Engine Hokey Cokey

You'll remember I had an issue with my clutch slave cylinder leaking here.  I kept an eye on it, and every now and agin there would be a small puddle of clutch fluid on the floor...  I checked the remote bleed hoses and fittings which all appeared ok, and even having a look inside the bellhousing, it didn't look like the repaired housing or fittings were leaking either.

I concluded that it must be the seal on the shaft that was leaking.  That means engine out again!

Since I have done it before, it isn't too much of a big job.  There are a few bolts that are more tricky than others, and the O2 sensor connectors are a little difficult to reach.  At least all the bolts are new and free from rust.

I stripped the cooling system and front chassis cross brace, removed the exhaust manifolds, starter, alternator, fuel connections and unplugged all the wiring.  This means the engine comes out without too much trouble.  With blocks of wood under the gearbox, and the car on axle stands the engine crane makes short work of removing the engine.

I ordered a new clutch slave cylinder through Gardner Douglas - Genuine one which looks a lot stronger than the Tremec one.  I didn't take a photo of the supplied one, but here are two from the internet (The photos don't look like there is much difference, but side by side they were)

Tremec Slave Cylinder

On inspection of the removed slave cylinder, the central section where the seal moved against, appeared corroded. This means that when the seal moved past that piece, fluid leaked out.  Not sure how this came to be, unless the coating was damaged and the brake fluid corroded the aluminium?  Anyway, I was sure this was the problem.

I removed the quick connect fitting from the new unit and replaced it with my fitting including a dowty washer (bonded sealing washer). 

Engine was then put in, put together with a couple of bolts on the bellhousing and the clutch system bled. I didn't want to fully bolt it all back in case I had a different issue....

I realised that with the new slave cylinder installed, I didn't check the clearance between the slave cylinder and clutch tines to check that the clutch would engage / disengage.  To check this, you have to measure the distance between the clutch tines and the bellhousing, and then the bellhousing to the slave cylinder bearing face.  Then you deduct the two to get the clearance.  You know what that means?  Engine out!

Once out (again), I measured the distance from the slave cylinder bearing face to the bellhousing while still in the car.  I then had to remove the bellhousing and fit it to the removed engine so I could measure that part.

The Macleod twin clutch documentation recommends .100" to .250" of clearance.  I ordered a shim kit from Billy's Speed Shop on eBay.  I then installed the correct shim under the slave cylinder and the engine went back in again!  The clutch was then filled with fluid and bled again.

There are a few tutorials online for how to measure the clerance, but I thought this short video from Kame Trick shows what is required.

I will continue to monitor this to ensure there are no more leaks!