Had the engine and trans rebuilt about 4 years ago. Gear changes are fine, upshifts/ downshifts. Maybe 1500 miles on rebuilds. This year after storage, clutch engages with pedal not far off the floor. No grinding. I looked through the work invoice and could not fjnd mention of clutch master or slave being replaced or parts listed. Contacted shop and asked them to check on their end if these parts were installed. I dont want to mess up the new clutch parts that were put in. Guidance, please.
First thing I would do is bleed the hydraulics and see if that improves things.
A quick test that might point in that direction… does the engagement change if you rapidly pump the pedal and then try it?
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Has the clutch fluid gone down , look under the pedal box for dampness or trail of crystallized brake fluid ( leak) then bleed . It’s easy to bleed 3 pumps raise the car a bit for access. The extreme cold can cause leaks when inactive
Cheers
Have you adjusted it? It is absolutely REQUIRED to adjust the cutch pushrod every few thousand miles.
Hi Valerie
How much free play is in the clutch pedal when you first press it?
When you press the pedal, its stroke down to the floor is about 8 to 9 inches. But the first half inch to an inch should be easy as the adjusted free play is being taken up. This free play is needed so that the throw out bearing is not in contact with the clutch pressure plate all the time.
You should have a half inch to an inch of free play. If you have more than this, either there is air in the system that needs to be bled out or the clutch free play needs to be adjusted at the clutch slave cylinder
Dennis
69 OTS
Thank you for the great suggestions: I did pump the pedal, no change. Clutch fluid was first thing I checked, along with any leakage in engine compt and footwell. Clutch fluid looks dark, but I didn’t pull a sample to have a better look. Have appt. with shop to check adjustment and probably bleed both brakes and clutch. 4 years on same fluid, probably best to put in clean. The necessity of regular pushrod adjusting is something I was not aware of. Former clutch/before rebuild never changed and so I was unaware this was important to do.
When I depress the clutch pedal, it goes down almost to the floor. It doesn’t require much effort to depress it. I understand about freeplay and the TOB. So this is starting to point to clutch bleed and/or slave adjustment. I have 3 other pedal cars that I drive and my leg and brain may be confused, but I do think this E clutch pedal required more effort than it does now. I’m going to check under the car to see if correct longer CS is there and if it appears to be having issues. I no longer have a safe way to raise the car to do the bleed myself, so will have to wait until mid-June for my appt.
You need to adjust the freeplay at the Slave Cyl push rod IF you are putting miles on the car. Manual probably give you an interval but if you’re a 500-1000 mile a year guy clutch adjustment should a rare evident, unless you have a leak of some kind.
1500 miles seems rather soon if it was set up properly to begin with.
Sounds more like it needs a bleed or replacement part due to a leak.
Valerie-
Slightly off-topic question. What shop did you use for the rebuild? I believe I’m not terribly far from you and it’s difficult to find competent people to work on old Jags, so I’m always interested in recommendations. Feel free to reply by PM if you’d prefer.
It’s definitely time for a flush and adjustment.
Squeezed under the car and checked the Slave. I’m under the impression that the correct slave for this car (69 S2 coupe) s/b the 95mm unit…it appears to be correct. There is quite a length of threads showing.
Found this great comparison shot of the 95mm unit (left) & 80mm (right) :
Still waiting for shop Admin to let me know if they put new Master and/or Slave in. I couldn’t find a reference in their invoice, but I can’t believe they would have done the clutch and NOT replaced these two units.
Valerie,
A few questions/comments:
- I assume that the photo is actually upside down?
- I assume that when the photo was taken, the clutch pedal was not being pressed?
- Is that the speedo cable running from top left to bottom right in the photo?
Could the speedo cable be interfering with the movement of the slave? Assuming the answer to (2) is yes, you have a nice tight spring when the pedal is not pressed, so the slave piston should be fully withdrawn into the cylinder. To adjust the free play, you need to have around 1/16" of movement against the external spring pressure before the release bearing hits the pressure plate. If it is less, you will get excessive release bearing wear. If it is more, you will have to push the clutch pedal down a long way before it starts to operate the clutch (as you are reporting). It may be easier to test the free play if you temporarily remove the spring, though I don’t always find it necessary.
That rusty old thing has not been replaced. They do develop a nice patina, but that is way past that.
With the external returns sping, it does not matter which cylinder you have…
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David, good questions!
- Light was coming from the bottom of photo, so yes, upside down.
- Yes, pedal NOT being pressed.
- No, not the speedo cable, some kind of drainage tube??? Any ideas?
So, best to replace slave, and the spring as well? If that is the Slave cyl that I had replaced many years ago, it’s now 26 years old. I’ll bet the bore is shot.
To my eyes, and given the photo is upside down, that rust looks to be originating from somewhere above the slave cylinder. It doesn’t look to be coming from within the cylinder.
I’m wondering if the inlet hydraulic line to the slave cylinder is leaking at the union, or if the casting is porous? Can’t think what else might be causing that. Are you losing fluid?
I wouldn’t be in such a hurry to throw this away for a new one - it looks pretty superficial surface rust to me. Should clean up fine.
All the moisture in the system ends up in the slave cylinder. The bore gets corroded quickly. I think changing the fluid more regularly would help. I tried to get the stainless cylinder, but it was a three month back order.
That return spring looks way too light.
Make sure that after you pump the clutch once that you can’t then push the clutch lever more into the slave. If you can, get a stronger spring.
Correct, but suggest you stay with the same size cylinder that’s now on the car which appears to be the 95mm (3 3/4") unit otherwise you’ll need to change the length of the push rod too. I’ve used the all stainless steel slave cylinder supplied by Hye-Dra-Cyl with good results … and no rust! No affiliation other than being a satisfied customer. Good luck getting this problem sorted out. 
I’m going to guess that the slave was replaced. All my new cast parts, clutch slave, water pump, etc. are rusting very quickly. I’d assumed incorrectly that they were painted.
That spring looks just like my new one. It is not very strong. I think the original springs were thicker.
Dave