I'm about to tackle the task of replacing the clutch master cyclinder and slave cylinder on my '69 E-Type (ne XKE) 4.2 Series 2 roadster. Having never done this before, I would appreciate any suggestions, guidance and thoughts in moving forward.

Thanking you in advance.

Jay

 

Hi Jay,
It has been a long time since I replaced the clutch master and slave cylinders, but I remember it was not particularly difficult.
Just make sure you have the tools handy. Either drain the fluid reservoir, or pinch the fluid hose with some vicegrips to keep the fluid from draining all over the floor. Personally, I would drain the fluid and replace it with fresh fluid.
As I recall, with the slave cylinder, you may have a bit of difficulty reaching one of the securing bolts. Make sure all hose connections are tight before adding the clutch fluid and bleeding the system. I have always needed a friend, or my wife, pumping the pedal while I worked the bleeding fittings.
Hope this helps. Good luck with your project.
Bill.

 

Jay:

Bill is correct…it’s not a particularly difficult job. Just make sure you spray some penetrating oil onto the hydraulic line fittings the night before and you must, MUST, use a ‘flare nut’ or hydraulic line wrench to loosen the fittings. Buy a cheap set at Harbor Freight if you don’t have one. If you use a regular wrench there’s a very good chance you’ll round off the corners on the fittings and turn a simple job into a major PITA. (ask me how I know).

Good luck!
Alan
N.J.

 

+1 on Alan's comment on spraying some penetrating oil in advance, and on using the correct hydraulic line wrench. It is cheap insurance on keeping the fittings in good condition and saving time.
Bill.

 

Thank you, Bill and Alan.

Can either of you recall the steps through this process?

I appreciate your suggestions - really do.

Jay

 

Hmmm. It has been a long time but I'll take a stab at it.
As Alan suggested, the day before spray some penetrating oil on all the fasteners and fittings that you will be unscrewing. This will make your life easier.
Disconnect the Clutch master cylinder plunger from clutch pedal.
Disconnect the Slave cylinder plunger from the clutch lever at the gearbox bell housing. (You will most likely have to jack up the car for this and reach the slave cylinder from below). Be safe! Use a jack and a jack stand. Never only one.
Disconnect the fluid line to the master clutch master cylinder. Either drain all the existing fluid from the reservoir, pinch the hose so it won't leak, or secure it to one side a little higher than the reservoir. An alternative is to loosen but leave the fluid line connected. Remove the clutch master, remove the fluid line from the old master and transfer to the new one, and re attach the the new master to the car. Do the same to the slave cylinder.
Make sure all securing bolts and fluid fittings are tight.
Reconnect the the master cylinder plunger to the clutch pedal.
Reconnect the slave cylinder plunger to the clutch lever at the gearbox bell housing.
Fill the reservoir with the correct fluid.
Bleed the system at the clutch master cylinder.
Bleed the system at the slave Cylinder until you have a good pedal.
Start the car in a well ventilated area and try putting the car in every gear. If the clutch is doing its job back the car out and take it for a test drive.
Note, you may notice the clutch pedal going soft and loosing some action. Don't panic. Drive it back and bleed the system some more. This time bleed only at the slave cylinder.
Test drive it again.
I think that is about it, but I am sure that all of the Jag E-Type repair manuals have this sequence described in detail and with photos.
Maybe Alan will jump in with anything I may have forgotten.
Have fun.
Bill.

 

There are some subtleties to this job. If you get it wrong, you will wear out the release bearing and you'll have to pull the motor to replace it, so mind what I'm about to tell you.

There were a number of different slave cylinders used during the E-Type run. There's a good chance you'll get the wrong one if you order from a catalog or website, so here's how to tell them apart. First of all, the slave systems fall into two general types: self adjusting or manual adjusting. The FSM refers to the self adjusting version as "hydrostatic", but this term is incorrectly applied and I refuse to use it. Let's see how each works.

The self adjusting version uses a "long" 3" slave which allows 1" of travel in front of the piston and 3/4" behind. It has no external spring. To adjust it, remove the pivot pin in the clutch arm and then push the slave rod all the way to the back of the cylinder. There needs to be 3/4" between the two "eyes' when you do this. If you can't adjust the rod to allow this much space, then discard the rod and fashion a new one by cutting the head off a bolt. Once the adjustment is complete. slide the rod forward and replace the pivot pin. You won't have to adjust again for the life of the parts. The way this system works is that the release bearing always contacts the release plate. The only thing pushing it back are the springs in the clutch. That 3/4" travel allows it to move to the full rest position without causing any pressure on the release bearing. The release bearing will glide along the surface of the release plate, but shouldn't wear, as long as that 3/4" travel doesn't completely close up.

The manual adjusting version can use either the short or long slave. All it needs is about 1" of travel in front of the piston and 1/16" behind. It will have a strong external spring to ensure that the piston fully retracts. The adjustment is done by temporarily releasing the external spring. Then the lever arm towards the front of the car and adjust so that there's about 1/16" of travel. Finally, replace the spring. That's the factory procedure, but there are a few gotchas. Unlike the auto adjusting version, this version depends on the adjustment to keep the release bearing physically off the plate. After 50 or 60 years, there will be a bit of play in the release arm pivots. So 1/16" may just take up the play, without raising the release bearing sufficiently. My suggestion is that once you've completed the adjustment, sight the release bearing through the inspection hole in the bell housing. The adjustment is intended to make sure that there's a 1/16" gap between the bearing and the plate. If there's no gap, you need to to allow more travel. Again, if the rod doesn't give you what you need, just cobble up a custom rod out of a bolt. With this version, you will need to readjust every 10K miles.

 

I recommend changing over to silicon brake fluid while you are at it. That way if you don't get a fitting sealed the first time you won't damage your paint.