Jan 132015

Jaguar made several changes to the clutch slave cylinder during the production of the E-Type which appear to have caused a fair amount of confusion amongst owners, myself included.

The slave cylinder details from the Jaguar literature are:

  • S1 to engine 7E4606 – short 80mm adjustable cylinder (part C21470)
  • S1 from engine 7E4607 – 95mm hydrostatic self-adjusting cylinder (part C24145)
  • S1 from engine 7E18356 (7E55558 for 2+2) – reverted to adjustable cylinder (part C29801)

The difference being the adjustable cylinders require a return spring and bracket to pull the fork back, so the piston is at the mid-point. The hydrostatic, self-adjusting cylinders must not have the return spring fitted. Either type can be fitted to any of the range, so you just need to know which type is fitted to determine whether to fit a return spring.

As a result, the length of the slave cylinder is often used to differentiate between the two types. A 95mm unit was supplied when I ordered a replacement C29801 cylinder and the suppliers assured me it was correct.

I made the assumption, from all the forum discussions on the subject, that I must have a hydrostatic unit and therefore didn’t include the return spring when it was fitted it to the transmission, prior to installing the engine.

It wasn’t until another S2 owner who was going through the same issue was able to confirm the 2nd version of the non-hydrostatic cylinders was 95mm, not 80mm, with the original Lockheed part having markings 3232 648C. This matched the markings on my replacement cylinder and also on the one that had been removed during the dismantling, which was fitted with a spring.

My conclusion was that the return spring will need to be fitted after all. Another recommendation was to replace the mounting stud by 5/8″ UNC x 1″ socket head bolts. This will make later removal easier as access is severely restricted.

So another task to add to the ‘To Do’ list!