The flywheel is a key component of your car’s powertrain, which includes the engine, the transmission, and the other related parts that get the power to the ground.
The powertrain is very important to your car’s acceleration, shifting, and cruising, so it is essential that your flywheel is in good operating condition at all times.
The flywheel is a large, heavy metal disk that mounts to the rear of an engine’s crankshaft. Its purpose is to store rotational energy, as well as to smooth out the fluctuating forces of the individually firing cylinders.
The flywheel has a ring gear around its circumference, which mates with the starter motor when you start your car. The flywheel and the clutch work together to provide a smooth flow of power from your engine to your transmission.
If your car has a manual transmission, it most likely has a flywheel. If your car has an automatic transmission, it does not have a flywheel. In manual transmission vehicles, the flywheel and the clutch perform a similar function to that of the flex plate and the torque convertor in an automatic.
Despite their similar functionality, a flywheel and a flex plate are two completely different types of components, and they are not interchangeable.
Symptoms Of a Bad Flywheel
Here are some of the warning signs of a bad flywheel:
#1. Slipping Gears.
Gear slippage occurs when you change into a new gear and discover that the engine speed (RPM) climbs more quicker than your ground speed. Because the friction surfaces on the flywheel and the pressure plate are both meant to hold the clutch, a slipping flywheel may seem like a slipping clutch.
If oil or grease gets on the flywheel’s friction surface, it affects the clutch’s ability to connect with it and grasp it without sliding, even when the clutch is supposed to be completely engaged (with your foot off of the clutch pedal).
If the gear you’re changing continues sliding, it’ll have a negative influence on your driving skills and eventually ruin your clutch.
#2. Can’t Change Gears.
Problems changing gears is a sure sign of flywheel damage and usually signifies that it’s in terrible shape.
If you can’t change gears or have difficulty doing so, you’re unlikely to be able to drive your car, so it’s time to get prompt advice from a professional.
#3. Burning Smell.
A burning smell from under your vehicle is a sign that your clutch isn’t working correctly or isn’t being used properly.
It comes from clutch plate wear and tear, which can be caused by a warped flywheel causing too much friction and heat. The clutch will likely stop working if you don’t replace your flywheel.
#4. Clutch Vibrations.
As a flywheel degrades, vibrations transmitted through the clutch or multi-plate clutch system may become pronounced. Over time, excessive runout can warp the flywheel’s surface, contributing to these vibrations.
Suppose the flywheel has been subjected to overheating or prolonged use with a worn-out clutch. In that case, irreversible damage may occur, manifesting as a bluish colour, hairline cracks, or smeared metal on the surface.
#5. Inability to Start or Inconsistent Starts.
Damaged teeth on the flywheel can impede its engagement with the starter motor, resulting in difficulties starting the vehicle.
Inconsistent starts or outright failure to start are clear indicators of a potential flywheel issue and prompt attention is crucial to avoid further complications.
#6. Engine Stalling.
An aftermarket flywheel that is too light for the vehicle (or the driver) can make stalling the car much simpler and may cause a choppy idle.
On very light flywheels, just pressing the clutch in may cause the car to stall because the engine RPM reduces too quickly for the ECU to compensate with more air and fuel.
#7. Engine Vibrations with Clutch Engaged.
An imbalanced flywheel can cause the entire engine to tremor, even if the clutch is engaged. If you recently changed the clutch, flywheel, or pressure plate, double-check that all bolts were torqued to spec and that you used thread locker if the factory service manual recommended it.
Because there is a significant amount of energy stored in the flywheel, a loose or disintegrating flywheel while driving is quite dangerous. If everything isn’t balanced and lined up properly, the flywheel might cause the car to shake a lot.
What Causes Damage to a Flywheel
Several factors can contribute to the damage of a flywheel. Here are some common causes:
Friction and Wear.
Continuous engagement and disengagement of the clutch lead to friction between the flywheel and the clutch disc. Over time, this friction can wear down the surface of the flywheel, affecting its performance.
Contamination
Exposure to oil or grease can contaminate the flywheel’s friction surface. This contamination reduces the grip between the flywheel and the clutch, potentially causing slipping and overheating.
Overheating
Excessive heat generated during aggressive driving, prolonged use with a slipping clutch, or other factors can overheat the flywheel. This heat can lead to warping, discolouration and the formation of cracks on the flywheel’s surface.
Clutch Issues
A worn-out or damaged clutch can impact the flywheel’s performance. Clutches that are worn down to the rivets can cause significant damage to the flywheel over time.
Misuse
Improper or unsafe driving techniques, such as riding the clutch or aggressive shifting, can contribute to premature wear and damage to the flywheel.
Moreover, operating the vehicle at consistently high RPM levels, especially bad manual car driving habits can accelerate wear and contribute to flywheel damage.
Imbalanced Components
If the flywheel is not properly balanced or if there are issues with the clutch components, it can lead to vibrations and increased stress on the flywheel, resulting in damage.
Teeth Damage
The teeth on the flywheel that engages with the starter motor can get damaged over time. This damage can make it difficult for the starter motor to engage and your car may take longer to start.
Incorrect Installation
Improper installation of the flywheel or related components can lead to misalignment, imbalance, or inadequate torque, all of which can contribute to flywheel damage.
However, regular maintenance, proper driving techniques and addressing clutch issues promptly can help mitigate some of these factors and prolong the life of the flywheel.
Flywheel Replacement Cost
The cost of replacing a flywheel in a vehicle can vary widely depending on the make and model of the car, the type of flywheel (single-mass or dual-mass), and the labor rates in your area.
On average, you can expect to pay between $400 to $800 for the flywheel part itself. The labor costs for flywheel replacement typically range from $400 to $800 or more, depending on the complexity of the job and the hourly rates of the service center.
In total, the flywheel replacement cost can range from $800 to $1,600 or more. It’s essential to consult with a local mechanic or service center for a more accurate estimate based on your specific vehicle and location.
Additionally, the cost may increase if other components, such as the clutch assembly, need replacement at the same time.