The clutch linkage is an arrangement of mechanical and sometimes hydraulic components. A mechanical clutch linkage usually consists of the clutch pedal, a series of linkage rods and arms, or a cable. A hydraulic clutch linkage typically includes a clutch master cylinder and reservoir, a hydraulic line and a slave cylinder. Hydraulic linkages have become increasingly popular because they give the manufacturer the flexibility to increase force at the clutch fork, with fewer space constraints compared to mechanical linkages.
The linkage transmits and multiplies the driver's leg force to the fork of the clutch pressure plate. Whether the linkage is mechanical or hydraulic, the linkage should have some sort of adjustment for clutch play (a certain amount of slack in the clutch linkage).
Check your owner’s manual to find out if your car requires a periodic clutch adjustment. Many of today’s models have self-adjusting clutches that automatically compensate for excessive play in the clutch linkage. Symptoms of an improperly adjusted clutch or problems with the clutch linkage may include a stiff clutch pedal, clutch slippage, premature wear of the throw-out bearing, gear clash when shifting, or a clutch that won’t release. Also, a clutch that may seem OK one minute, but not the next may indicate a loose, worn or missing engine or transmission mount. A qualified technician can quickly determine where the problem lies. Have the clutch problem looked into as soon as possible, because a minor repair may be all that’s required to prevent more serious problems.