1.6hdi clutch flywheel or solid ??

[jsp]

Valeo kit4p is the best. Been fitted a lot of times here in my workshop and drives like dmf.

[citroenc5mad]

Still driving great no problems to report at all.
Was skeptical at first but you couldn't tell the difference.
I would say get one but others would say keep it stock.
Sorry about late reply haven't been on for a while.

[jsp]

See I told you feels almost no difference.

[Bob L'eponge]

Valeo kit4p is the best. Been fitted a lot of times here in my workshop and drives like dmf.

When I changed the clutch on my C5 I looked at this kit, and it was about 160 Euros cheaper than I could get a complete replacement Sachs clutch and DMF kit. However, I went for the OE option as the 4p kit just moves the damping from the flywheel to the clutch plate, using longer springs, and I did wonder how those springs would stand up long-term to all the work they were doing. OK, if they do fail only the plate and cover needs to be replaced, but compared to the hassle of stripping off the box, another 160 Euros is neither here nor there.

Do you have any information as to how long the 4p plate damping springs work effectively before the plate needs to be changed?

It is also worth noting that even Valeo themselves say that for high-torque engines a DMF is necessary as the damping offered by their long-spring clutch plate is insufficient.

As I said earlier, I think that the biggest issue is people overheating their clutches, as this damages the rubber dampers fitted to a DMF. Treat the clutch with respect and don't overheat it and a DMF should (should...) have a long service life. (My wife's car is fitted with a Renault 1.5 Dci engine with DMF and still drives perfectly on the original clutch, which now has 240,000 km on it.)

[jsp]

1.6/2.0 hdi Berlingo didnt have the DMF and heavier than all the cars full loaded and had factory KIT4P. So why do you need a DMF just for the comfort over reliability? It works all the same springs are in the plate or flywheel all the same. As long as the total weight of the kit is the same I chose SMF. I have put on kit4p on weight scale and dont differ a lot on the weight so the feel is minimum.

Diesel engines arent that glass weak compared to Petrol engines. They can stand against a lot of tq in comparison with petrol engines. Loads of them on high tq are converted to SMF as the DMF wont hold thold it very well on long term. Comfort or reliability its up to you to choose.

2.0 HDI on KIT4P lasts longer than 260.000km been tested in a 407sw HDI with near 620.000km. Replaced at 260.000km still in the car this kit.

[aneesh84]

1.6/2.0 hdi Berlingo didnt have the DMF and heavier than all the cars full loaded and had factory KIT4P. So why do you need a DMF just for the comfort over reliability? It works all the same springs are in the plate or flywheel all the same. As long as the total weight of the kit is the same I chose SMF. I have put on kit4p on weight scale and dont differ a lot on the weight so the feel is minimum.

Diesel engines arent that glass weak compared to Petrol engines. They can stand against a lot of tq in comparison with petrol engines. Loads of them on high tq are converted to SMF as the DMF wont hold thold it very well on long term. Comfort or reliability its up to you to choose.

2.0 HDI on KIT4P lasts longer than 260.000km been tested in a 407sw HDI with near 620.000km. Replaced at 260.000km still in the car this kit.

Do your mean that the KIT4P clutch lasts this long! This seems longer than the usual life for a standard SMF clutch. Another issue is when the KIT4P clutch does go, I am told that a replacement clutch costs almost the same as the whole kit. Can you please confirm?

[Bob L'eponge]

Diesel engines arent that glass weak compared to Petrol engines. They can stand against a lot of tq in comparison with petrol engines...

But aren't DMF's primarily intended to reduce the peak torque loadings on the transmission? Hence a DMF allows a lighter transmission to be fitted without fear of it failing.

[jsp]

DMF is just comfort driving at low speeds.

Why some 1.6/2.0 HDI engines have some dont. Depends on comfort or reliability. ML transmissions are overbuilt is specially meant for HDI hence it can handle this kind of tq.

[Bob L'eponge]

More on DMF's:

"SACHS dual-mass flywheels are installed as standard features in many vehicles and have the following advantages:

Isolated engine vibrations
Reduced noise
Prevent transmission damage
Improved shifting comfort
Quieter start-up behavior"




https://www.zf.com/brands/en_de/sachs/p ... eel_1.html

Also:

http://www.schaeffler.com/remotemedien/ ... heel_1.pdf

[jsp]

Please look at the KIT4P video first before you post something that is not even correct.



Valeo kit4P is different than what you stated on the pictures as the springs are much larger and are double springed see pictures so it vibrates as same as the DMF than a std. clutch set to compensate vibration. The clutch plate in the Kit4P has the springs what is inside the DMF so it compensates vibration. It drives the same almost to no difference.





I am not endorsing stuff or anything I am just making my point of an useless feature which is not needed.

[Paul-R]

I am aware that on the solid flywheel conversion kits that the friction plate has larger springs, and probably other things, to replace the effect of the dual mass flywheel. The manufacturers claim that it is as effective as the dual mass flywheel otherwise they wouldn't sell them. But if that's the case why are the DMFs produced at all?

[jsp]

Probably because the effort to make Diesel cars drive like petrol and afterwards thinking ooh we should make SMF aswell as DMF breaks down a lot. Dealers dont sell this option to let you pay more and more.

[Bob L'eponge]

Please look at the KIT4P video first before you post something that is not even correct. .

The details I posted come straight from the technical data sheets of the manufacturers.

Also, I did say "the 4p kit moves the damping from the flywheel to the clutch plate, using longer springs".

Main point is those extra-length springs in the 4p kit will still be doing a lot of work damping the peak torque values, and would seem to be just as likely to develop play as the springs in a DMF, so overall one might well still end up having to service the clutch unit more frequently. I'm not saying that the 4p kit isn't a good alternative but the peak torque values of a modern diesel, and the added damping requirement, will always increase service costs.

[white exec]

IIRC, DMFs have fairly massive possible sprung movement between the two 'halves' of the flywheel, compared to the much lesser rotational movement of a traditional (or newer SMF 4p) friction plate.

The very long DMF springs, which can allow more than 45deg of 'sprung rotation' become compressed over time, and the sprung cushioning they provide becomes sloppy and with backlash. There are also friction components incorporated into the DMF, to damp unwanted long-spring oscillations. These also wear, and the result can be rotational backlash without damping - not a happy outcome.

The result of this 'sloppy' flywheel is poor clutch control, difficult hill starts, and greatly increased wear on the accompanying unsprung friction plate, which can be literally chewed up by the snatchy flywheel face. This sort of premature damage is routinely seen by those who have had to replace DMFs.

DMF is a means of reducing engine vibration somewhat, but at a cost. It has probably allowed engine and transmission manufacturers to use lighter weight components, and to offer engines with increased harshness, masked by a bit of driveline springing.

Just one more reason to look beyond the internal combustion engine. Electric drive, bring it on.

[Bob L'eponge]

DMF... has probably allowed engine and transmission manufacturers to use lighter weight components, and to offer engines with increased harshness...

It's not so much that the manufacturers look to sell engines that are 'harsher', rather DMF's have been a response to the increased peak torque values that a modern common-rail diesel engine can produce. (Which I suppose could be seen to be the same thing, although most would see a 'harsh' engine as being a negative thing, but increased torque as being a positive.)

This what Valeo (who make the 4p kit) say about their DMFs:

Today’s modern engines produce higher torques that can be driven at low engine speeds. As a result, the maximum engine torque to be transmitted increases thus resulting in an increase of noise and vibration.

Moving the damper springs from the conventional clutch plate to inside the flywheel allows the D.M.F to filter the torsional engine vibrations away from the gearbox and reduces the load on the transmission line. The larger damper in the D.M.F is better suited for filtering the engine vibrations (especially needed for turbo diesel engines). Gear shifting comfort is also improved with a low-inertia disc.

The D.M.F. allows driving at lower engine speeds increasing engine efficiency, thereby saving fuel and reducing CO2 emissions as well as any vibration that can cause “gear rattling” & “body booms”.

http://www.eai.net.au/Transmission%20Sy ... screen.pdf

I don't think that DMF's are flawed in concept, and in my experience can run fine for high mileages (the one on my wife's car has done 240,000 km, and the one in my Fiat was fine at 120,000 miles when the clutch release bearing went) but they probably do need treating with respect.