Dual mass flywheel in a VX auto

[blacknight]

I 've searched in the previous posts and so far i've been coming up with auto to manual conversions that involve issues with the flywheel. Apparently, the dual mass flywheel in my VX has a 'rubber dampener' and when the car starts up there is a loud 'clack' before the engine comes to life. under 1000rpm (750-800rpm) its is defening and rattles very loudly, but once you step on the gas pedal the sound goes completly away. A quick check at the agent showed up a 4 inch crack across this 'rubber dampener' in the DMF for the engine. I can see specks of broken off rubber under the car this morning.

Does machining a DMF a big no? even if it was precisely re-balanced on a lathe? Someone proposed substituting the rubber bit with a similar weighted disc. Would this work?

I have been getting a lot of opinions on this method.

The agent quoted $795 for a brand new DMF that will take about a month to arrive through official channels. I've yet to check ebay or other online sites.

Can someone advise me? What are the benefits of machining a DMF, if any? Its a temporary measure till it arrives

[NSTG8R]

you sure it's not the harmonic balancer on the front of the motor that's stuffed? the sounds you've described sound like the sounds made by a dead harmonic balancer

[scvs6]

If it is the DMF causing the problem, maybe try converting it to the Solid flywheel type. Thats what we usually do with Commodores when they need a clutch, plus it will be cheaper when you go to replace the clutch next time.

[madsav]

That what i did in the VT ss 6speed, Solid flywheel took awhile to get use to but now its jump grab and go so more sail race
Like scvs6 said its ALOT cheaper when the clutch needs to be replaced <---(LIKE)

[acarmody]

Wait I'm confused, OP do you have an auto or a manual??

[VTS5]

Dont really know what you talking about,but here is the deal,NO you cant machine the flywheel,NO there is no rubber dampener built into it.NO you cant balance it.Unfortunately there is nothing else you or anybody else can do other then replacing it with the solid or DMF.

""even if it was precisely re-balanced on a lathe?""

This is funny :-) Did you know,A special balancing procedure is followed at manufacture that involves rotating the wheel to 6000 rpm.for a minimum amount of time prior to undertaking balancing at normal speed??

"I can see specks of broken off rubber under the car this morning."

What??

[blacknight]

Its an auto transmission. My VX has a huge 4 inch crack across the dual mass flywheel right across the rubber dampener. Its not one of the pulleys. I took it off yesterday and found bits of rubber (like shredded) in the engine bay.

[scvs6]

Wait, what? Where did you get dual mass flywheel from then? Autos don't have a flywheel like the manuals, they have a drive plate. And anyway, they are not in the engine bay, they are bolted to the back of the engine (bolted to the crankshaft).

Maybe you should take photos of what your talking about because you're confusing people now, or it it just me?

[Cameron P]

Sorry vts5 but you can machine a DMF... I got mine done about 2 years ago with no issues to this day.. And it cost me 700 for machining, clutch and labour. Heaps cheaper then replacing the flywheel.

And Mr op check for cracks in the rubber on the crank pulley.

[Clutchy]

Take ya car to a different agent as ya call him as his taking you Gor a ride sorry to tell you as 1 your car dont have a flywheel it has a flex plate 2 it would not take 4 weeks to get a new. Flywheel not that you need one .

I would check the belt on the front of the engine if thats fine it has to be the balancer hanging off the front of the engine down the bottom as I can't think of anything else that could shred rubber loke you have said ya found.

[VTS5]

Sorry vts5 but you can machine a DMF... I got mine done about 2 years ago with no issues to this day...

In that case,good luck driving a massaging chair.The primary and secondary masses can normally be rotated slightly by hand relative to each other with the result that the dual mass flywheel cannot be clamped securely in order to machine the flywheel face on the secondary mass without damaging the bearing mounted between the two masses, while the two masses cannot be separated without permanent damage to the flywheel assembly.

Machining the flywheel face reduces the secondary mass which adversely affects the torsional vibration damping function of the dual mass flywheel, resulting in increased driveline vibration in the vehicle.

A number of cases where clutch rebuilders and machine shops have tried to recondition dual mass flywheels without success, resulting in severe driveline vibration, clutch shudder and slipping problems

So,i reckon,your DMF is just sanded down lightly or not at all.The kit cost me $975 and took me hour and a half to fitted.

[Cameron P]

My clutch has never slipped or shuddered and nor do I get driveline vibration... And I know this because I drove another manual Vx with a new DMF and it feels the same.

And this is 2 years after it was done... Go figure

[pjdm1980]

WTF is this OP on! BA ha ha ha ha ha.
You need to find a mechanic that is trying to rip you off by the sounds of it.

[acarmody]

It sounds like the OP has a broken harmonic balancer, where the rubber has splits, and is starting to split from the metal.

OP can you show us a photo?

[blacknight]

OMG! Sorry guy! I f**ked up big time. It was not the Dual mass flywheel. It was the harmonic balancer. My regular mechanic took one look at it and said I shouldnt have broken bits of rubber, and the only place where there's rubber is the HARMONIC balancer.

Sorry for the confusion. With the new information, I did a search and found out that these components are designed to fail after 200Ks but my old VX was already running 205Ks + so I guess it gave out when its due. I'm trying to source out a spare as the rattling was getting unbearable, it sounds like a diesel car.

[pjdm1980]

Lol at least you've learnt something! Not a big job for a mechanic and should take him less than a hour.

[VTS5]

My clutch has never slipped or shuddered and nor do I get driveline vibration... And I know this because I drove another manual Vx with a new DMF and it feels the same.

And this is 2 years after it was done... Go figure

I believe you,(unless you are kidding yourself)and i also believe your F/W never been machined and you've been ripped off.Just think for a minute,if there is a slight possibility that those disks can be machined,do you think that we all silly buggers loaded with $$$ spend it big on new ones??Standart clutch kit is only $280.Bulk of the money goes towards the bloody f/w.