The clutch is an essential component of a car’s transmission, responsible for transferring power from the engine to the wheels. A properly functioning clutch will provide years of trouble-free service, but when it starts to wear out, it can cause all sorts of problems.
One of the most common symptoms of a failing clutch is difficulty shifting gears. But in some other cases, your clutch pedal can feel as hard as a rock. If your clutch feels as hard as a rock, most probable causes are; a bad pivot ball, a bad cross shaft, or a worn clutch plate.
How Does Vehicle Clutch Work?
The clutch pedal is the pedal on the left side of the car that controls the clutch. The clutch is what allows you to change gears. When you push down on the clutch pedal, it disengages the clutch, which means that the engine and wheels are no longer connected. This allows you to change gears. When you let go of the pedal, the clutch engages and connects the engine and wheels again.
The clutch pedal has a few different parts. The first part is the pedal itself. This is usually made of metal or plastic. The second part is the cable that goes from the pedal to the clutch. The third part is the master cylinder. The fourth part is the slave cylinder. These are all located under the hood of the car.
The clutch pedal is usually connected to the clutch cable by a pin. The pin goes through a hole in the pedal and is held in place by a nut. The nut can be tightened or loosened to adjust the amount of play in the pedal. The play is what allows you to engage and disengage the clutch without having to push down too hard on the pedal.
The master cylinder is a small reservoir that holds brake fluid. The slave cylinder is attached to the transmission.
When you push down on the clutch pedal, it pushes fluid from the master cylinder into the slave cylinder. This pressure forces the slave cylinder to move, which disengages the clutch.
When you let go of the pedal, the pressure is released, and the slave cylinder returns to its original position, engaging the clutch.
The final part of the clutch pedal assembly is the return spring. This spring is what keeps the pedal in the up position when you’re not using it. The return spring is under a lot of tension, so be careful when removing it. If it isn’t installed properly, it can cause the pedal to get stuck in the down position.
1. Faulty Throwout Bearing
A throwout bearing also called a clutch release bearing, is a type of bearings used in automobiles equipped with 7 speed manual transmissions to engage or disengage the clutch.
It sits between the pressure plate and the transmission input shaft. When the clutch pedal is depressed, it presses the throwout bearing against the pressure plate, which disengages the engine from the transmission without turning off the engine.
If you have a faulty throwout bearing, then it won’t press against the clutch pressure plates. This will cause you to push the clutch harder in order to depress the clutch fully.
Other signs of faulty throwout bearing include:
- Grinding or squealing noise when the clutch is disengaged
- Difficulty shifting gears
- A burning smell coming from the clutch area
- Visible wear or damage on throwout bearing or related components
2. Blocked Clutch Lines
A clutch line is a type of hose that is used to connect the clutch master cylinder to the slave cylinder. This line allows fluid to flow from the master cylinder to the slave cylinder, which in turn activates the clutch.
Clutch lines can be made from a variety of materials, but most are made from heavy-duty rubber and metal braid allowing the hose to flex as the gearbox, engine, and the manual transmission shift when driving.
If your clutch pedal feels hard as a rock or is very spongy, then the clutch lines could be blocked. You can troubleshoot this problem by manually inspecting all the hydraulic systems of the clutch, and clear any blockages.
3. Failing Clutch Master Cylinder
The clutch master cylinder is a hydraulic device that actuates the clutch pedal in a vehicle. It converts physical force into hydraulic pressure using a piston and cylinder arrangement, and uses this pressure to push fluid through a small diameter pipe to the slave cylinder, which is located at the other end of the system.
The advantage of this design is that it amplifies the force applied to the pedal by the driver’s foot, making it easier to engage and disengage the clutch. In addition, it allows for a much smaller and lighter overall system than would be possible with a purely mechanical setup.
Suppose your clutch pedal feels like it’s getting harder to press or isn’t returning to its normal position as quickly as it used to. In that case, that could also be a sign of a problem with the clutch master cylinder not being able to provide enough pressure to push clutch fluid through the system.
Other signs of failing clutch master cylinder
- A soft or spongy feeling when you press the clutch pedal is a sign that your clutch master cylinder might be failing.
- Another symptom of a failing clutch master cylinder is if you notice fluid leaks coming from around the pedal or from under the hood of your car.
- If your car starts making grinding or chattering noises when you try to shift gears that could also indicate a problem with the clutch master cylinder.
- Finally, if your car seems to be having trouble shifting gears or going into gear at all, that could be a sign that the clutch master cylinder is failing and needs to be replaced.
4. Damaged Clutch Assist
Clutch assist is a system that helps to engage and disengage the clutch. It is often used in vehicles with manual transmissions, and can be either hydraulic or electronic. This system can make it easier for the driver to operate the clutch, and can help to prevent damage to the clutch system.
The clutch assists are simply vacuums, and with time these vacuum assists can get blocked hence resulting to failure to boost the clutch system. When this system gets blocked, the clutch will feel harder to depress making it almost impossible to shift gears.
5. Faulty Clutch Pivot Ball
A clutch pivot ball is a small, round metal ball that is located at the point where the clutch pedal attaches to the mechanism that activates the clutch.
This ball helps to provide a smooth, consistent feel when depressing the pedal and ensures that the pedal returns to its original position after being released.
Over time, however, the pivot ball can become worn or damaged, which can cause the pedal to feel stiff or sticky or even prevent the pedal from returning to its original position.
Replacing the pivot ball is a relatively simple process that can be completed in just a few minutes.
6. Worn-out Clutch Plate
A clutch plate is a pressure plate that is used to engage and disengage the engine from the transmission. The clutch plate is what allows the engine to be disconnected from the drivetrain so that the car can come to a stop without stalling.
The clutch plate is located between the flywheel and the pressure plate. It is made of metal and has a friction surface that faces the flywheel. When the clutch pedal is depressed, it pushes on the release bearing which in turn pushes on the pressure plate. This action releases the pressure on the clutch disc, allowing it to spin freely.
While the clutch plate is a vital part of the car’s drive train, it is not without its problems. One of the most common issues is that the friction surface can become worn down over time, making it less effective at engaging and disengaging the engine from the transmission.
If you notice any of the following signs, it’s time to have your clutch plate checked by a mechanic.
- The clutch pedal feels “spongy” or soft when depressed.
- It isn’t easy to shift gears, especially from first to second gear.
- The engine speed increases, but the vehicle doesn’t move as quickly as it should.
- You hear a grinding noise when shifting gears.
Hi I’m Marshall based in 1478 Doctors Drive Santa Monica, CA. I’m your DIY Car Repairman with more than 5 years experience in automobile repair, a skill I learned from my old man.
I started this blog to share my experience on both simple and technical aspects of your car.