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The Boss

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hey folks..

thinking out loud here..

back to my previous thread about the slight rattly noise from under the car, I was talking to my MOT guy today and he suggested the rattle could be from the torque convertor..

some one on here suggested it might be tappet buckets or something like that, but he disagrees.

anyone have experience on the torque convertor and can some one tell me what it does, and how it may cause a rattle on acceleration.

reminder.. the rattle noise comes only when in gear, or reverse, but is not noticable at all when in park or neutral.

thanks
 
The torque convertor is a fluid coupling that transmits power from the flywheel to the gearbox. it takes the place of the clutch in a manual gearbox.

The vanes in the stator can become loose and possibly cause a noise.
 
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The torque convertor is a fluid coupling that transmits power from the flywheel to the gearbox. it takes the place of the clutch in a manual gearbox.

The vanes in the stator can become loose and possibly cause a noise.

Just to describe the symptoms here.

1. no noise when car is switched on, and in park or neutral.
2. as soon as drive, or reverse is selected, the noise begins.
3. the noise continues when accelerating.
4. the gear change is smooth and perfect.
5. there is no stalling and the drive is perfect, only the noise is an irritation.

The noise seems to come from an area just in front of the torque convertor, just above the sump shield.

there is no rattly heat shield as was once thought, all looks perfect!
 
Could it be a rattling catalic converter?

could be, but would this noise be in the area of the torque convertor.

its noticable upfront, not at the rear.

The area is literally under the car at the bottom of the gearbox, in the same line as right under the position of the wiper, but right at the very very bottom
 
could be, but would this noise be in the area of the torque convertor.

its noticable upfront, not at the rear.

The area is literally under the car at the bottom of the gearbox, in the same line as right under the position of the wiper, but right at the very very bottom

Which model of w124 do you have?
 
cabrio 320ce 5 speed auto

The cat or cats on your car are further back, more level with the front seat base's. Get underneath the car and give them a whack with the palm of your hand, you should be able to hear if they are rattling. :thumb:
 
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2 pence:

Rattling/funny sounds comming from underside:

4 post ramp > get the mechanic to lift the car with you in it > once up switch the car on > put in D > get your mechanic underside to hear where noise is comming from.
 
BillyW124 said:
2 pence:

Rattling/funny sounds comming from underside:

4 post ramp > get the mechanic to lift the car with you in it > once up switch the car on > put in D > get your mechanic underside to hear where noise is comming from.

Done already. Sound is in between torque convertor and rear of engine
 
The flex plate - which is the plate which connects the engine's crankshaft to the torque convertor - may be cracked.

As torque convertors are fabricated parts, they don't have a tight alignment tolerance, and so, they need a flexible mounting plate to allow a bit of "wobble". Each time the crank turns, the plate flexes a bit, and at high mileage, the plates crack.

Typically, the cracks grow from either the crank bolts at the centre of the flex plat outwards, or, from the torque convertor bols on the rim of the flex plate inwards.

If it's the latter case, you may be able to see the damage by removing the plastic cover, and then turning the crank by hand while watching the torque convertor and flex plate.

The other thing you might be able to do is to prod the torque convertor with a stout screwdrive through this bung, and see if it moves a bit, and makes any noise.
 
Thanks Number Cruncher. I had always wondered why it's called a flex plate.

Cheers

Adam
 
It's a good job someone didn't buy this car for the, what was it...£500,000 you thought it was worth, and then have all these problems, it could have got you bad rep...


Lucky...


Good luck with the fix.
 
ya, its having a few probs at the moment. some one said i should just use it more, it will get fixed soon enough.. gonna book it in with the main dealer at some point to give it a once over
 
Just dont put it back up for sale at £35,000 when this problem is solved lol. Nah just kidding mate, its a beautiful car and I hope you get that problem fixed. I know how annoying little rattles can be when your driving, ends up getting the better of you.
 
Just dont put it back up for sale at £35,000 when this problem is solved lol. Nah just kidding mate, its a beautiful car and I hope you get that problem fixed. I know how annoying little rattles can be when your driving, ends up getting the better of you.

ofcourse.. more like £40k.. but its not gonna be for sale for a while..

i just wake up and go down to the garage and get a smile looking at her.

did a 15 mile drive in her the other day, and it put such a big smile on my face.. seriously overwhelmed with how comfortable she is,

these issues will just mean i need to give her one major check over, and then probably increase the heating in the garage.. dunno..

there is one tiny squeak from the interior kick panel on the passenger side, i just need to look at that, but the interior really feels so cozy.. my plan is to give her a nice 500+ mile road trip some time .. should be a fun weekend of rolling country hills and scenery.. when and where i dunno yet - possibly next summer..

may get her next 30,000 mile service done a little earlier maybe around xmas or so.. lets see.
 
has anyone else noticed the tags on this thread?:eek:
 

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