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Steve Strain
February 5th, 2007, 12:37 PM
This is really an Alfa issue but I wonder if anyone has the same problem and if so what did they do to solve it?
Any suggestions will be great fully received!

Here is a description (in no particular order).

When maneuvering the Stratos in and out of the garage (or any where for that matter) on light clutch and little/slight throttle the clutch judders (shudders?). However when doing say a “hill start” with the clutch under load it doesn't. The juddering may be worse when reversing.
The judder got so annoying that recently I had a local "European Specialist" replace it (and also fix the oil leaks they were supposed to have fixed some time ago before I put the engine in). They told me it was a faulty clutch.

When the old clutch was replaced it came out dry as was the gearbox input shaft seal and engine rear main seal so I am happy that oil contamination was not the cause. There was clear evidence of high spots on the old friction plate.
The new clutch, pressure plate and bearing are brand new Valeo units and the fly wheel surface was machined.
There must now be high spots on the new friction plate for the juddering to be occurring again but could the real issue be somewhere else?

The clutch is a pull type as per the 164S using with my own (home made) copy of the required engine mounts. The engine mount rubbers are I believe Land Rover gear box (round with a rubber steel sandwich combination). These would be much stiffer than the original cars equivalent but perhaps similar to what the kit prescribes.
The top engine mount is a modified kit component mounted to the rear cross bar (similar location as to the 164 car).
When I rescued the engine from the wreck it had a hydraulic damper in the clutch line. I haven't reused this (in fact I am not really sure what it did). Could this be a contributing reason for it?

I had no such problem with the old Guy Croft beta unit but then it had two gearbox mounts.

Does anyone else have this juddering issue?

Thanks in anticipation

Steve

David May
February 5th, 2007, 01:00 PM
Steve,
If its any consolation, my 24V Corse has always juddered on light throttle, especially reversing. The clutch shows no obvious defects and it happened before and after flywheel lightening. I too never worked out what that damper was for - I suspected noise issues and chucked it too. My 'cure' is to let the thing fully in and reverse in on tickover!
One day i'll have the garage door off again going in too fast!

chris.richard
February 5th, 2007, 03:53 PM
My understanding is that the "damper" slows the engagement slightly if you just drop the clutch, to reduce drive-train strain.

chris.richard
February 5th, 2007, 03:54 PM
PS, mine judders a bit at light engagement too!

Steve Strain
February 5th, 2007, 05:50 PM
I just tried the damper and you are right Chris, it seems to restrict the hydraulic fluid movement. The clutch pedal is now heavier to operate and lacks feel through its travel.
I can see how it might protect the clutch from abuse by letting it engage slower.
I pressed the clutch pedal down a couple of times in rapid succession. On one occasion it felt like the master cylinder hadn't fully returned by the time I pushed it down again.
Good reasons for having and not having it!

Think I will leave the damper in for a while and go and get some gas.

The clutch still shudders a bit.

SUSIT
February 6th, 2007, 09:17 AM
Common problem in subarus, dont know the answer other than new flywheel when you change the clutch and just live with it.
Not a great deal of help