Triumph Repair: 1979 Triumph TR7 Clutch issue, clutch pedal, car cold

Question
Howard,

scenerio 1:  "Put the gear box in neutral and start the car cold and put it in reverse gear quickly on level ground with the brake off and just sit there a minute with the clutch down and note if the car tries to creep. Also did you get a crunch? (yes, had a crunch... pretty bad actually... but did not creep.)

Scenerio 2:  "With the engine still running put it back into neutral and let the clutch out. Now depress the clutch pedal and hold it down for 5 seconds and put it in reverse again. Did you get the crunch?"  (yes... loud crunch... not pretty)

Scenerio 3: "Put the car in neutral again and put the pedal down quickly and and put the gearbox in 4th gear and then quickly put it in reverse. Did you get a crunch this time? You should not get a crunch this time."  (Yes... soft/minor crunch...  but a crunch all the same)

I am thinking your recommendation on the pilot bearing is probably it... I have noticed if I "double clutch" it makes a huge difference getting into 1st or R.... also... if I "pump" the clutch 8 - 10 times... then put it in R... no crunch...


Answer
The pilot bearing does not know how many times you pump the clutch so it is not a pilot bearing. The fact that you can pump the pedal tends to indicate that the problem is in the hydraulic system. First thing to do is to look in the slave cylinder to see that there is a spring under the piston, and that the piston and seal slide freely in the bore. The spring keeps the clutch arm and release bearing up against the pressure plate and it removes any free play in that part of the system. No fluid can be compressed so if all of the air is out of the system you have a hard direct movement of the release bearing as soon as the master cylinder piston starts to move. The only free play in the system is the link of the clutch pedal to the master cylinder piston which should not be more than an inch at the end of the pedal.
If the slave cylinder internal spring is not there or the piston is sticking this would account for the 8 to 10 pumps to take up the clearance. Or you still have air in the system.
I don't think the problem is internal at this time.
Howard