John---The two most likely suspects for the symptoms you describe are:
a) insufficient fluid coming down to the Clutch Slave Cylinder. (Should
push this rod out to 1/2 inch, or so.)
b) Linkage inside the bell housing is broken. Namely the fork pin.
Example a) usually occurs slowly over long periods of clutch use. The
clutch should disengage when the pedal is around and inch from the
floor. When the mechanical linkage at the pedal box wears, the MC
doesn't send enough fluid down to the SC. Lost motion here is easy to
find by lookig and feeling. Repairs are relatively straight forward.
Example b) can be concealed when the broken half of the pin is down in
the clutch operating shaft. You can take the threaded part of the pin
out, as Todd suggested, or give it the "pipe test". (One length of pipe
on the three-holed lever, while pulling the opposite direction on the
fork arm) There should be no lost motion between the fork and shaft when
you change direction with the two pipes. Remember it can take close to
300 lb. of force to disengage the clutch, so don't be timid if you use
the pipe method.
You can add a third cause, if you haven't already checked. That being
air in the clutch hydraulic system.
Clutch operation tends to be "normal" once the car is in motion, with
the synchros doing most of the work in gear changes.
Dick
From:
johncnorth@gmail.com(John North)
Had this problem for a while, convinced myself it was a broken fork pin,
but I have the trannie on the garage floor and I don't see the problem
even now.
Clutch works normally except under two circumstances, one is when I stop
at a light, shift into neutral, let the clutch pedal up and let the
engine idle. Two is when I am travelling at low RPMs in second or
third, like in slow moving traffic. In either of these
circumstances, the clutch looses enough travel to work. It does not
start to release until almost to the floor and when pushed even to the
floor, I cannot shift into another gear. The only way to overcome this
is to turn off the motor, and push the clutch once. The entire
clutch travel is restored, and I can restart the engine and move off
normally. I have become quite adept at doing this while moving, but
it's pretty scary to think about the steering lock when coasting at
30mph. It also means that I must always start the car with the
clutch pedal pressed in, if I don't then the clutch pedal is almost to
the floor before it starts to work and won't allow gears to be selected
So I have the gearbox on the floor. The clutch fork looks fine, is
solid, no movement. It is not cross-drilled, but it is wired and
looks fine to me. Not sure about the brand of TO bearing, but it
moves smoothly on the shaft, however, there is a little play in the
bearing. I'm not positive about the clutch visuals, but I believe I
have the B&B with the blue dot. I have an invoice from the previous
owner that shows the clutch was replaced about 4,000 miles ago
Anyone with ideas about where to look for this problem?
John North
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