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Dual mass flywheel

Synchromesh wrote:Dual mass flywheel

Agreed for the kangarooing symptoms, suspect the other issue may be something else.

If it's about to be replaced, just don't drive the thing. Hiring a car for a week is probably cheaper than investigating/fixing any problems.

What is supposed to be good about the DMF? Never quite understood the purpose of them...

Not driving it is actually quite easy for us to do, it only did about 5000 miles between its annual services last year, and the tyres on it have been on for the last 3 years now and still have a load of tread on. We have 2 cars in the house, and the Galaxy is only really used for days out, the Yeti is used for just about everything else.

TheInsanity1234 wrote:What is supposed to be good about the DMF?

Modern turbo-diesel engines have relatively huge spikes of power at low engine speeds; the DMF is designed to prevent damage to the drive-train from the engine. I understand the main causes of failure are not depressing the clutch when starting or stopping the engine, and putting the engine under load at low engine speeds. For the latter, it the engine sets up a vibration through the car, then the engine speed is probably too low and the DMF is unable to absorb the vibration.

Gareth wrote:

TheInsanity1234 wrote:What is supposed to be good about the DMF?

Modern turbo-diesel engines have relatively huge spikes of power at low engine speeds; the DMF is designed to prevent damage to the drive-train from the engine. I understand the main causes of failure are not depressing the clutch when starting or stopping the engine, and putting the engine under load at low engine speeds. For the latter, it the engine sets up a vibration through the car, then the engine speed is probably too low and the DMF is unable to absorb the vibration.

Well, that explains why the Yeti won't start the engine unless you've depressed the clutch. Always assumed it was some kind of protection against damaging the starter due to trying to start the engine whilst a gear is engaged.

Although I find the fact the gear-suggesting-thing-which-I-ignore does seem to encourage you to drive in the highest gear possible, which sets a nasty vibration going through the car unless you're travelling at a speed which means the rpm is above 1500.

TheInsanity1234 wrote:Well, that explains why the Yeti won't start the engine unless you've depressed the clutch

No, it's just a very common interlock to stop you starting the car in gear.

Mr Cholmondeley-Warner wrote:

TheInsanity1234 wrote:Well, that explains why the Yeti won't start the engine unless you've depressed the clutch

No, it's just a very common interlock to stop you starting the car in gear.

... which could be exceedingly useful in some circumstances.

Gareth wrote:

Mr Cholmondeley-Warner wrote:

TheInsanity1234 wrote:Well, that explains why the Yeti won't start the engine unless you've depressed the clutch

No, it's just a very common interlock to stop you starting the car in gear.

... which could be exceedingly useful in some circumstances.

The only circumstances I can think of involve a very weak handbrake and a steep hill...?

Broken clutch is one, Insanity. In those circumstances, when you need to stop, you have to get going again somehow. I know at least one person who's completed a journey of several hundred miles this way

Mr Cholmondeley-Warner wrote:Broken clutch is one, Insanity. In those circumstances, when you need to stop, you have to get going again somehow. I know at least one person who's completed a journey of several hundred miles this way

What, as in the clutch pedal broke, so the clutch was always engaged?