Every memorable drive you've experienced in your life begins with the successful operation of the starter on your vehicle. The starter on today's cars, trucks and SUVs is attached in the rear of the motor, where a gear on the starter aligns with the vehicle's flywheel to begin the ignition process. Once the engine turns over, fuel is introduced to the combustion chamber and is ignited thanks to the ignition system being activated. When this process works correctly, your engine comes to life. However, when the starter begins to wear out or break, it will impact your ability to drive the car.
Over a period of time, the starter motor will eventually runs its course and wear out. The two components inside the starter that commonly fail are the solenoid (which sends an electrical signal to the starter motor to activate) or the starter motor itself. When this occurs, the starter will be rendered useless and needs to be replaced by a certified mechanic. Although many of the internal components inside the starter can be fixed, it's recommended by most automotive manufacturers to replace the starter, so as to avoid future breakdowns.
Like any other mechanical device, when the starter fails or is beginning to wear out, it will display a few warning signs. Noted below are a few of the indicators that will let you know that a problem with the starter motor is likely.
1. Engine won't turn over
The most common indicator that a problem with your starter exists is when you turn your key and nothing happens. This is often caused by the starter solenoid or motor that has burnt out, or is experiencing an electrical issue. However, this problem may be caused by a dead battery as well. If this occurs, you'll have to contact a mechanic to inspect the starter, ignition system and other electrical components, as it may be a sign of multiple issues.
2. Starter engages but doesn't spin the motor
There are times when you'll turn the ignition switch and hear the starter activate but will not hear the motor crank over. Issues with the starter are sometimes mechanical in nature. In this case, the problem may be due to the gears that are connected to the flywheel. Either the gear has stripped or has become dislodged against the flywheel. In either case, the engine won't turn over and will require that you have the starter replaced...
How Does a Starter Motor Work?
When you turn the key in your car’s ignition, the engine turns over and then cranks. However, getting it to crank is actually much more involved than you might think. It requires a flow of air into the engine, which can only be achieved by creating suction (the engine does this when it turns over). If your engine isn’t turning, there’s no air. No air means that fuel can’t combust. The starter motor is responsible for turning the engine over during ignition and allowing everything else to happen.
How your starter works
Your starter is really an electric motor. It engages when you turn the ignition to “run” and turns the engine over allowing it to suck in air. On the engine, a flexplate or flywheel, with a ring gear around the edge, is attached to the end of the crankshaft. On the starter, there’s a gear designed to fit into the grooves of the ring gear (the starter gear is called a pinion gear).
When you turn the ignition switch, the starter motor is energized, and the electromagnet inside the body engages. This pushes out a rod to which the pinion gear is attached. The gear meets the flywheel, and the starter turns. This spins the engine over, sucking in air (as well as fuel). At the same time, electricity is sent through the spark plug wires to the plugs, igniting the fuel in the combustion chamber.
As the engine turns over, the starter disengages, and the electromagnet stops. The rod retracts into the starter once more, taking the pinion gear out of contact with the flywheel and preventing damage. If the pinion gear remained in contact with the flywheel, it’s possible that the engine would spin the starter too fast, causing damage to it.
How to Change a Starter Motor
Knowing how to change a starter motor will help you stretch your car maintenance budget, so you can use that money for other maintenance tasks. Using the correct steps you'll avoid ending up with an electrical short circuit, damage to the new starter motor or some other components; and, most importantly, you'll pay attention to key procedures that may apply to your particular vehicle model. But don't worry, you don't need to have much experience working on cars. And, on most vehicle models, you can replace a failed starter at home using some common tools you might already have in your toolbox.
So let's start.
Tools You'll Need:
Wrench set
Floor jack, 2 jack sands, 2 wooden blocks
Goggles
Ratchet, extensions and socket set
Wire brush
Shop rags
Degreaser, if necessary
Torque wrench
Removing the starter motor
In most cases, replacing a starter motor requires a few common tools you might already have in your toolbox. However, before you start, locate the starter in your particular vehicle model.
Some starter motors sit towards the lower or upper section and to one side of the engine, next to the transmission — on the radiator side. If you can't reach the motor from above, you'll need to lift the front of the car, secure it safely on jack stands, choke the wheels and work on it from under the vehicle.
Other models may locate the starter between the firewall and the engine, in the lower section. It makes for a little more difficult but not impossible repair job. Still, other models have the starter on top of the engine, in a valley section under the intake. Under this configuration, you need to remove the intake plenum and other components just to gain access to the unit.
On a few models, you may need to remove key components, like a motor mount, to gain access to one or more mounting bolts. Although you may remove some of these components without much problem, you may have to use a particular procedure, like properly supporting the engine.
If you think you need to remove one or more components you don't feel sure how to deal with, consult the service or repair manual for your particular vehicle make and model. You can buy an inexpensive aftermarket repair manual at most auto parts stores or online. Check the Amazon ad farther down.
So make sure you have all the tools necessary for the job before you...
History of the Starter Motor
Although we take starter motors for granted today, the so-called “self-starter” wasn’t even conceived of until several decades after the arrival of the horseless carriage. Early automobiles were often started with hand cranks, but various automakers utilized everything from springs to gunpowder to start their engines. You’re probably also familiar with the archetypal image of a pioneering aviator spinning the prop of his airplane to get it going, and that’s also an example of a human-powered “starter motor.”
Early Engine Starting Mechanisms
Modern internal combustion engines typically lack the ability to self start, and the engines used in the first automobiles were no different. These internal combustion-powered horseless carriages utilized a number of different starting techniques, including:
Hand cranks
Wind up spring devices
Gunpowder cylinders
Hand Crank Starters
Hand cranks were the most common type of engine starters in the early days of the automobile. They were essentially crank handles that were temporarily coupled with the engine crankshaft. The driver would literally “crank the engine” by turning the handle, which would allow the process of internal combustion to begin. After a given number of cranks, the engine would begin to run on its own, and the crank could be removed.
Some hand cranks were permanently installed.
Although hand crank starters were simple and reliable, they suffered from a handful of drawbacks. The main issue with this method of starting an engine is that it is inherently dangerous to the operator. For instance, if an engine kicks back during the cranking process, the operator could be severely injured. Although many of these cranks used overrun mechanism, there was also a potential for injury if the handle continued to turn after the engine started running.
The other main issue with hand crank starters is that it took a certain degree of physical effort to turn them. That meant anyone who lacked the necessary physical strength or dexterity was incapable of starting a vehicle equipped with this type of starter.
Spring-powered Starters
Wind up spring starters were similar to hand crank starters in that they required the operator to “charge” them through a winding action. Instead of directly turning the crank, the spring tension would then be used to start the engine. Although this type of starter fell out of use with the introduction of the electric starter, some modern applications do use spring starters.
Gunpowder Starters
Gunpowder starters work by exploding a small cordite charge inside a combustion chamber. This effectively pushes the...
What is a Starter Motor?
A starter motor is a device that is capable of turning over an internal combustion engine until the process of combustion takes over. This is typically accomplished by providing the necessary mechanical energy to rotate the crankshaft for a given number of cycles. While the starter motor is rotating the crankshaft, the engine begins the process of combustion. The starter is then able to disengage once the engine is running under its own power. Most automotive starter motors are electric, but some applications use pneumatic or hydraulic power.
History of the Starter Motor
In the early days of the horseless carriage, automakers utilized a whole range of different engine starting methods. These first engines were relatively simple. They often had only one or two cylinders, didn’t have electrical systems, and didn’t even compress their fuel mixtures. So while the thought of starting your car the same way you start your lawnmower might sounds incredibly strange today, it was an entirely different matter at the turn of the 20th century.
Before the electric starter motor, many engines used hand cranks.
A lot of early “starter motors” were human powered, in that the initial movement of the crankshaft was literally provided by a human-operated crank. The driver would insert a crank handle into the front of the engine, turn it, and then remove it as soon as the engine engaged.
Other early engine starting techniques used everything from gunpowder to springs with varying degrees of success and failure.
Although the idea of electric starter motors was around prior to the turn of the 20th century, the first production vehicle to have one was the 1912 Cadillac. In addition to starting the engine, this early electric starter also doubled as a generator, which also made the 1912 Cadillac the first production vehicle with all of the parts in place to constitute what we would consider a recognizable electrical system.
Hand cranks were standard equipment on most cars through the 1920s, but the idea of self-starters (and electrical systems) caught on soon enough. Most of these starters used the Bendix drive starter, which remained popular until the 1960s. Unlike Cadillac’s starter/generator units, the Bendix drive was designed to automatically disengage after the engine is running on its own power.
How Do Starter Motors Work?
Modern electric startes share some basic design and operational characteristics.
Internal combustion engines are typically incapable of “self starting,” which means they require some external force to start running. This...
Starting system, Starter motor
Starter motor
A starter is an electric motor that turns over or "cranks" the engine to start it. It consists of a powerful DC (Direct Current) electric motor and the starter solenoid that is attached to the motor (see the picture).
The starter motor is powered by the car battery. To turn over the engine the starter motor requires a very high electric current, which means the battery has to have sufficient power.
Starting system problems are common and not all problems are caused by a faulty starter motor. To find the cause of the problem the starting system must be properly tested. read more below.
Starter solenoid
The starter solenoid works as a powerful electric relay. When activated, it closes the electric circuit and sends the battery power to the starter motor. At the same, the starter solenoid pushes the starter gear forward to mesh it with the engine flywheel (flexplate) ring gear teeth.
A typical starter solenoid has one small connector for the control wire (the white connector in the photo) and two large terminals: one for the positive battery cable and the other for the starter motor (see the diagram below).
Battery cables
The starter motor requires a very high current to turn over the engine, that's why it's connected to the battery with thick (large gauge) cables (see the diagram). The negative (ground) cable connects the "-" battery terminal to the engine cylinder block, close to the starter. The positive cable connects the "+" battery terminal to the starter solenoid.
How a starting system works:
When you turn the ignition key to the START position, the battery voltage goes through the starter control circuit and activates the starter solenoid, which in turn energizes the starter motor. At the same time, the starter solenoid pushes the starter gear forward to mesh it with the engine flywheel (flexplate in an automatic transmission). The flywheel is attached to the engine crankshaft. The starter motor spins, turning over the engine crankshaft allowing the engine to start.
Neutral safety switch
For safety reasons, the starter motor can only be operated when the automatic transmission is in Park or Neutral position; or if the car has a manual transmission, when the clutch pedal is depressed.
To accomplish this, there is a Neutral Safety Switch installed at the automatic transmission shifter mechanism or at the clutch pedal in case of a manual transmission.
Often a transmission range sensor - the part that tells the powertrain computer which...