Boxster Flywheel
Author
Discussion

sja

Original Poster:

509 posts

258 months

Friday 11th May 2007
quotequote all
Can I ask what the symptoms would be if your flywheel wasn't functioning correctly on a 2.7 boxster?

An indi has told me mine is on its way out. OPC adamant it is fine.

All I can hear / feel is a slight whistle / whine at about 60 when feathering the throttle in fifth. Clucth has always been on the stiff side, and I feel it has avibration to it but again OPC adamant its all ok.

Cheers

Merritt

1,670 posts

268 months

Friday 11th May 2007
quotequote all
The flywheel is simply a solid steel disc with teeth around the outside (for the starter motor) The clutch housing bolts to the flywheel and the whole lot is attached to the engine crank & as such spins with engine roation. There is nothing on the flywheel to 'malfunction'. Clutches do get stiffer as they get older but if its not slipping and still functions correctly I wouldn't worry.

Steve

Mogulboy

3,066 posts

253 months

Friday 11th May 2007
quotequote all
Not sure I can help but I'm pretty shure it's a dual-mass flywheel and as such, it could malfunction...

sja

Original Poster:

509 posts

258 months

Friday 11th May 2007
quotequote all
Cheers, what can go wrong with it?

tr7v8

7,623 posts

258 months

Friday 11th May 2007
quotequote all
It's effectively 2 pieces the bit that attaches to the crank & the bit the clutch sits on. They are joined with a silicone seal which can separate which leaves it rattling. I suspect that is what the indy has heard.

sja

Original Poster:

509 posts

258 months

Friday 11th May 2007
quotequote all
Thanks that sounds spot on. Wish I could bl**dy hear it though!
Under what curcumstances would you expect it to be at its worst?
Indi said feathered throttle in fifth at about sixty?

Why wouldn't it be when changing gear etc?

toenheel

4,501 posts

257 months

Saturday 12th May 2007
quotequote all
My cars got a vibration at 3000rpm aparently dual mass flywheel related and "apparently" nothing to worry about. If the clutch isnt slipping i wouldnt worry to much. Im pretty sure even if it was minor "OPC" would love to take a look and have your strides down.

hartech

1,929 posts

247 months

Saturday 12th May 2007
quotequote all
The dual mass flywheel is a damper and has springs and silicon/grease inside that damp out small vibrations to give a smoother drive.

As they wear they become loose so they then rattle. This is worse at tickover and low revs but usually goes away when the engine speed rises as there is insuficient time for the mass inside to move forwards and backwards within the worn slack area to hit its own stops as revs increase. The wear increases shock loading to the stops which in turn makes deterioration quite fast. However they rarely prevent you driving the car even when badly worn out but do detract from the smoothness of the car.

The face of the dual mass flywheel will also get scored if a worn clutch plate allows its rivetts to rub on the flywheel face. A new clutch comes with a new pressure plate so one side that bites on the clutch plate is always new with a new clutch but the dual mass flywheel side will always be worn unless it is replaced.

When a new clutch is being fitted it is always worth fitting a new RMS and to do that you remove the flywheel. If at that point it is already noisy and scored it will wear out the new clutch plate more quickly and give poor grab on take up of the clutch - so as it costs no more to fit a new one at that point than the old one - it is a good time to decide to renew the rattly/worn dual mass flywheel which may need doing eventually - before the new clutch wears out - duplicating costs.

It doesn't sound as if yours needs replacing yet so why not wait until the clutch wears out and think about it then.

Baz

johnmaddox

141 posts

242 months

Saturday 12th May 2007
quotequote all
Excellent advice imho. Had my clutch and RMS changed but in my case the flywheel was 100% ok so re-used. Still perfect 18months later.


Edited by johnmaddox on Saturday 12th May 09:29