Problem with acceleration

[Kirk]

Yup, sounds like a slipping clutch. How many miles do you have on the current clutch? The link to Pelican Parts is good. You can get the pressure plate, clutch, and throw out bearing as a kit for about $400. You can simply check the flywheel to see if it's within the serviceable limit, which it probably is. There's no issue really with keeping it as long as it's clean. If not and there's enough material left, get it resurfaced. The replacement for my S at Pelican is $670. It can't hurt to change it, but if it's good, then why throw the money away?

Kirk

[ekam]

I thought we have dual-mass flywheel which is not servicable? That's not if the OP changed to an aftermarket flywheel previously.

[Lil bastard]

Originally Posted by ekam

I thought we have dual-mass flywheel which is not servicable? That's not if the OP changed to an aftermarket flywheel previously.

Generally that's true. The traditional lathe/cutter tends to 'skip' on the flywheel surface leaving it 'choppy' and ruining the cutter. Some shops have done it, but most will not and Porsche does not recommend it. But, the flywheel should be cleaned up assuming it's not warped or hot-spotted.

Just like a brake pad and rotor, the clutch deposits a layer of the friction material on the flywheel surface and it's this friction material-to-friction material contact which makes the best bond. ScotchBrite or even 80 grit sandpaper will clean the old material off the flywheel surface so the new clutch can lay down a new layer as it 'beds-in'.

Originally Posted by Kirk

Yup, sounds like a slipping clutch. How many miles do you have on the current clutch? The link to Pelican Parts is good. You can get the pressure plate, clutch, and throw out bearing as a kit for about $400. You can simply check the flywheel to see if it's within the serviceable limit, which it probably is. There's no issue really with keeping it as long as it's clean. If not and there's enough material left, get it resurfaced. The replacement for my S at Pelican is $670. It can't hurt to change it, but if it's good, then why throw the money away?

Kirk

IMO because if it takes a dump before the next clutch is worn out, or chatters upon reassembly, you have to spend all that money again to get back at it, way cheaper to eat the 600 clams up front. Once a dealer did the belts on my 944, when I got it back it was leaking like the Exxon valdeez. They had ruined the seal doing the repair, when I asked why they didn't replace it they said, you didn't ask us to. Well yeah true enough but at that time I didn't know the propensity of the seal to be damaged and they did but never suggested replacement. They replaced the seal and charged me for the complete job, no responsibility taken for their F^&kup, now their out of business, sweet karma sweet karma..

[Sputter]

I suppose the RMS should be checked and have the updated one installed since the tranny is out. You don't want to re-spend the cash later when the RMS starts to leak.

[edevlin]

"I suppose the RMS should be checked and have the updated one installed since the tranny is out. You don't want to re-spend the cash later when the RMS starts to leak."

I thought that as well when I had my clutch done, but the indi Porsche mechanic I was using said that my RMS seal was completely dry and if it was not leaking not to mess with it. So I did not replace it. I have often wondered if that was the proper strategy. I guess I have put another 30K on the car since the clutch and flywheel were replaced and no leaks so far....

Ed

[Lil bastard]

Originally Posted by Sputter

I suppose the RMS should be checked and have the updated one installed since the tranny is out. You don't want to re-spend the cash later when the RMS starts to leak.

Two schools of thought here; One - replace it while everything is disassembled hoping to save some $.

Second - if the seal is not leaking, leave it alone.

Not all RMS leak prematurely, maybe 20-30%. It's a specialized 'skill' to properly install this seal. If not done properly, the 2nd seal may begin to leak soon after requiring additional expense, not saving it.

[Sputter]

Agreed.

Originally Posted by Lil bastard

Two schools of thought here; One - replace it while everything is disassembled hoping to save some $.

Second - if the seal is not leaking, leave it alone.

Not all RMS leak prematurely, maybe 20-30%. It's a specialized 'skill' to properly install this seal. If not done properly, the 2nd seal may begin to leak soon after requiring additional expense, not saving it.

[Cloudsurfer]

It all depends how far you are on the clutch's last legs. If you have worn through the friction material, you will be scraping the rivets that hold the friction material to the clutch disc across the flywheel, and if this is the case, your flywheel is toast.

With all this apart, I would swap the flywheel out, and in doing so going to a lightweight unit. I suppose if you're lucky and the original flywheel looks great, then just clean it up and take your chances, but I'm not sure I'd want to take the risk.

As to the RMS, I'm inclined to think it's better to replace it while you're looking at it- just make sure whoever installs the new seal does it correctly.

Originally Posted by bmwm750

It all depends how far you are on the clutch's last legs. If you have worn through the friction material, you will be scraping the rivets that hold the friction material to the clutch disc across the flywheel, and if this is the case, your flywheel is toast.

With all this apart, I would swap the flywheel out, and in doing so going to a lightweight unit. I suppose if you're lucky and the original flywheel looks great, then just clean it up and take your chances, but I'm not sure I'd want to take the risk.

As to the RMS, I'm inclined to think it's better to replace it while you're looking at it- just make sure whoever installs the new seal does it correctly.

BMW, does the lightweight flywheel you have make more noise as all articles seem to suggest? If so is it acceptable? Can you tell us all how it changed the feel of your car?

Thanks