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TR2/3/3A Bleeding the Slave Cylinder

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I see your point Dick about not working without a spring, but the clutch will work without it, but again you need to start out with the SC adjustment set with the guts of SC pushed back into the slave. My belief is when the SC is push out and then let off the SC falls back to an inflexed no pressure spot like disc brakes without a spring. Then pushed again the travel of the rod is enough to the clutch disc off the pressure plate. It sounds wrong, but works without the spring. Remember the adjustment at the slave is like 1/8 of an inch, but again the sc will find a neutral spot like disc brakes and just sit there out of adjustment and function without a spring; there is the danger of the TOB rubbing, but they do not seem to. And yes the spring is supposed to keep everything back so the TOB does not rub. TAKE the spring off and try it

When I first bought my tr3 1972, it did not have spring, but I did not like the slow function of the hydraulic clutch in general and new nothing about a spring then and was comfortably dumb and the clutch worked. I wanted to get second gear rubber and that led me to using and researching a spring, but the clutch still worked with out the spring slower than an American car. Use a spring that barely holds the rod back just a little something.
 
sp53 said:
I see your point Dick about not working without a spring, but the clutch will work without it, but again you need to start out with the SC adjustment set with the guts of SC pushed back into the slave. My belief is when the SC is push out and then let off the SC falls back to an inflexed no pressure spot like disc brakes without a spring. Then pushed again the travel of the rod is enough to the clutch disc off the pressure plate. It sounds wrong, but works without the spring. Remember the adjustment at the slave is like 1/8 of an inch, but again the sc will find a neutral spot like disc brakes and just sit there out of adjustment and function without a spring; there is the danger of the TOB rubbing, but they do not seem to. And yes the spring is supposed to keep everything back so the TOB does not rub. TAKE the spring off and try it

When I first bought my tr3 1972, it did not have spring, but I did not like the slow function of the hydraulic clutch in general and new nothing about a spring then and was comfortably dumb and the clutch worked. I wanted to get second gear rubber and that led me to using and researching a spring, but the clutch still worked with out the spring slower than an American car. Use a spring that barely holds the rod back just a little something.
Click to expand...
Will try without the spring.

Thanks, Dick
 
The clutch will work fine without the slave return spring. The clutch will release at a slightly higher pedal height is all. The spring is not your problem, as many have run for years without the spring after the fork pin sheared. What the slave return spring does is to pull the throw-out bearing away from the clutch so it does not stay in contact with the spinning clutch fingers and wear them down.
 
I had lots of trouble bleeding my clutch as well. I assume you have the Lockheed single master cylinder. I could not get enough fluid to move so the air stayed in the system. What I did was make a flat plate and add a tire valve. Just a couple of pumps with a hand air pump to create just a little pressure and the when the bleeder screw was opened the fluid flowed out. After spending several days pumping and being frustrated, it took less than 5 minutes with this setup. Hope this helps. Cheers, Mike

Hopefully this link to photo works:

> New photo by Michael Graham <
 
If I remember right, he has the early, double cast iron Lockheed master cylinder. He is running the Girling brakes, though. I could be wrong, as Dick tends to post new threads, instead of continuing on the original thread, so I have trouble following what has been done previously.
 
CJD said:
If I remember right, he has the early, double cast iron Lockheed master cylinder. He is running the Girling brakes, though. I could be wrong, as Dick tends to post new threads, instead of continuing on the original thread, so I have trouble following what has been done previously.
Click to expand...
You are right, john, that if I can't find my original post I will start a new one; bad habit!
 
Well guys, i followed Mikes advice, lowered my compressor pressure to about 3#, and blew through the tiny hole in the cap.Between that and my wife, the pedal pusher, we actually got all of the air out of the SC.
New problem, but I'm hoping it is either the wrong length rod or an adjustment. The clutch now only goes about half way down. There is finally movement of the lever but not the full range needed to disengage the clutch
 
That is either air in the system or mis-adjustment at the clutch arm. Of course, make sure you are using the middle hole in the arm to start out. It always works. Later, once you have things working you can experiment with upper and lower holes.
 
Definitely no air in the system as the bleed tube to the SC was solid fluid. I will play with it tomorrow. I have a feeling that the shorter rod is not giving me the play i need to move the lever the full active range for engagement. I am a little baffled why the clutch pedal only goes half way down, it stops very solidly. I have it in the middle hole now.

Dick
 
Have you got the pushrod all the way into the slave cylinder, if you take the pin out and leave the rod free the piston will work its way out to the end of the cylinder, you have to push it all the way in then set the length and make the correct adjustment for free play. Does the clutch peddle go all the way to the floor when the bleed nipple is open? if so the only thing that will stop it is the slave piston being pushed out to the lock ring.

Graham
 
Graham,
After I take the pin out, the screw in the yoke, the piston will work it way out by doing nothing?Do I unhook the spring first? Do I have to push the pedal down for it to come out? Next I open the bleed valve and push the pedal to the floor? Now what? Do I close the bleed valve and see if the SC engages the clutch lever?

If the clutch pedal still stops half way down, how do I cure it from hitting the lock ring? I am sorry if I am probably confusing the issue.

Dick
 
Dick,
Take the spring off unscrew the yoke pin now push hard by hand on the rod so the slave piston goes all the way into the cylinder hold it there and see if the yoke pin will line up with the hole in the clutch lever. That is your starting point to get it set right, if the pedal stops halfway down you have a problem with the clutch release or the clutch plate, that's why I asked if the pedal goes all the way to the floor when the bleed nipple is open to eliminate the master cylinder from your problem.

Graham
 
If all the air is out and the pedal only goes half way down and is hard, then the clutch disc is in backwards. If you look at a disc, they can go in backwards (180 out) with the spring assembly of the disc hitting the flywheel that one inch thick bulge of springs. The spring assembly of the disc needs to be facing into the cab for the clearance, so the fiber of the disc hits the flywheel. I do not know of a way to visually see if the disc is in 180 out other than pulling the trans. I have learn this lesson the hard way myself.
steve
 
O No, hope that's not the case? I haven't put the trans cover or front upholstery in so it should come back out easy. Will explore a little more before Ii remove the trans.
 
Graham H said:
Dick,
Take the spring off unscrew the yoke pin now push hard by hand on the rod so the slave piston goes all the way into the cylinder hold it there and see if the yoke pin will line up with the hole in the clutch lever. That is your starting point to get it set right, if the pedal stops halfway down you have a problem with the clutch release or the clutch plate, that's why I asked if the pedal goes all the way to the floor when the bleed nipple is open to eliminate the master cylinder from your problem.

Graham
Click to expand...
Graham,

I set everything up, pedal would go to the floor with bleeder open. When closed, the pedal goes half way down and the lever moves forward about half it's cycle.
I can;'t believe I have installed the clutch disc backwards! I have installed about 10 new clutches in; TR-2, short door, TR-3, 61 Porsche S-90, 67 911S, 57 T-bird, Karmin Ghia, and two Volkswagens. And now I install one with the disc backwards in my TR-Long Door??
O.K. Graham, John, Steve and Mike. If you guys agree I have screwed up!!!! I will take out the transmission tomorrow.

Boo Hoo, Dick
 
I was going to say, "oh my". The pedal stopping mid travel is not a good thing!

Clutch disc backwards would definitely cause that. The only other thing I can think of is a mis-match in the piston size of the MC vs the SC. I thought the TR2 MC had a smaller piston, though, but I could be wrong. It would have to be a larger MC piston matched to a smaller SC piston. Another possibility is the fork not seated in the proper slot in the release bearing. This would place the release lever at an odd angle that prevents full travel, and would cause issues with the Slave rod length.

Have you checked in and around the pedal for anything preventing full deflection? If it is clear, chances are the tranny will have to come off in this situation.
 
The pedal is clear all the way down. As soon as I opened the SC bleed, it went all the way to the floor. Closed it and it stopped, solid, half way down. But, for the first time, I got the lever to move forward. When the pedal stops, the lever stops moving.

To bad you don't live next door to me! I have removed many a TR transmission. At least I don't have to remove the cover and any carpet in the front. I have put off installing the new OD harness.

Dick Still have problems attaching files. Some will and some won't. The size is always the same?
 
Based on your description, I can't think of anything it could be outside of the clutch housing. I'm afraid the tranny will have to come off.

Bummer.

I know this is a depressing setback...just step back and have a beer to get re-oriented. You are on the home stretch...in the big picture this is just a minor setback to the many great years you will have driving your TR2!
 
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