Help - Search - Members - Calendar
Full Version: Dual Mass Flywheel Or Single Mass Flywheel Opinions Please
Ford Owners Club - Ford Forums > Ford Models > Ford Focus Club
Kadan II

I recently had the misfortune of the dual mass flywheel on my 1.8 tdci collapsing and I wondered about changing to solid mass flywheel. Anybody out there tried this???

Thought Please

artscot79
Many taxis do it and it was a common vw thing to do however the result is a far noisier engine heavier noisier gearbox and i mean heavy as in the clutch pedals a lit stiffer its fine for a taxi but i wouldn't suggest doing it to an every day driver like youres
Mike77
As above, its dual mass for a reason.....
flying clutchman

I've fitted smf kits to a variety of cars and vans and only one (a BMW 318d) suffered any adverse effects. I have fitted loads to transits (RWD and FWD)  and a few peugeots and a laguna as well as the bmw I mentioned. There's absolutely no reason why the pedal should become heavier as the operating system remains the same (hydraulic csc). There's not much cost difference on the focus so it's just as easy to fit another dmf. Taxi drivers tend to go for the smf as it means less parts to be replace at the next clutch change. For the normal motorist that's not an issue.

artscot79

the guys taxi sits over the road and he complained that from a dual to single it was awful ive driven it briefly and its not pleasant very noisy and very rough yet when the dmf was reinstated it was like driving a new car

 

When you're engine is running, it isn't a smooth motion, especially a 4
cylinder diesel. This can be easily seen through the scope pattern of a
crank sensor. As a cylinder fires, the waves will get closer together as
the crank spins that bit faster and spread out again as it loses it's
inertia. Coincedently, this is how an EMS spots a misfire, because the
waves stay constant rather than contract and expand.

So we can
translate this to the crank pulley and flywheel. These objects speed up
and slow down along with the crank, as they're bolted to it. Early
diesels used rubber mounted crank pulleys. This stopped excessive belt
oscilation (watch an auxilary belt tensioner in slow motion) and acted a
bit on the crank. A crank pulley isn't very big or heavy though, so
it's force doesn't have much impact on the engine.

A flywheel
however, is very heavy. It's also very wide, meaning it carrys and lot
of rotation mass and torque. So when this starts oscilating with the
crank, it creates a much larger resonation. Of course, you're thinking
that flywheels are there to help an engine keep it's rotation and
smoothness. In a nice smooth petrol engine, yes, but they don't have to
deal with these massive oscilations.

So a dual mass flywheel,
which is basically 2 flywheels which are attached by springs, helps by
using the spring travel to damped those oscilations to the drivetrain.
As the engine side spins, that quick accerlation of the pistion is taken
up by the springs, and transfered to the gearbox side. This means the
gearbox side spins a lot more smoothly, helping to keep the drivetrain
intact and stop unwanted vibrations and resonations.

I believe it was originally invented by BMW and Valeo in the 80's, so it's hardly new tech. I think E30 318is' came with them.

I`ve heard horror stories about broken crankshafts,cracked bell
housings,vibrations, on engines that have had the DMF replaced with a
solid kit from many forums it was common to have vw fitted with a single flywheel and no one who had it done kept it they reverted back to the original set up i only persoanlly knew of one who had a cracked housing that was diagnosed as caused by the smf so vw wanted nothing to do with it but i dont fit them i agree many still have the conversion done but on vans you dont care if its noisy and you cant tell the difference on a renault anyway lol

FOCA

After the DMF broke up on my power tuned Mondeo due to the increased bottom end torque and age, i considered fitting another DMF, (rather than an SMF) especially due to the "Horror stories" floating about the net including the clutch disintegrating, snapped crankshafts/ gearboxes - the car imploding and transporting you to a parralel universe where petrol costs 10p a gallon, there are no speed limits and eveyone drives V8s (ok not the last bit :lol: )

 

I spoke to a company that supplies SMFs and DMFs, the chap explained that a propery balanced, matched SMF is in many ways better than a DMF, and should last longer, and many of the problems are due to them being cheap, imbalanced or mis- matched or fitted wrongly - often the "horror stories" are spread by people who have never fitted an SMF

 

I ordered a balanced SMF (solid flywheel) carbon fiber/ kevlar clutch with sprung plate (this is important to put the "give" back in when the DMF is removed) heavy- duty back plate and 30% upgraded clamping force , this makes the clutch pedal slightly heavier,  but its well- weighted

 

After the SMF was fitted the car was a lot smoother (compared to the "knacked" DMF ) the clutch pedal was a lot more positive and the gearchanges slicker, (i run a quick/ short- shifter) the car felt quicker too (the DMF was probably soaking up a lot of power)

 

Refinment is not quite as good as a new DMF, but much better than an old, worn DMF, the SMF/ solid flywheel will not wear out, the carbon clutch is supposed to be good for 400Hp (so a bit of tuning leeway there then!) ive had the SMF fitted for a couple of years, ive used the car for speed tests, drag starts etc etc, the engine/ SMF clutch still works perfectly/ smoothly

 

Diesels have been around for over 100 years (long before DMFs) they did not need DMFs or much of the other junk stuck onto modern engines (EGRs, CATs, DPFs  etc) that add weight, compexity, reduce performance, economy and reliability

 

If you are modifing a performance car one of the 1st things they do is ditch the DMF and fit an SMF/ solid fluwheel, examples of this are the original Streetperformance Mondeo mk3 2.2 diesel (very quick car) and the 300Hp Mondeo ST220 with throttle bodies, developed by Noble, featured in FastFord magazine, (there was £££££££££s spent on this car, do you think they fitted an SMF to save money, because they could not afford a DMF? not )

 

Ford make an SMF, its a genuine part that can be fitted to a transit, (so it could be fitted under warrantee etc) it comes with a special aux pulley/ crank damper (i thing its more about NVH than component longevity though) - mine seems to be smooth but maybee its my driving styie - perhaps i "drive through" the "bad vibrations" , or the refinement issues on other cars fitted with SMFs are exaggerated?      

artscot79
I think its down to the car if im honest some have no issues some are just awful true they may be imbalanced or improperly fitted causing the negative feedback the taxi is a skoda octavia so fits in that vw dont seem to like them hence vw skoda and seat not responding well to these smfs the references ive made are from the makes above forum that im still on and feedback from those who have had it done there has been a post here before about a smf fitted to a foci and having nothing but problems with it in the end its youre choice mate its youre money as foca said have a garage do it who knows what they are doing
flying clutchman

One thing to mention is that ford originally put a dmf in a lot of the fwd transits but soon changed back to smf, only putting the dmf on the 100psi model. I've heard all the horror stories but then when mondeos came out people claimed windscreens fell out if you undid the subframe. I've done scores of mondeo clutches without this ever happening. I really believe the dmf is a comfort aid rather than a technical issue. It's a great money-spinner for LUK by the way. They probably supply them to ford for manufacture at no extra cost, knowing that when they're knackered they'l be able to charge £££s for the replacement.. Incidently the first dmf I came accross was on a bug-eyed scorpio (petrol) about 20 years ago. It used the same engine and gearbox as the earlier model, but different flywheel and clutch.

artscot79
Like many things now its a con i dread if all cars end up with dual clutch systems bad enough having one replaced never mind two its the same with drls all a con from the big manufacturers
FOCA

Like many things now its a con i dread if all cars end up with dual clutch systems bad enough having one replaced never mind two its the same with drls all a con from the big manufacturers

+1, EGR valves, Cats on deisels and DPFs come under this catagory too, IMO (for example a Mk3 Mondeo on its 4th overpriced EGR valve)

artscot79
I must admit.its the reason i walked away from vw the prices for parts were ridiculous seems like all manufacturers are heading that way except korean brands hyundai and kia are an example
Pitmonster
Fantastic detailed explanation from artscot :-)

FOCA, you've clearly done a *proper* repair, and not a cheap SMF job. Can you say how much your balanced flywheel and special carbon/kevlar clutch cost? (Including garage labour where applicable)

3 months ago Ford charged me £1000 for a new DMF, clutch, slave cylinder, plus labour & vat - with a 12 month warranty on the lot. That will easily last me the lifetime of the car (or at least the rest of my ownership - it has 85k on the clock now, and the new parts will last at least the same again = 170k by which time I will have got rid)

Just curious how the two jobs compare. Thanks
flying clutchman

Fantastic detailed explanation from artscot :-)

FOCA, you've clearly done a *proper* repair, and not a cheap SMF job. Can you say how much your balanced flywheel and special carbon/kevlar clutch cost? (Including garage labour where applicable)

3 months ago Ford charged me £1000 for a new DMF, clutch, slave cylinder, plus labour & vat - with a 12 month warranty on the lot. That will easily last me the lifetime of the car (or at least the rest of my ownership - it has 85k on the clock now, and the new parts will last at least the same again = 170k by which time I will have got rid)

Just curious how the two jobs compare. Thanks

Don't think you can compare the two jobs as the one foca describes is a performance upgrade. You repair was a normal like-for-like job.

jimmygixer

I changed to a  solid flywheel about 6 months ago. To be honest at first i didnt like it at all. You have do be far more precise with your gear changing and working with your clutch biting point as its far more harsh, if you want smooth changes.

But after a while of getting used to it , its 100% now.

It seemed to get better after some miles on the new clutch also, smoothness and noise.

It trains you to be far more precise and kind to your clutch and transmission i found, and you know it wont suddenly decide to shit its self.

Kadan II

Well guy's thanks for all the advice I looked at all the pros and cons and got a good deal from the garage DMF kit £350  6 hours labour to fit all for £645 inclusive of vat great deal I thought car running great now.

thanks to Jason of JRC motors Sandhaven Aberdeenshire great guy

flying clutchman

Well guy's thanks for all the advice I looked at all the pros and cons and got a good deal from the garage DMF kit £350  6 hours labour to fit all for £645 inclusive of vat great deal I thought car running great now.

thanks to Jason of JRC motors Sandhaven Aberdeenshire great guy

yep, that's about as good a deal as you'll find, anyone saying they'll do it cheaper probably don't know what they're doing!

IINexusII

Sorry for bumping this.

 

My DMF is also on its way out, and i've been given a quote for £650 from an independent ford specialist (great guy, been to him many times).

 

the question i had is that is anyone running a bluefin/superchip on their 1.8 tdci? i was thinking of getting the car re-mapped after the new DMF and wanted to know how much it would add to the wear. thanks.

Stoney871
I have bluefin on mine and the clutch is going strong at 85k.
FOCA

Sorry for bumping this.

 

My DMF is also on its way out, and i've been given a quote for £650 from an independent ford specialist (great guy, been to him many times).

 

the question i had is that is anyone running a bluefin/superchip on their 1.8 tdci? i was thinking of getting the car re-mapped after the new DMF and wanted to know how much it would add to the wear. thanks.

Yes, should be ok, most remaps follow the torque curve of the stock map (ie - bluefin), so does not increase the stress on the trans by a large amount  

 

If you significantly increase the torque at low revs (eg remove the restrictions placed on some stock cars in the lower gears - eg 1st/2nd on the Mondeo ST-TDCI 2.2) it can put more stress on the DMF

 

So for cars with serious power/ torque increases its recommended to upgrade the DMF to a stronger one (eg Sachs planetery) or a solid flywheel/ SMF - if you are fitting an SMF i recommend you fit a clutch with a sprung plate - upgrading the clutch is a good idea too (stonger clamping force)

 

My DMF destroyed itself about 95k, the extra low end torque hastened its demise (its the torque at low revs that "kills" it - not the maximum amount of torque (if its gradual or progressive) or power) 

 

The way i think about it is why put a replace component that you know is "soft" the same as the one you took out that wore "prematurely" or only lasts xxK miles? - better to fit a stronger one that will last longer

 

The longevity of the DMF also depends on the way it is driven - and it will wear out quicker if it is driven hard/ used at low revs in a high gear or used for towing etc

 

If you are just remapping it it should be ok but if you plan future power- enhancing mods it may be a good time to upgrade the DMF/ clutch 

 

Other considerations are if you intend to keep the car for a long time (so you fit the best bits you can) or if you intend to change it soon(ish) (just do what is nessesary/ "less expensive")

 

Ive had my solid flywheel/ carbon fiber clutch with sprung plate and heavy- duty backplate + increased clamping force - i prefer the feel to a DMF, the DMF is "sloppy" and seems to introduce play in the transmission - the SMF feels more "precise"/ "direct" gear changes have to be timed right - i prefer this - it suits my driving style

 

Ive heard all the rubbish about the SMF breaking crankshafts etc - im glad i ignored this and listened to the experts - personally, i wouldent have a DMF near my car, especially not a cheap one/ LUK one

 

After 2 years of hard driving/ drag starts with a seriously power tuned motor - still now sign of slipping

 

And the thing about the refinement - an SMF is a whole lot smoother than a DMF on the "fritz"

 

Perhaps cheap, unbalanced, badly fitted or miss- matched solid flywheels were fitted to the cars that seem "agricultural"?                 

IINexusII

Yes, should be ok, most remaps follow the torque curve of the stock map (ie - bluefin), so does not increase the stress on the trans by a large amount  

 

If you significantly increase the torque at low revs (eg remove the restrictions placed on some stock cars in the lower gears - eg 1st/2nd on the Mondeo ST-TDCI 2.2) it can put more stress on the DMF

 

So for cars with serious power/ torque increases its recommended to upgrade the DMF to a stronger one (eg Sachs planetery) or a solid flywheel/ SMF - if you are fitting an SMF i recommend you fit a clutch with a sprung plate - upgrading the clutch is a good idea too (stonger clamping force)

 

My DMF destroyed itself about 95k, the extra low end torque hastened its demise (its the torque at low revs that "kills" it - not the maximum amount of torque (if its gradual or progressive) or power) 

 

The way i think about it is why put a replace component that you know is "soft" the same as the one you took out that wore "prematurely" or only lasts xxK miles? - better to fit a stronger one that will last longer

 

The longevity of the DMF also depends on the way it is driven - and it will wear out quicker if it is driven hard/ used at low revs in a high gear or used for towing etc

 

If you are just remapping it it should be ok but if you plan future power- enhancing mods it may be a good time to upgrade the DMF/ clutch 

 

Other considerations are if you intend to keep the car for a long time (so you fit the best bits you can) or if you intend to change it soon(ish) (just do what is nessesary/ "less expensive")

 

Ive had my solid flywheel/ carbon fiber clutch with sprung plate and heavy- duty backplate + increased clamping force - i prefer the feel to a DMF, the DMF is "sloppy" and seems to introduce play in the transmission - the SMF feels more "precise"/ "direct" gear changes have to be timed right - i prefer this - it suits my driving style

 

Ive heard all the rubbish about the SMF breaking crankshafts etc - im glad i ignored this and listened to the experts - personally, i wouldent have a DMF near my car, especially not a cheap one/ LUK one

 

After 2 years of hard driving/ drag starts with a seriously power tuned motor - still now sign of slipping

 

And the thing about the refinement - an SMF is a whole lot smoother than a DMF on the "fritz"

 

Perhaps cheap, unbalanced, badly fitted or miss- matched solid flywheels were fitted to the cars that seem "agricultural"?               

i plan on keeping it for the long run, as long as i dont get any other problems which will probaly get me too angry and sell it off.

 

this Sachs planetary you talk of, is this the same one as the one in eurocarparts?

 

also the garage i am going to gets 50% off genine ford parts due to having a trade account with them, he will be using genuine ford (LUK) parts.

 

i'm at 116k at the moment, so im probably running on overtime :S car drives fine though, apart from it feeling vibrating which is probably the DMF but i dont want to risk it blowing as i need the car everyday for commuting

FOCA

The stock LUK one could last another 100k+ (is that your 1st one at 116k/ have you had the car from new?) even with the remap - so it could be several years before if becomes a problem again (to put it in perspective) but the Sachs planetery one is stronger/ better, in my opinion - discuss it with your independant Ford specialist - see what he says about the Sachs

IINexusII

i bought the car from 100k (for £2400), and no clutch/dmf replacement as far as i know from the service history... the car had slight rattling if i dump the clutch when stationary when i bought it so i suspect the owner knew about it and wanted to get rid! its been mostly motorway driven, and with my driving style i don't think ill make a new one last that much :P

 

ill be talking to the garage and i've also emailed Sachs to give me the part number for the planetary dmf. if it is the one on carparts4less, then it will be £199.99.

 

http://webcat.zf.com/index.asp?PKW=1&KHERNR=36&KTYPNR=18935&KMODNR=5210&KAT_KZ=P&ARTNR=2294+000+660&EINSPNR_ART=32&LASTPAGE=nc2_teile_info.asp

 

http://www.carparts4less.co.uk/cp4l/c/Ford_Focus_1.8_2005/p/car-parts/car-transmission/clutch-and-associated-parts/flywheel/?336590570&1&41adb2f9ac903bd3c2e2df36a56aaef8d13a4601&000134

 

edit: well that was a quick reply...

 

Hello Mr xxxxx


The
part number 2294 000 660 is a planetary DMF and is the correct one for
your vehicle. If you are replacing the DMF then we would recommend that
you also replace the clutch kit. 2290 601 013 is a complete
module kit that contains the clutch, fly wheel and concentric slave
cylinder.


I have attached some service information about the Sachs Planetary DMF.
It explains the function of the unit and some checks that should be
carried out on the vehicle to prevent premature failure of the DMF.

 

I've added the documents for anyone needing the info

 

if this is the case then i could just go to my local garage in london rather than the ford guy in cheltenham where i work and get them to replace it, while i oversee the operation. that would come to around £450-500 with the sachs clutch kit



This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.
Invision Power Board © 2001-2014 Invision Power Services, Inc.