The clutch on my TD4 has given up, so I'm expecting to replace the DMF at the same time. Whats the current thinking/advice on replacing the DMF with a solid flywheel ? Plenty of kits about all promising good things, but has anyone done it and have now covered a good few miles ? I have had a search on here and google, lots of conflicting views but all seem to be from a few years ago. Be nice to know what the latest thinking/experience is.

Even LR fitted a solid flywheel to the Transit's Puma engine when it went into the Defender.
I'd fit a SMF without question. My TD4 isn't that rough running and it doesn't have a DMF. It has 20Kgs of solid mass torque converter instead.

Thanks, fitting an SMF does seem to make sense but I was really hoping someone who has fitted one and run the car like that for a while would chip in - but maybe no one has !

Only real world advice I can give.
My work van, that someone nicked the other week, had a DMF, but when it was replaced it had a SMF put in. The main difference I noticed was that it kicked more when under load and changing gear. The DMF is definitely smoother, but the SMF should last considerably longer.
Mike

Whistler said:

Thanks, fitting an SMF does seem to make sense but I was really hoping someone who has fitted one and run the car like that for a while would chip in - but maybe no one has !

Click to expand...

A few have fitted the SMF to a Freelander. From memory, they didn't really notice it. Do a search on here. I think SES88 fitted one on his FL1.

Dual. Look towards the 75 forums and the problems boys have with snapped cranks when they have single mass.

Cranks in our engines are cast not forged and do give problems with snapping more and more.

Infact several of the tuners won't touch a 75 with solid mass flywheel conversion, so surely a td4 with the drive train putting it under pressure before you up the power can only make things worse.

It acts as a torsional vibration damper, in much the same way as the diesel crankshaft front pulley.

http://forums.mg-rover.org/mg-zt-ro...ching-475080/#/topics/475080?page=1&_k=xke802

MacGyver said:

Dual. Look towards the 75 forums and the problems boys have with snapped cranks when they have single mass.

Cranks in our engines are cast not forged and do give problems with snapping more and more.

Infact several of the tuners won't touch a 75 with solid mass flywheel conversion, so surely a td4 with the drive train putting it under pressure before you up the power can only make things worse.

It acts as a torsional vibration damper, in much the same way as the diesel crankshaft front pulley.

http://forums.mg-rover.org/mg-zt-ro...ching-475080/#/topics/475080?page=1&_k=xke802

Click to expand...

Cast cranks snapping isn't related to the DMF. Pretty much all standard engines right up to the early 90s had cast iron cranks. Many engines still do, like the M47R. Those old engines didn't have DMFs and many didn't have dampers on the crank nose. Very few cranks snapped in use. If the M47R crank is snapping more than it should? It's probably down to a manufacturing error. Cast iron cranks break due to stress raiser imperfections. So it'll be caused by a bad drilling of an oil way. Or a journal radius that was badly formed when ground.
This is pretty important stuff that needs to be correct. If the cranks are badly made, a DMF isn't going to save them from breakage.

I can't believe BMW would make a crank that was inherently weak in design. But again, a damper or DMF isn't going to save a weak crank design.

If that were the case, auto TD4s would fail just as often. They don't have MDFs but have a 30Kg lump of torque converter stuck on the end of the crank.

The damper is there to reduce torsional vibration from the crank. The DMF is there to remove power stroke vibration from the gearbox and drive train.

The crank in our car and the 75 is not forged.

The crank in the M47tud20 (common rail e46 onwards) is forged

The m47r shares the same block as the previous generation m47d20 which didn't have a forged crank either.

Rover / Steyr did all the development work and then bmw let them make the mistakes and make the engine stronger even if things like swirl flaps became the common issue on them.

Not the m47r and the M47tud20 are similar at a glance but built vastly different to a different level of component quality. They even expanded the cc also just to claim the block wasn't the same sure as the rover lump when rover become a bad word for bmw.

Just don't if you do like driving. I used to use my old freelander for offroading and driving to work. Working at Euro Car parts meant that I got a cheap deal on a good valeo SMF kit.
But it made driving hell. Would judder like mad! Even more so in slow moving traffic.

So much so I sold up and bought the disco.

I would put a DMF for what its worth.