Remote

Hows it going.

I have a 2002 Turbo, 55K miles.

I got the clutch replaced with a standard Porsche clutch a couple of months ago. Ever since the clutch has gone in it has not felt the same as the old one.

Its quite juddery, hard to get the biting point right, if i try and get the car moving with just using the clutch its very difficult, and if theres an incline its near impossible, you have to give it more revs then is normal, its even worse in reverse.

The biting point seems quite high and very small, as you release the clutch slowly theres nothing, then your on the bite zone and it judders, theres no progressive movement of the car as you release the clutch, as said very hard to get it moving without giving it Revs.

The specialist garage are going to take out the gearbox and clutch again to inspect it, however my front left shock has stat leaking so im waiting on coilovers to arrive and they will do it all together.

So my question is has anybody come accross this before?? Or does anybody have any ideas as to what it could be??

Thanks for any help

Macster

The transmission and clutch hardware might have to be removed to determine what's wrong but I'd try to eliminate easier and cheaper to correct problems/issues first.

Has the clutch hydraulic system been properly flushed/bled?

Does the power steering and clutch booster circuit fluid (Pentosin CHF 11S) reservior in the engine compartment have the right level of fluid? Does the second supply tank for the clutch actuating circuit under the cover in the luggage compartment have the right fluid level?

To check the fluid level in the engine compartment the engine should be off and the cold (approx. 20C). Do not spill or get any of this fluid on any hoses (or any surfaces for that matter).

Start the engine and run it at idle for approx. 20 seconds. Turn off the engine. Avoid turning the steering wheel while the engine is idling or after you turn it off.

Remove teh fluid tank cap and wipe off the dipstick. Install the cap and then remove the cap and check the fluid level. It should be in the cold range. If low top up with Pentosin. Do not add too much fluid! With the engine warmed up the fluid level should not exceed the hot max mark.

To check the fluid level in the tank in the luggage compartment, the fluid level visible through the transparent tank should always be between the Min. and Max. marks. If you have to add fluid hold the supply tank by your hand to prevent the tank from being twisted when you remove (or install and tighten) the cap. Do not add fluid until the level is at the lower marking.

If the fluid levels are ok then you need to check the clutch power boost circuit works properly.

Cold start the engine (20C). Run at idle for approx. 20 seconds. Turn off the engine. Depress fully the clutch pedal and release and do this repeatedly until you detect an abrupt rise in pedal pressure. The accumulator is empty. Count the number of times you depress the pedal. The number of times should be 25 or thereabouts. IOWs, the system should work well enough, the accumulator should be able to store enough pressure, to provide the boost for up to 25 clutch pedal depresses before teh clutch pedal effort becomes high.

If you park the car after a drive and let the car sit if after 24 hours the clutch pedal is hard to depress, then at least one of the two valves in the clutch slave cylinder is faulty.

Once the accumulator is empty start the engine and let it idle for approx. 20 seconds. Turn the engine off. Check the clutch's pedal pressure. It should be easy to depress. This confirms the power circuit can replenish the accumulator properly.

If the above needs doing this is a pretty good indication the clutch job was not done properly, unless there is a clear hardware failure of a part.

Sincerely,

Macster.

PorscheDoc

Was the flywheel resurfaced when the clutch was done? Symptoms sound like it was not.

Remote

Thanks alot for that info,

I know the fluid level in the luggage compartiment is correct. I will check your other points now and when i start the car up again and get back to you.

Thanks alot, much appretiated

Remote

Ok i checked the fluid in the engine bay, the car is at 40Degrees as i drove it a few hours ago, the fluid level was at cold.

The fluid in the luggage compartment is good.

I compressed the clutch pedal 26/28 times before it became stiff, i then started the car for 20 seconds, turned it off and the clutch pedal is OK, back to normal.........

Remote

The flywheel was not resurfaced afaik...... when getting a new clutch fitted is this a necacery??

Macster

My interpretation of the info I have at hand is that 20 seconds of idling should be sufficient time for the clutch boost circuit to recharge the accumulator after it has been depleted by the clutch pedal depress test.

If after 20 seconds of engine idling the clutch pedal is still hard to depress this suggests the clutch boost circuit is not working properly and this can account for the clutch behavior your described in your first post.

I have driven my 03 Turbo with a bad accumulator and even a leaking clutch slave cylinder (which in my car's case forced fluid out around the cap of the fluid tank in the luggage area on to the plastic cover over the tank) and the clutch's action remained acceptable. I felt a bit of pulsing through the pedal which was the boost circuit working. The accumulator tends to dampen this pulsing when it is working properly, but other than that and the fact the pedal was hard after the car had sat for only a short time and the fluid was leaking (which is definitely a sign the slave cylinder is bad) the clutch felt ok otherwise.

A tech told me he diagnosed a clutch accumulator bad in another car and the owner reported the clutch had always felt that way and he just assumed that was the way the clutch should feel.

Which suggests perhaps if you can you should try another Turbo (if possible of course) to get some exposure to (hopefully) what a clutch in proper working condition feels like.

Or rely upon a trusted shop and its techs to know what's ok or not. When I have a question about what is right or not right about my Porsches I will stop in at my local Porsche dealer and the service manager will have one of the techs speak to me about my concern or even give the car a brief checkout, sometimes even a test drive. I'm not in there everyday with a concern, but maybe once a year or so. Sometimes the car is in for something else and as a side job I'll bring up this concern and it will be looked into as part of the service. Almost always (in fact I can't think of a time this was not the case) this side job is done free of any labor cost as a goodwill gesture. But I never take this for granted and always offer to pay a half an hour labor fee or whatever is appropriate, though I ask for an estimate just to be sure I'm not signing a blank work order check. But that's just me being overly cautious and from force of habit, not that I feel I can't trust the dealer/service department.

Sincerely,

Macster.

Macster

It is often left up to the judgement of the tech performing the work.

I've never had my Porsche clutches replaced but in other cars as a matter of course, I'd either insist the flywheel be resurfaced, or take the flywheel to a shop and have it resurfaced if I was doing the clutch job myself or even once I resurfaced the flywheel myself when I had access to a Blanchard grinder large enough to grind a flywheel.

If the tech or me doing the clutch job believes the flywheel is not a resurface candidate then I replace it with a new one.

Generally if at all possible it is a good idea to have the FW resurfaced as long as the FW is in otherwise servicable condition, just to help guarantee a good outcome of the clutch job. Nothing ruins a clutch job no matter how good the hardware, the installation, if the FW is grabby due to hard spots or other surface degradation.

Needless to say the FW plays a critical/vital role in proper and acceptable clutch function.

Sincerely,

Macster.

Remote

Thanks again Macster,

I actually edited my post as my clutch was ok after the 20 seconds, in my haste i think i pressed the brake but when i tried it again aand repeated the process the clutch was fine after the 20 seconds.....

Ive had the car since November and drove on the original clutch for approx 3 months, the original clutch felt great, was very easy to drive, suprisingly so infact, however that went on m commute home after a track day and this clutch has been giving me these issues ever since.

Ive also had the slave cylinder go and push out fluid from the resovoir in the luggage compartment, this was done by the same specilist im dealing with now.

The flywheel seemed to be working fine in the original clutch assembly, the clutch just started slipping so i changed it, would i not have been getting the same symtoms im getting now with the old clutch if it was the same flywheel???

Its a very annoying issue

Macster

If the original clutch started slipping then the flywheel is at risk to develop hard spots from the overheating. Provided the rest of the FW is in good shape and the overheating not severe (judgement call) the FW can be resurfaced.

If FW was not resurfaced... it can affect the clutch's behavior. Generally the clutch's engagment is juddery, not as smooth as it would be otherwise. In more severe cases the clutch can slip if the FW friction surface was extremely overheated and hard and slick. The FW can even get worse with hard spots and uneven engagement this can lead to results in a deterioration of the FW's friction surface over time and a passable FW becomes well, no damn good.

Based on what you've posted I believe the accumulator is working ok, the clutch slave cylinder is working ok and the boost circuit is working ok.

However, I note you recently (I guess) had the clutch slave cylinder replaced. Last thing touched is first thing suspected, so before you condemn the FW I'd consider having the clutch hydraulic fluid system flushed/bled according to Porsche directions for this car. The job is not cheap but it is a reasonable thing to consider. And it is a lot cheaper than an unnecessary transmission R&R to gain access to a clutch that is ok other than needing a fluid flush/bleed which of course could have been done with the transmission in the car.

Another thing to consider is the possibility one or more engine/transmission mounts may have gone bad under/from the stress of a track day. If so a bad mount may produce symptoms that mimic a grabby clutch/flywheel.

When (if) you have the clutch hydraulic fluid system flushed/bled at the same time have the tech inspect every engine/tranny/drivetrain mount for any signs of failure.

Sincerely,

Macster.

Kevin

Remote, if your tech did NOT replace the dual mass flywheel or resurface your original dual mass>> you will get clutch chatter. They cut corners and now you "feel
" a clutch that is not operating correctly.

To fix this> you need to replace your dual mass AND clutch disk.. DO NOT allow them to just replace the flywheel. You have to replace the disk.

I can help you out with the parts. I can also reline your new chattering clutch disk.

BTW, where is your pedal engaging at?

Remote

Thanks Kevin,

The clutch is engaging quite high up, the general opinion appears to be that its flywheel related or the clutch is not lined up right..... the judder is very annoying.

Appretiate the offer of help the only problem is a few thousand miles away from you and accross the Atlantic ocean in Ireland....

Kevin

We have FedEx >> Brings the world closer together! Yes, with the pedal up at the top you have a "disk" issue.. That's why I asked.. You can also have a "cracked" rivit in the pressure plate.

Remote

Blast from the past here.

Looking for some more help.

The judder has come back into the car. Basically an oem clutch was fitted and there was some contaminants left on the flywheel causing it to judder. This was cleaned up and clutch felt good. It then developed the same judder a few weeks later. At this stage I was planning on replacing the clutch for a Sachs 890 to handle some extra power and thought I'd be killing two birds with one stone elongating the judder.

So got the clutch fitted along with a LWFW, clutch felt great. However a couple of months later the judder came back.

I had plans to bring the car to the UK for some tuning and geo work, so when I was there the geo place recommended changing the engine mounts. So I asked for some new RSS Tarmac series mounts to be put in when the car was being tuned. This was no problem. The tuning company did however note that my LWFW was extremely noisy, they do numerous LWFW conversions but mine stood out for noise. So they replaced the gearbox oil and were expecting to see some metal particles, however there was none. So when I picked the car up it was fully tuned with new engine mounts and major service. I was delighted as the mounts had appeared to cure the judder. The clutch felt no different to any daily 2litre Volkswagen. I was thrilled.

HOWEVER,

Over the past two weeks the judder has come back and is now worse than ever. Riding the clutch up any sort of incline is horrendous. Car shakes, wants to stall and feels terrible. Reverse is the worst.

The symptoms are worse when the cars warmed up.

Has anybody any ideas??

The new RSS mounts did cure the issue, but now it's back. This is a new clutch and flywheel. Did the new RSS mounts simply manage to hide a bigger issue the gearbox/clutch has, which is now getting bigger preventing the mounts from hiding it any longer........ Or have the mounts givin up the ghost so early (1500 miles since install)

I'm dropping the car into an Indy tomorrow morning for him to replace the mounts with new OEM units to rule that out, after that I'm ordering an oem dual mass and replacing the LWFW (driving me mad)

Anybody had same symptoms??

All help appreciated, sorry for long post.

Cheers,

Mark

Macster

If you have the tranny out to replace the FW be sure you have someone inspect all of the clutch hardware for any signs of a problem.

I recently had my Turbo's RMS replaced and of course the tranny was removed. The clutch hardware looked fine -- the disc showed no appreciable wear -- but the tech did replace the two small needle bearings on the clutch arm pivot shaft.

The clutch felt fine, operated with no untoward behavior at all before the RMS and this has not changed after the RMS. My point is that even without any signs of a problem the tech replaced these needle bearings. I had no objection. I handed the car over with instructions to do what was necessary while the transmission was out of the car.

I have heard that in some cases the fitting of a LWFW can require some modification to the DME engine control programming to address less than satisfactory engine idling/low speed operation arising from the LWFW and its lack of the crankshaft dampener feature and a possible effect on engine idle speed stability. I think one change is the idle speed is raised slightly so the engine runs smoother.

The symptoms you describe suggest to me this is what's going on but how to confirm this and what to do about it I have no idea.

When you go back to the stock FW this might offer some insight.

However, as I touched upon above, and I'll restate this because it is important, it is imperative that with the tranny out all of the clutch hardware be checked for any signs of problems and any questionable items be replaced. The clutch hardware can last a long long time but sometimes a part suffers from premature wear and this can really impact an otherwise good clutch's behavior.