Hi,
I have a S5 FC-Turbo where I have replaced the Engine. After putting it all together and getting the engine to run I wanted to take it for a test-drive.

But with the engine running, I wasn't able to shift into any gear. A quick test revealed that the clutch partly disengages: With e-brake on and a gear in I can start with a pressed clutch pedal, but not without.

I checked the master and slave cylinder and they are both dry and not leaking. I bleed the clutch fluid and checked if the slave is moving the clutch-fork freely. Everything seems to be in order on this side.

So this weekend we took out the transmission, to check the inside of the clutch. But the inside seems to be okay as well. There is nothing missing and the bearings are still working.

Any idea, what I can check or where the error may be?

 

Did the flywheel come with the new engine or is it your original?

 

have you put a spigot Bering in the crank

 

The part is also known as a pilot bearing.

 

The flywheel did come with the new engine.

I haven't replaced the pilot bearing. Is there a way to test it, if it is still good?

 

Which way around is the clutch disk?
You need the 'hump' in the center to face the diff.

A stuffed spigot bearing can be tested with a finger. Rotate the inner race by hand, and feel for lumps bumps and general shittyness.
If it feels gritty, dry or crap - change it. I generally do the thrust and spigot bearings when i do the clutch.

I had this issue once in my old ford. The firewall was flexing so badly that i wasnt getting full stroke on the clutch. However it was cable, not hydraulic.

You'll have to put the box back in to do this test:

Get a mate to slowly stand on the clutch peddle with you under the car.
Check for the clutch line ballooning, and make note of how far the slave extends. (White paint pen is good for marking on the bellhousing)
Now get your mate to stamp on the clutch very quickly, make note of where the slave extends to. (be quick about it)
Get your mate to hold the clutch down for a min or so, see if the slave slowly retracts back.

If your slave extends more when stamping on the clutch, than slowly stepping on it - thats an indicator that the master seals are on their way out.
If your clutch line baloons, replace it.
If your slave slowly retracts back, then your master seals arn't holding - time to get the master serviced.

 

I allready tried the master/slave for leaks. I put a weight on the clutch overnight and checked if the slave goes back or if fluid leaks somewhere.

I will check the pilot bearing this evening.
What do you mean with the "hump" in the center?

 

If you look at a clutch disk from the side, the center section will poke out one side of the disk more than the other.
The side with more poking out needs to face the diff, otherwise it wont disengage properly.