clutch pedal unbelieveably hard depress
 

Hi all,
first time to post here. My buddy asked me to look at his truck for him. Some rats ate the wires going to the ignition box and I fixed. He was pleased and asked if I could make his clutch pedal easier to press. I thought this was strange until I got in the truck. When you press the pedal it is so hard the cab actually raises up on the cab mounts. What the heck?? I replaced all the bushings which were completely wore out and there is no difference. The linkage is not binding anywhere, and the throwout bearing slides freely with the clutch rod removed. Do pressure plates sieze up? I have never seen this problem before, any help would be greatly appreciated.
Drew

Don't know if the design is the same or not so this might not be valid. I had a 67 mustang with the same problem. I would actually bend my linkage when I pressed the pedal. It turned out there is a small bracket screwed to the inside of the bell housing that the throw out fork would pivot against when the pedal was pushed. this had broken and the fork was pivoting against the bell housing. This shifted the pivot point away from the throw out bearing by about 1/2 inch. That was enough change in the geometry to drastically increase the force needed to move the bearing.

I have the same problem with my 77 crew 4x4. I drove this truck about 40,000 miles with the 400 with no problems. Then I swapped in a 460 using a L&L kit with their flywheel, clutch, and pressure plate. Put in a new throw out bearing and pilot bushing to boot. Now the clutch is very hard to depress. no such thing as a smooth shift. My wife can't even begin to drive it. Called L&L and they said to drive it a while. It's been 5,000 miles now & not any better. Please post if you find out anything.

I had this problem with my 77 and my 75 trucks. In both cases, it was because the sleeve on the front of the transmission was dry. This is the sleeve that the throwout bearing rides on and when the grease wears off, the clutch gets very hard to push. But, if you take the pressure off of the bearing, you can move it around on the sleeve easily.

There are 2 ways to fix it. One is to remove the tranny and grease the sleeve again. I think most throwout bearings have a grease fitting on them but you can never get to that fitting when the tranny is installed.

The 2nd way is to use a long Q-tip dipped in grease and grease the sleeve by removing the clutch fork boot an slipping the Q-tip in next to the fork. It takes a few rounds of greasing the sleeve as best you can and then having somebody work the clutch. To grease it this way, you need a flashlight to shine in the shift fork hole so that you can see the sleeve. I have used this method successfully because I got tired of removing transmissions.

Maby one of the 2 rivits in the bell housing that hold the fork in place gave out ?

One thing is for sure. If you don't grease the sleeve, those 2 clutch fork pivot bolts will break off and then it gets even harder to push. I had this happen on my 77 and I basically lost the clutch completely.

update
 

Is the fulcrum that the fork pivots on supposed to be riveted to the bell housing? If so this is the problem. There are two rivets there with sharp edges but the fulcrum came out with the fork when I took it out. I think I just answered my own question, but have never seen this design before and wasn't sure.
Drew

pivot rivets are they a dealer part?
Drew

On my 77, that pivot is bolted to the bellhousing with 2 bolts that go in from the transmission side.