Clutch Problem?

[williams]

When I lift my foot from the clutch pedal in neutral. There is a very noticeable rattle from down below.
Depress clutch again and the noise disappears. Clutch appears fine otherwise with none of the usual signs of wear.
No doubt I will get Autostrasse to take a look but has anyone come across this before?

 

[carlmthompson]

If it's coming from the back, it's the idler bearing - mine does the same, and was caused by lack of use over last year. Using it for a few hundred miles to Edinburgh and back noticably decreased the noise.....

Of course, yours might just be plain knackered[]

 

[williams]

Your sympathy is much appreciated! You may be right though, apart from Le Mans last year and a few local
excursions the car has not been used nearly enough. Prior to this was laid up for three years. I suppose a belt change would also be due.
Paul

 

[Diver944]

Definitely the idler gear in the gearbox - they all do that sir [] (well they do as they age anyway)

 

[williams]

Thanks chaps. Is this anything to worry about?

 

[944Turbo]

Wel my clutch release bearing rattles and clonks, i am going to get it done when the clutch goes been waiting 80,000 miles so far - probably just cursed it
Tony

 

[A5DSR]

I wrote to Porsche UK about this ideling gear noise from the rear when I bought my 2.7 back in 1990.
They said it was normal behaviuor and nothing to worry about. It still doing it today, 16 years and 80K miles later!
I could post the reply if I can find it.
Saying that the noise isn't really noticable inside the car with the door shut, only from the outside.

Darren.

 

[Diver944]

Got me stumped [&:]

Does sound like it's in the driveline/ clutch somewhere if it goes away with clutch pressed down.

It could be worth bleeding the clutch fluid as it's the simplest thing to do, but I don't see how an air pocket would cause a vibration. Has the level in the reservoir dropped at all?

 

[944cabby]

It's just a little below the max level.

 

[944turboS]

Clutch release bearing?

 

[rob944s]

How are you getting on with your new noise? update please! i would say to have a look at my thread "Torque Tube bearings gone help needed" it sounds to me definatly drivetrain, and dipping the clutch will release the torque shaft and allow it to freespin in the tube with no pressure on the bearings, have a look at the attachment to see whats inside the torque tube.................

 

[944cabby]

Well it's still there, no better or worse but i'm going to check it out over the easter break starting with each of the wheel bearings as a process of elimination and also do the clutch fluid change as diver suggests.
It's definately from the front not the rear though.

 

[peanut]

I had 3x wheel bearings go on my 86 lux and 89 S2 . Once you know what the problem is its easy to diagnose from the noise .
If the noise/vibration lessens when depresing the clutch then obviously it has nothing to do with wheel bearings

Best way of eliminating wheel bearings in my experience is to get someone to drive your car drive at a steady speed round a long right bend and then a left hand bend.
Listen carefully. If it is a wheel bearing you will notice that the noise /vibration increases as you enter one bend but decreases in the other direction. This is due to an increased pressure on the wheel bearing on one direction but less pressure in the other directon.
If the left hand bend increases the noise it is likely that the worn bearing is on the drivers side and vice versa.

A worn/dry clutch thrust bearing noise will reduce when depressing the clutch but you would hear nothing whilst driving and it definitly would not cause any vibration in motion.Take a look under the car there is a clutch inspection plate you can use a torch to inspect see if there is a load of rusty dust in the housing indicating the thrust is dry and breaking up

My guess would be the clutch plate itself especially if you have been dropping the clutch a lot for wheel spins etc. If the clutch plate has the rubber inserts then they may have broken and the resultant misalighment would cause a whining rumble noise that you describe. Sounds and feels just like propshaft/gearbox/ drive shaft bearings .You would also notice a slight clonk as the drive is taken up on pulling away .
Try driving along at a steady 30-40mph and then booting it then de-accelerating see if there is any noticable cloncking sounds in the drive train.
If this is the problem eventually the clutch will fail and you'll lose all drive.

Also you could jack up the pass side at the rear and stick the car in 1st. Turn the drive wheel back and forth and see if there is any noticable play in the drive train.

 

[rob944s]

nice one nick, sounds like pretty good advice to me, lets hope he can get to the bottom of it without too much expence..... 944cabby how are you doing did you change the ps fluid? and do You have a first name? couldn`t find in your profile!!!!!!!!!!!!!!!