What problems can you expect from a clutch, and how do you recognize them? For further details, go here: ac clutch not engaging
About the clutch mechanism
Before talking about malfunctions, let's take a closer look at the mechanism itself. "Clutch" in general terms - these are the mechanisms of the car that provide the transfer of torque from the engine to the gearbox, and also allow you to "disengage" this transmission. In other words, cars with a manual transmission (manual transmission) must have a clutch. The robotic gearbox (manual transmission) is also equipped with a clutch, since according to the principle of its operation, the manual transmission is no different from the manual transmission, the only difference is that the clutch is controlled not by the driver, but by the electronics.
The design of automatic transmissions (variator or hydromechanical) is fundamentally different from manual transmissions, so there the transmission of torque is carried out in other ways.
The clutch mechanism consists (simplified) of the following units:
The drive from the clutch pedal directly to the clutch mechanism (sometimes hydraulic and mechanical - with a cable) provides the driver with the ability to control the clutch. For manual transmission, the clutch is driven by an actuator (electric drive), which is activated by the control unit.
The release bearing and the pressure plate (commonly referred to as the "clutch basket") disengage the clutch (that is, break the transmission of torque to the gearbox) when the pedal is depressed.
The driven disc (in common use simply "disc") directly transfers the torque.
Classification of problems
Malfunctions can occur in any of the clutch components, although the largest percentage of problems are associated with the clutch disc as the most intensively working part.
Below is an approximate list of clutch component problems.
Clutch drive:
for systems with a cable - breakage or lengthening of the cable;
for a hydraulic drive - system leaks (fluid leaks, air has entered the system) or a malfunction of the working cylinder;
for manual transmission with an electric drive - failure of the electric motor of the actuator, malfunctions in the software of the control unit.
Release bearing and pressure plate:
wear or damage to the release bearing;
deformation or breakage of the diaphragm spring of the pressure plate;
warping of the pressure plate;
jerks during clutch operation.
Driven disk:
wear or damage to friction linings;
oiling of friction linings;
seizing of the disc hub on the gearbox shaft splines;
Clutch problems are not trivial: they tend to quickly progress from the "car is not behaving" stage to the "car cannot drive" stage. Therefore, any driver is advised to know the primary signs of clutch problems: this often allows you to contact the service in a timely manner, avoiding additional costs for a tow truck or other methods of car delivery .
Clutch faults have quite specific symptoms, of which there are not many. The same symptom can be caused by different clutch components, so the final verdict is made after a detailed study of the problem in the service, but the driver can make a preliminary assessment himself:
the clutch is not completely disengaged (when the pedal is fully depressed): clutch drive, driven disc, pressure disc;
the clutch is not engaged to the end (it “slips” when the pedal is fully released, the engine speed when the gas is pressed “take off” disproportionately to the speed gain): clutch drive, driven disc, pressure plate;
jerks when engaging the clutch: driven disc, pressure plate;
vibration when engaging the clutch (released pedal): driven disc, pressure disc;
noise when disengaging the clutch (pressing the pedal): release bearing.