starters, the pinion is not directly attached to the armature rather they have transmission gears from the starter motor itself to the output gear that meshes with the flywheel. These extra gears provide more torque, thus allowing the starter motor to be able to turn over the engine faster and with less effort and drain on the battery. Gear reduction starters are also half the size of direct drive starters and weigh much less.

For an even more in-depth explanation of starters, including their history, more details on how they work and the different types, and more, check out our starter motor guide.

How do I know if my starter needs to be replaced?

Starters can fail from the malfunctioning of or damage to the internal parts. The electrical parts inside starters are not very resistant to heat, which means the starter can't run for long. Cranking the engine too long or not letting the starter rest long enough can overheat the internal parts, but they can also wear out from repeated use, like on delivery vehicles that start and stop often. Ignition timing problems could also cause engine kickback, which can damage the starter. 

If the dash lights turn on with the key in the ON position but the vehicle won't start, it's not the battery and may be the starter. Some other signs include slow or no engine cranking, slip or chattering noises, or hearing the starter motor spinning with no engine cranking.

Can I replace a starter motor myself?

It will take some effort, but it is certainly possible to replace your car or truck’s starter yourself if it has been determined that you in fact need a replacement. The most difficult part of replacing the starter may be accessing it. Common steps include waiting for a cool engine, raising and securing the vehicle to access the starter, disconnecting the battery,  disconnecting the wiring to the starter, and unbolting it. Starters can vary depending on the vehicle, so make sure you have the correct starter designed for yours.

Need a starter replacement for your vehicle?

If you are having issues with your engine starter, it’s important that you address them quickly. You don’t want to risk damaging your engine or not being able to drive your car or truck. Then you’ll be in a lot of trouble. Remember, the starter motor is your vehicle's heart; it brings your engine to life and it sets your vehicle into motion. Like any smart member of the human race, you have to take care of your heart! If you are in need of a starter replacement for car, truck van or SUV then you have come to the right place. 1A Auto offers a large selection of aftermarket starters for many makes and models, and at great prices.

At 1A Auto, we offer brand new starters, not rebuilt or remanufactured. This means no core charge or dealing with the hassle of returning a core. Our aftermarket starters have all new components, and heavy duty bearings for long life. Our new starters also come with the correct starter solenoids for a direct original equipment replacement.

We also make shopping for a replacement starter for your car, truck, SUV or van easy at 1A Auto- we're here to help you select the right part for your vehicle! Call our customer service toll free at 888-844-3393 if you have any questions about our aftermarket starters, warranty, compatibility or to purchase, or you can buy online.