1989 Ford F350 5.8 EFI. Manual.
Clutch pedal was very stiff and was only able to disengage the clutch at the bottom of its travel. Bled the system, and now the pedal falls to the floor; clutch remains engaged. Relevant info:
- The reservoir is full.
- Master cylinder has no leaks on cab side or firewall side, slave is IN the bell housing and I can't get a good angle to see it or take a picture.
- Followed the entire hydraulic fluid line down to where it runs into the bell housing, no leaks.
- The bleeder nipple was extremely tight and took a lot of force to initially crack. Afterwords, I noticed that the bleeder and hydraulic fluid line running into the housing were jiggling around. I hadn't checked if they were loose prior.
I am open to the possibility that we bled it incorrectly, we did: pedal down, crack bleeder and let fluid run out, close bleeder, pedal up. pump pedal between sets. repeat. The reservoir cap was off and we never let the fluid get too low. The bleeder didn't stick out far enough to get the hose and the wrench over it at the same time. While some air almost certainly got in, I don't suspect it was enough to make the pedal fall straight to the floor given its previous stiffness...
Could one of the hydraulic cylinders need replacement despite the apparent lack of a leak? Could the slave cylinder have gotten disconnected/damaged inside the housing as a result of the torque required to crack the bleeder? Did we bleed it wrong?
EDIT: Got a Mityvac and vacuum bled the lines, but the problem persists. A lot of very dark, sludgey "hydraulic fluid" (or possibly black coffee) was removed. Tranmission is getting dropped in the next few days for a new clutch, we're putting in new master/slave cylinders as well. After seeing the state of the fluid, I suspect one or both cylinders is fouled. I learned recently that if the internal seals fail, the piston can push past the fluid without actually moving any of it. So it can fail without an exterior leak. Will update again soon