Defective Clutch: Central Release Bearing Failure

Hello everyone,

I'm experiencing the same problem for the third time in a short period with my Leon 1M TopSport: the central release bearing has failed, and a large amount of brake fluid is leaking from the clutch bell.

When I bought the car, the workshop invoice stated that a complete new clutch kit (including flywheel, clutch disc, pressure plate, and release bearing) was installed at 172,000 kilometers. I bought the car with 173,000 kilometers and drove a maximum of 1,000 kilometers before the defect first appeared. The central release bearing was replaced, and I continued driving.

It lasted for about 3000 km, then the same thing happened again. I drove it into the garage, pressed the clutch, and splash, the same mess again. This time, the clutch disc, release bearing, pressure plate, and sensor were replaced. The flywheel was still in good condition and had only been installed about 8000 km ago.

It happened again. The clutch had been slipping before, which was strange. I read that many people have this problem and drive with a slipping clutch. If you're careful, it can work without major issues. Ultimately, after another approximately 3,000 km, the central release bearing 'failed' again while I was exiting the highway... After disassembling everything yesterday, I noticed that the flywheel is defective (it can be easily twisted and has 'play' on its longitudinal axis).

Can anyone explain how a flywheel can fail and three release bearings can break in such a short amount of time? Could it be that the faulty flywheel is causing the central release bearing to fail?

I'm really fed up with this... it's a huge hassle every time to take everything apart, and I'm starting to reach my limit.

Best regards,
Marshall.

What does the defect in the central release bearing look like?
It is quite possible that a flywheel of questionable origin will not last very long and may be subject to excessive wear, for example, due to egg-shaped surfaces on the pressure plate bearing.

Do you have any pictures of the defect?

Best regards,

First of all, thank you for the reply!

Okay, as I mentioned before, the flywheel was supposedly installed by the workshop back then. However, I can't tell for sure if it's actually new. Is there a production date on it? It's definitely a Sachs flywheel, and it's also the part that Seat claims is the original one. (The flywheel has the following markings: 2294 003 341 10T15 L1/3)

Unfortunately, I don't have any pictures available right now, and you can't see anything from the outside. When I had the issue the first time, I 'opened' the part and saw that a rubber seal inside was torn or had slipped out of its groove. It wasn't possible to identify it precisely...

Does the flywheel come from a Seat dealership or an independent workshop?

You must be able to tell me approximately where the central release mechanism is defective.
Is the problem caused by the connection, is it broken, or has it been mechanically overstressed?
At what point was the clutch slipping? Can we rule out continuous slipping?

Best regards,

Das wurde in einer freien Werkstatt gemacht. Kosten für die Kupplungsteile lt. Bill approximately €700.

It's basically defective inside the cylinder. I'm not entirely sure how to describe it. But there are no visible signs of mechanical wear on the outside, nothing is broken or anything like that. It's leaking, almost, from the 'ring in the middle.'

The slipping point was roughly about two-thirds of the pedal travel, I'd say. It would slip intermittently between approximately 3000 RPM and 4000 RPM. So, for example, if I was in 4th gear and gave it full throttle at 2500 RPM, it would rev up to 4000 RPM, then it would slip and settle around 3500 or 3800 RPM before continuing to rev normally. It sounded a bit like a CVT transmission on a scooter. But whenever I noticed it, I would ease off the throttle to avoid causing it.

Let's talk about the 110 horsepower diesel engine from your profile.
Then there isn't a central release bearing installed, but rather a standard slave cylinder?

What is the engine code?

Oops, I made a mistake in my profile.

No, I have a 150hp Top Sport model. Engine code: ARL, Transmission code: FMH.

I suspect that one of the errors is causing the defect.
Now you need to check why the clutch is slipping. Is it due to incorrect parts, or are the parts even compatible with the vehicle?
Was everything installed correctly, or are there any issues?

Please contact Sachs and inquire whether this part number is compatible with your vehicle/VIN.

Best regards,

Yes, we had suspected that too...

'Yesterday, I went to the Seat dealer and got the part numbers for my vehicle identification number (VIN). Based on these OEM numbers, there are parts available from both Sachs and LUK. The dealer told me that there was once a retrofit campaign due to a faulty dual-mass flywheel (DMF), but he no longer remembered whether it was a change from Sachs to LUK or vice versa. The question is, is one of these options potentially better than the other? Or would Valeo be a better choice?'

Here's the translation:

'Another question is: Is there a way to tell if any modifications have been made to the car's performance, without using a dynamometer? What are the most common methods? Could that be why the clutch is slipping?'

Hi,
With VCDS, a product from our company, you can determine the performance and are also prepared for future repairs .

'How can I determine the engine's power output without actually driving the vehicle (just with the engine running), and get a truly accurate reading?'

And what about the clutch? Does anyone have any recommendations?

marshall1909 wrote:

How to determine performance without driving (engine running only) and with real accuracy?

"It must be able to drive, without any clutch slippage. KPower doesn't have any supernatural powers or super intelligence built in; the operator is still responsible for that."

'And that's exactly what I was thinking... because if I were to install a standard clutch now, which, as many people know, is already close to its limit even in its standard configuration, and my car has some kind of performance upgrade, then it would all be for nothing again. I once read that people sometimes installed a resistor in PD engines that made the engine control unit (ECU) think that it was injecting too little fuel. Where would something like that be located? Or is it possible to find out?'

marshall1909 wrote:

I once read that people sometimes installed a resistor in PD engines that made the MSG think it was injecting too little fuel. Where could something like that be located? Or is it possible to find out?

You can use VCDS to check the fuel temperature in the engine control unit and see if it is displayed as being unusually high.

Okay, then I should have my colleague take a look at it.

Are there any other reasons why a flywheel might wear out so quickly?

'I also noticed that the valve cover on the rear right side (towards the splash shield) is slightly leaking. Could oil be dripping from there onto the clutch, causing it to slip?'

I'm still not making any progress with my clutch problem. It's likely caused by too much pressure in the system, possibly due to the central release bearing. We suspect that some clearances might be incorrect. However, since the parts are supposedly made for this car (after a lengthy conversation with a service representative from ZF/Sachs, and providing the part numbers), we're less inclined to believe that's the issue. Now I'm wondering if it's possible to fit a different 'clutch bell' or the transmission housing (the part that connects to the clutch and where the central release bearing is mounted) onto the FMH transmission, which would change the clearances. Perhaps someone has done this before...

Another question would be: What could cause excessive pressure in the clutch system? (I actually rule out blocked bleed holes on the master cylinder, because if that were the case, the brake fluid reservoir wouldn't leak either, which is what happened to me after the slave cylinder failed).

Best regards,

Marshall.