Your truck, SUV, or performance car’s torque and power comes from the powertrain they have.
The powertrain consists of the engine and the drivetrain. The drivetrain consists of the front and rear differentials, axles, transfer case, driveshaft, wheels, and transmission.
These components serve the purpose of providing the torque and power your performance car, SUV, or truck to go forward or backward.
One essential component of the powertrain that we left out is the flywheel. If a flywheel fails, it will negatively affect other powertrain components.
Now, you are probably asking: “What does a flywheel do, what the heck is it?” Article will explain three functions of a flywheel, and signs of bad flywheel.
What Is A Flywheel And How Does It Work?
You have probably heard the terms powertrain and drivetrain and have a basic understanding of the fact that they provide the power and torque to propel your vehicle. However, you may not be familiar with all the components of a powertrain. The flywheel is likely a term you don’t recognize, yet your vehicle could not function without it.
A flywheel is a heavy disk of metal that is located in between your engine and the transmission. It is secured with mounting bolts against the back of the crankshaft.
The flywheel is shaped like a coin with teeth around the edge. The teeth will latch onto the starter motor to turn the crankshaft when you start the engine.
Your clutch is mounted onto the back of the flywheel which is why many mechanics wonder if the flywheel is part of the clutch system or not. A flywheel is used toward the back of an engine to increase power and torque, however, you should understand that automatic vehicles do not have flywheels; they have flex plates.
If you own an automatic transmission vehicle, you don’t need to worry about signs of a bad flywheel. They are attached to manual transmissions; however, there are manual transmissions that don’t have flywheels. So, how does a flywheel work?
Now that you know what the flywheel is in a car and if you have or don’t have it in your car and where it’s located, let’s talk about how it works.
As previously stated, the flywheel is located between the engine and the transmission and it increases engine torque and power as a mechanism to store rational energy.
A flywheel has a primary role of smoothing out any fluctuations that result from the combustion process. The moment you start the engine, the flywheel begins to perform its functions.
As I mentioned above, it works in conjunction with the clutch system. When an engine runs, it creates mechanical forces that must operate with the transmission and the powertrain uses the flywheel to connect the two.
The flywheel constantly passes mechanical forces created by the engine onto the designated transmission. This continues until the flywheel does not work correctly.
If you’re thinking, “so what does a flywheel do in a small car?” The flywheel does the same thing on all manual transmissions.
FAQs.
Q: What are the signs of a bad flywheel?
The flywheel is one of those things you do not want to give up without signs on your car. If you do that, it means you are parking your vehicle in a garage until you can replace it. Fortunately, some signs will show before the flywheel goes out. They are:
- Rattling noise when you press or release the clutch pedal.
- Gear goes into neutral or slips out when shifting gears.
- Burning smell from the clutch.
- Regular vibration while driving.
- Car makes strange noise when turn the starter motor.
Q: Does the flywheel constantly spin?
We previously mentioned the flywheel continuously transfers power from the engine to the transmission once the engine is started.
From this you may conclude that the flywheel spins all the time, which is false. The flywheel won’t spin the engine isn’t in gear or is in neutral.
This is because the input that connects to the clutch plate, connected to the pressure plate connected to the flywheel, is free spinning when the vehicle is in neutral.
Q: Can you drive with a bad flywheel?
It appears to be possible to drive with a failed flywheel. It just depends on the severity of the damage. In some instances, a flywheel can leave you stranded in the middle of nowhere.
Additionally, you should note while you may have the option of continuing to drive with a broken flywheel, when a flywheel goes out, there is a possibility of causing failure or damage to other powertrain components in that area, as the flywheel acts as a balancer between the engine and transmission as the crankshaft rotates.
When the flywheel fails to act as a balancer, there will be vibrations as you drive. You will also notice rough idling, which will contribute to the engine not being able to produce peak performance.
Q: Why is flywheel so expensive?
There are two types of flywheels, fixed and dual flywheels. The fixed flywheels are generally affordable for all car owners.
On the contrary, dual flywheels can increase in price greater than a fixed flywheels because of the material to make the part. A standard style of flywheel lasts a lot longer and is very tough to replace.
Q: What happens if the flywheel breaks?
If the flywheel breaks the function of transferring horsepower from the engine to your tranny, you can expect to do some irreplaceable damage.
Additional symptoms include vibrations, rattling noise, gear slippage, hard shifting gear or strange noise turning over the starting motor, etc. In the worst-case scenario, your engine may underperform and lose torque and power altogether.
Q: How much does it cost to resurface a flywheel?
Discoloration or glazing on the flywheel is a sign of wear, and can interfere with how well the flywheel meets the clutch. If it is experiencing wear, the flywheel must be resurfaced.
Resurfacing you flywheel should be approximately $20 to $50 but will not include the mechanic’s service fee.
Q: Does the flywheel need to be replaced with a clutch?
In the case of gear slippage or any indication of a bad clutch – assuming you have a worn clutch disc or something similar, you don’t always need to replace the clutch together with a flywheel.
If you are at high mileage, my recommendation is to simply cut it again whenever you remove the clutch.
Q: How long does it take to machine a flywheel?
There are two methods of resurfacing a flywheel; grinding or cutting. No matter which method is used resurfacing a flywheel should not take any longer than about 3-5 minutes.
The goal of resurface a flywheel is to remove the harder surface and leave a homogeneous and smooth surface.
Q: How many times can you resurface a flywheel?
There is no recommended amount of times to resurface a flywheel, but 1 overall time or 2 is recommended, and no more than that.
In general, machine operators are able to determine the need (or no longer need) of resurfacing a flywheel with just a glance. After all, it is what they do and are trained to do.
Final Word
At this point, you are not wondering what is a flywheel, what it does, and what symptoms to look for when it starts to fail.
Not only do you now have enough information to answer the question “what does a flywheel do”, but you also know what happens if you drive with a bad flywheel. If at any point you notice any of the symptoms above, make sure you go to a mechanic to have them inspect and repair it.