Another Clutch Operation Thread

It is "A", the clutch fork pivot lever. I have a new slave and hose, so that's good. The clutch pedal is essentially unconnected because there is not pressure on it in or out. I have a new clutch master, brake master, and new hoses to replace but I started with the clutch slave because I had just taken out the air cleaner anyway. I'll start with some PB blaster and see if anything happens I guess.

Also, is there a trick to getting out the clip holding in the slave hose? It wont slide off.
 
Michael Oxman said:
Also, is there a trick to getting out the clip holding in the slave hose? It wont slide off.
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If grabbing it with pliers doesn’t work, try forcing a flathead screwdriver between the fitting and the bottom of the U in the clip. Then twisting the screwdriver will lever the clip out, or at least start it enough that pliers will work.
 
Michael Oxman said:
It is "A", the clutch fork pivot lever.
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Unfortunately that is the worst of the three possibilities, but try the penetrant first. As mentioned the shaft goes through a plastic bushing (pic below). As odd as it may sound, the shaft can rust to the bush. Same for the pivot on the master cylinders (for the brake and clutch pedals); plastic bush that rusts to the shaft. Penetrant may be enough to free up the shaft and bushing. Especially with some heat (like a hot air gun). If you cannot free it up from the top then as Carl said the trans will need to come out.

Clutch release pivot arm. Black arrow is the part you can see on top of the trans. Red arrow is where it fits through the plastic bushing (below). You can just see at the top of this shaft there is a O-ring (near the arrow tip). That is intended to keep water out, but when it wears it allows corrosion within the bushing. This is where you want to try and get the penetrant into. Blue arrow also pivots in transmission, but no bushing. On all of mine that bottom end didn't seem to stick like the other end does:
4502.jpg

Plastic bushing:
tr056_med.jpg

The flanged ridge on one end sits on the outside of the trans case (i.e. top of the bushing). You might see it under the pivot arm. Try to get the penetrant inside of it.
 
What the inside looks like:

It is that upper section through the bellhousing bushing that will seize. If you can get any movement by soaking with penetrant, just wiggle it very gently back & forth to gradually free it. Forcing it will just make the bushing disintegrate around the shaft, then tyou will have to remove it anyway.
X19-0079a.jpg
 
lookforjoe said:
It is that upper section through the bellhousing bushing that will seize.
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That's the end with the plastic bushing I pictured earlier. Copied from the pic above, the red arrow (below) is where the plastic bush lives, and the blue arrow is the other pivot point that does not have any bushing (metal on metal). Oddly the metal/metal joint does not tend to rust, while the plastic/metal one does.
X19-0079a.jpg
 
Something worth mentioning about this clutch fork lever and pivot points. On all of my trans I've found both pivot points to be rather badly worn. On the upper end the bushing can be (and should be) replaced, although I notice even at that there is wear to the metal shaft where it moves within the bushing. The tension of the throwout bearing action causes it to pull on one side more, causing the shaft to oval. On the other end (without a bushing) the metal bore in the case and the metal shaft wear out. This leaves a lot of slop in the shaft. For the top bushing I've dressed the shaft and replaced the bushing with a slightly smaller ID bronze one to help take up the play. And on the lower end I dressed the shaft, bored out the holes, and installed a bronze bushing. These trans have not been put into use yet so I do not know how well these mods help. Hopefully these changes will also prevent corrosion at those points.
 
Success! I now have play in the pivot arm. I can pull it about an inch or so towards the direction of the slave cylinder (stretching the spring further). I am now confused, though, because the business end of the slave is "connected" to the pivot arm such that to me, the slave should be pushing the arm. Based on the arms movement, it would have to pull. Also, looking at the picture from the original poster, [His picture below], the rod on his slave cylinder is attached to the pivot arm. My rod had nothing on the other end once it went through the lever such that I just slid it out when I removed it. Perhaps I'm missing some hardware? Can someone explain that to me?

X19_0079b.jpg




Also, I pulled the boot off the old slave and look what it looked like inside -- Does anyone remember the Andromeda Strain movie back in 1970s? There was powder in the victims veins where there should have been blood. This was the first thing I thought of when I opened it up.
Powder!.jpg
 

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The slave cylinder pushes the throwout arm when you press down on the pedal to disengage the clutch. That causes the throwout bearing to press down on the fingers of the pressure plate which moves it away from the clutch plate allowing it to be disconnected from the flywheel.

Last year I replaced my slave cylinder that had not been used for over 20 years. It looked similar to your photo. Surprisingly, the fluid in the lines looked pretty good, and it was the only bad hydraulics in the car.
 
dllubin said:
The slave cylinder pushes the throwout arm when you press down on the pedal to disengage the clutch. That causes the throwout bearing to press down on the fingers of the pressure plate which moves it away from the clutch plate allowing it to be disconnected from the flywheel.

Last year I replaced my slave cylinder that had not been used for over 20 years. It looked similar to your photo. Surprisingly, the fluid in the lines looked pretty good, and it was the only bad hydraulics in the car.
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Which is why I'm puzzled - the spring on the lever pulls the lever away from the slave such that the only travel is TOWARDS the slave, which makes no sense.

Here is my original picture - the lever now moves towards the slave such there there is nothing for the slave to push.

Slave with arrow.jpg
 
You have the later spring arrangement, set to reduce the free motion needed to depress the clutch; it holds the throwout bearing against the clutch fingers.
Many people change this to the earlier arrangement, that puts a spring (I don't know if it's the same spring, stronger or weaker) the other way, using the eye on the side of the slave cylinder.
 
Michael Oxman said:
Which is why I'm puzzled - the spring on the lever pulls the lever away from the slave such that the only travel is TOWARDS the slave, which makes no sense.
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When everything is properly adjusted, the slave rod will push the end of the lever arm a bit more than one inch (someone here will have the exact spec so I’m not going to go by memory) towards the bell housing. This movement is resisted by the very powerful springs in the pressure plate.

The little spring on the end of the slave pushrod is just there to keep the tip of the lever arm snug against the end of the pushrod to take a bit of play out of the motion. It’s only there on some later models.

Five speeds also came with a coil spring that pulled the lever arm towards the bell housing. It keeps the release bearing gently touching the pressure plate fingers so that the clutch adjust itself as the disk wears.

Four-speeds came with a similar spring, but it was fastened to a bracket on the slave cylinder so then it pulled the release bearing away from the pressure plate fingers. The idea is that this reduces wear on the release bearing, at the cost of requiring periodic adjustment of the slave free play.

You don’t need either spring. I’d suggest that you get the clutch adjusted properly (a microskosh of rod movement to before the resistance of the pressure plate springs is encountered) with neither installed, see how you like the clutch pedal feel and then try it with both configurations of spring, see if you like one of them more.
 
That's one nasty looking slave cylinder! Soinds like you have it figured out now.

BTW, I went back & fixed all the pic links I could in the thread.
 
Congratulations on getting the lever free. Did the penetrating oil do the trick? Now that it's free, disconnect the large spring and the threaded rod attachments, and work the lever back and forth as far as possible while adding a little more lube (perhaps machine oil) - just to make sure it is cleaned up and moving freely inside the bushing. Also check to see if there is a lot of free play from side to side (as when the pivots are worn). It should move freely but shouldn't have a bunch of 'wiggle' slop.

I totally understand your confusion and questions. Lots of things about these is very odd. I'll try and summarize the excellent relies already posted.

As others have said, on some models (like yours) the large spring is located in the opposite direction from what logic dictates and from what every other car has. As the others stated, there are write ups on how to switch the spring to the other side (using a slightly different spring), or try it with no spring. Personally I prefer having the spring pull the opposite way as yours does. But that requires a couple changes to achieve it - see the referenced link.
As for your other question regarding all the extra stuff you see in the photo - on the very end of that threaded rod. As someone said it also differs on various years. I would not worry about it (I removed it from mine).

Regarding the threaded rod being attached to the lever vs the slave. Actually it isn't really attached to either. It sort of floats between them. If you had the version with the extra hardware on the end of the threaded rod (which you don't), then it would appear to be attached to the lever - although loosely. With your version that end just rests against the lever without any actual 'attachment'. On all versions the other end of that threaded rod just rests against the piston inside the slave (where your sand is living). The hydraulic pressure presses the piston out, which pushes the threaded rod out, which presses on the lever. The reason the threaded rod is threaded is so you can adjust the 'play' between all those items. See the earlier reply about setting the adjustment.

Replacing the clutch master and slave and hoses is a bit of a job. There are several write ups that detail it. One of the biggest issues is getting the line nuts free - they corrode and freeze on much worse that that shaft you just freed. There have been some great tips to help with it. If you don't find them, ask and someone will be able to post a link.
 
lookforjoe said:
That's one nasty looking slave cylinder! Soinds like you have it figured out now.

BTW, I went back & fixed all the pic links I could in the thread.
Click to expand...
Thanks for replacing your pics. You have a lot of well documented repairs on the site!! Youtube mechanics like me are ever grateful.
 
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