I have fitted an uprated Sachs clutch (flywheel/pressure plate/friction plate/slave cylinder) and it drove well for about 100 miles. The bite was very low though. Without warning (on a hot day?) the clutch went limp preventing gear engagement. Pumping the clutch wasn't enough to recover the pressure. Master cylinder, feed pipe to reservoir and bleed connection down at the bell housing changed as a precaution (slight dampness noted on master cylinder and reservoir feed pipe). Did not fix the issue as the problem persists! No visible leakages anywhere and no fluid level drops. Almost entire clutch system now replaced.
After fresh bleed, engine off clutch feels fine. Engage gear clutch down and car can be pushed.
Start engine (with clutch down) still ok and gears can be engaged with engine running & clutch held down. Clutch released slowly in neutral (not to point of connection to reservoir) and clutch pressure maintained.
*** As soon as clutch released to highest point (i.e. connected to shared brake/clutch reservoir), clutch pressure collapses and gears cannot be engaged.
Has anyone got any ideas pointers as I don't believe the new clutch itself is at fault but obviously it has been changed. It oddly looks to be the reservoir that is dropping the pressure? Breaks are fine though and I can't see the connection.