Triumph Repair: CLUTCH NOT DISENGAGING

Question
Hello Mr. Fitzcharles,
Its been about 2 years since you advised me on my Intake problems, you solved them all, everything was running great until "it" decided not to come out of gear as I was driving down the road, quite the experience to say the least.
I rebuilt both master and slave cylinders, but problem still existed. I questioned my rebuilds and bought new cylinders, but still will not release the clutch. I bled them repeatedly and measured the push rod's travel distance by putting a screwdriver against the back of the fork through the vent hole in the rear of housing. I measure about 5/8" travel in total. When the slave cylinder is removed an the push rod fully engaged by hand it protrudes about 3/8"from the casing. I'm wondering if the pressure plate or the fork are the problem, the clutch and plate are new less than 5,000 miles.
Do you have any suggestions before I do a tear down?
Thank You again for all your help in the past and for your time concerning this matter.

Rich   
1980 TR7 5 speed

Answer
Hi Rich,

To test the hydraulic system do this, First confirm that there is a little free play in the clutch peddle. (1/2" to 1") Then push the clutch peddle down with your hand. It should be hard to push right away and feel about the same resistence all the way to the floor.

If it does that, then have the car on a flat surface and put it in 4th gear engine NOT running. and depress the clutch to the floor and have someone rock the car forward and backwards with the hood open so they can see if the engine is rotating or not. It should NOT turn the engine. If it does turn the engine put the car in 1st gear and try it again. Rocking the car should try to turn the engine but usually can't turn it much. Also try reverse to see that the engine tries to turn backwards. This is a test of the gearbox and shift linkage.

Now, providing the car has not been setting for any length of time. And you found that the engine does rotate with the clutch depressed and the peddle does feel normal, then there is an internal clutch problem. However if the car has been setting for some time and not driven then you may just have a stuck clutch and no mechanical failure.

However, your statement that it happened while you were driving it. So note if the shift lever feels normal with the engine off. If the clutch peddle and the shift lever feels normal with the engine off, then you need to pull the engine and examine the clutch and the pilot bearing in the flywheel to be sure it is not seized on the input shaft. Then remove the clutch pressure plate and examine the disk and note if the disk slides freely on the spline of the input shaft (1st motion shaft) A disk that sticks on the shaft spline will stay tight against the flywheel when the pressure plate is in the release position.

Let me know what you find.

Howard