Dual Mass Flywheel

Received a new 'LUK' dual mass flywheel from Eurocarparts. In short, it looked, and weighed like a piece of pig iron, The plate looked like its been cut out with a hacksaw and the ring gear Mig welded on. Not impressed! I've returned it, and am waiting to see if a better one turns up from a different supplier. Still LUK though as I cannot see any other manufacturers. Any other experiences out there? Cheers

AFAIK LUK make them for Porsche. What does your old flywheel look like? Its meant to be heavy.

Yep - that sounds like a dual mass flywheel.

Hi, Haven't looked at the old one yet. This is all following on from the clutch saga posted on here a couple of weeks ago. (clutch drag + Slip) Car is going into Addspeed tomorrow for a diagnosis, but I reckon it'll be a new clutch. Flywheel occasionally clonks too so reckon I'll need a new one of those. I did think briefly about a lightweight one, but with the engine on 89,000 miles and dire warnings about them from several sources inc Hartech I am minded to play safe until I can do a 'Harv' and build an engine up from scratch. Has anyone had a DMF balanced up with a new clutch I wonder? Hear what your saying Alex. Are they all like that then?

I bit reassuring that LUK make them for Porsche - Thanks wasz

Probably. The manufacturers are hardly going to spend extra cost on manufacturing processes to make them look pretty as it's something the end user is very unlikely to see. the outside diameter of the friction plate is most likely to be just a cast finished (or some crude cutting method) and not 'finished' cut as it'll just add cost to the process and is not necessary. .......and yes they do weigh some.......to stop you stalling the car when you set off :grin:

That....together with the booster spring on the pedal. Something else to remove when I get the time..

James, Yes I have but it was part of a full rebuild at Hartech, M97.1 3.8 but basically the same motor. So I had the benefit of knowing Hartech had inspected the crankshaft and confirmed it was all good. Barry Hart told me his firm had a lot of racing experience with M96 engines (Boxsters and 996s) running lightweight/single mass flywheels and no broken cranks yet. BUT he said always get a specialist to dynamically balance the flywheel, ideally as an assembly with the pressure plate - never rely on the flywheel manufacturer. Also a sprung friction plate to offset the loss of damping. That was 2.5 years ago, 12K miles including some proper a***-out road trips, and no regrets. It seems no more prone to stalling now than it did with the OEM flywheel, maybe the sprung friction plate helps with that as well. I think you'd be right just to renew the DMF and get the clutch all working properly for now, but if you want to make your car more raw and exciting then definitely one to go for if/when you rebuild the engine.

I removed the booster spring but then found there was nothing to keep the clutch pedal on its end stop when not in use, except the master cylinder rod. I didn't like the thought of pre-loading the clutch hydraulics, riding-the-clutch style. I ended up getting a booster spring assembly off ebay for a 986.1 2.7 Boxster, which has a much weaker spring but a smaller housing so not a straight swap into the 996/997 pedal box. I swapped the spring from the Boxster part into my 997 assembly. Worked for me, much better clutch action but still holds the pedal firmly and stops any pre-load. It's still a good idea to just remove the spring first and see how you like it, once the clutch is all fixed and working as it should.

Many thanks for the replies there. Great advice re the booster spring, I'll look into that. Interesting about Hartech having no failures on lightweight flywheels. And your probably right about getting it all working again as standard for now. Lightweight flywheel etc for future projects....... In at Addspeed now. Just waiting to see what the prognosis will be! Cheers

James Do a 'harv' mod :thumb: I like Addspeed so you are in good hands there and I would consider moving to the SMFW now as Swaymars are literally a stones throw from them and could do the proper dynamic balance on the FW & new Sachs cover plate. The SMFW costs less than the DM unit too from my supplier but you will need a sprung centre friction disc. PM me if you need contact details for these parts. You will also reap the benefit of taking lots of weight off the last main crank bearing at the flywheel end. Just my 2p :thumb:

Wise words there Harv, why spend loads on a DMF now when you know it's not want you want and will be swapped out fairly soon. Life's too short. James assuming you can return the DMF you already bought, I'd say follow Harv's advice. When I did mine I bought an Aasco flywheel from a US supplier and that wasn't cheap to start with but the customs etc it was a lot more than a DMF - seemed the only option at the time. The Aasco ones actually seem to be cheaper now than they were in 2015, if I'd found a locally sourced alternative at the time I would've done that.

Ok, hear you both, and makes sense. Harv you have a Pm

Just spoken to David Brown of Swaymar's in Horsham. Doesn't think much of DM FW's does he! £90 to balance a single piece FW and clutch cover.......

Ha ha you've had the DMFW 'conversation' Pm'd you :thumb: