How are clutch master cylinder issues diagnosed?
Clutch master cylinder failure is most evident when the slave cylinder actuates properly, but pressure bleeds off while holding the clutch pedal. This means, that as the clutch pedal is held, the slave cylinder will slowly allow the clutch to engage, but is free of leaks, and in good condition. Normally, a leaking clutch master cylinder is a give-away. In most cases it is recommended to change the slave cylinder at the same time, as the master cylinder failing may be an indication of overall system condition. It is much more economical to replace both during the same service.

How is a clutch master cylinder replaced?
Replacing the clutch master cylinder requires that the fluid from the system is drained. Also, it is normally recommended to replace the clutch slave cylinder at the sale time. After draining the system of fluid, the slave cylinder and master cylinder will be removed from the vehicle by disconnecting the slave cylinder from the transmission bell housing, and removing the master cylinder from the firewall. The clutch hydraulic line should be removed with the slave cylinder and clutch master cylinder. Once separated from the vehicle, the new components will be fitted, and the line replaced if necessary. Installation is the reverse of removal, and once the system is in place, the system must be bled of air, and tested.
RepairPal Recommendations for clutch master cylinder issues
We recommend OEM quality or better replacement parts for the clutch hydraulic system. Inferior products can lead to repeated repairs, and result in greater costs in the future.
What to look out for when dealing with clutch master cylinder issues