Clutch Issues

[twoskies]

Hey. Was driving my truck yesterday. Stopped for a coffee. Got in fired her up and pushed the clutch in. Pedal went all the way to floor and when I took foot off popped about 1/3 of the way up. Then came up all the way. Hard to get in any gear. Finally got in 3 rd and limped home. Hard to get in reverse but did finally go. Took a look at it today and using the previous clutch posts. Everything looked ok. Went out tonite. Fired her up. Clutch seems just like new. 1972 c10. 359/4 bolt. 4 speed. Sm 465 transmission. About 200 miles on putting back together. Any ideas appreciated

[Sheepdip]

Sounds like a pressure plate issue.

[RustyPile]

Yep.. ^^^^^What he said... I'm guessing here, but I'd bet the farm you have a diaphragm style pressure plate. It doesn't have conventional coil springs.. Instead, it depends on centrifugal force to aid in applying pressure . If the free travel isn't adjusted just right, the diaphragm will momentarily "turn wrong-side-out"... IF this is what's going on, the diaphragm will eventually break..

Instead of adjusting for free travel at the pedal when it's "at the top", adjust for free travel "at the bottom".. Meaning adjust the point in the pedal lift so that the clutch starts to engage when the pedal is around 2 inches off the floor.. You'll wind up with some additional pedal travel before the throw-out bearing comes in contact with the pressure plate, but the fingers won't be over extended and the likelihood of the diaphragm inverting itself is negated....

If you have a Long type (coil spring)pressure plate, disregard ALL of the above....