Technical Punto Mk2 Diesel Dual Mass Flywheel

[Colin Harrison]

On my '03 Mk2 Punto JTD, I have had a new dual mass flywheel and clutch kit fitted and now a month or so later I have developed a knocking noise. It happens when I start the car, whether the clutch is in or out, and it also happens when pulling away - just a single knock or clonk. If I drive along and then pull my foot off the throttle quickly, I get a knock. It seems to be linked to the torque the engine is delivering, when I pull away on a very pot holed surface near my house, I can get a very load knock. Anyone else had this experience? The flywheel and clutch were fitted by a competent local garage. Could be an engine mount too I guess....thanks for any advice.

 

[Ziggy122]

Check the engine mounts - im going to assume that the Underside dogbone is probably swinging here, or not tight enough

But dont forget about the Gearbox and engine mount - ensure the bolts are all there and torqued up nicely

Ziggy

 

[stealthtuning]

Is it a very loud clonk that you can feel through the floor, or a general knocking noise?
I realise you can never get a real idea of a noise in words!!!

 

[Colin Harrison]

on occasions it is a very load clonk you can feel through the floor. I will check the engine mounts.
What is the dogbone? Is that an engine mount? I assume I need to take out the battery and battery tray to see the engine mounts...

 

[Colin Harrison]

What and where is the dog bone? The engine/gearbox mounting below the battery box is now tightened up - it was not loose but not very tight either. Test drive after that but it is still knocking and clonking...

 

[Ziggy122]

What and where is the dog bone? The engine/gearbox mounting below the battery box is now tightened up - it was not loose but not very tight either. Test drive after that but it is still knocking and clonking...

There is 3 mounts to hold the punto's engines and gearbox in place

The Left hand Mount (driver side) Sits on the wing ish
The Right hand side, sits under the battery tray on most versions
Then there is a 3rd, under the car, inline almost with the firewall, this is also attached to the subframe so the engine doesn't rock itself to death as you demand torque!

ziggy

 

[Colin Harrison]

Got it - thanks. All mounts are tight. I have removed the plastic cover on top of the engine and tried to rock the engine forwards and backwards - when I pull the engine forwards (top of the engine towards the front of the car) I can make the knocking noise! It sounds like it's coming from the dogbone area although I don't really know where the movement is. It's not the top engine mount or the gearbox one. The dogbone LOOKS okay, the rubber is good and everything is tight. I'll try and remove the bolt holding the dogbone to the engine and see if the noise goes away. Any other ideas?

 

[Ziggy122]

Got it - thanks. All mounts are tight. I have removed the plastic cover on top of the engine and tried to rock the engine forwards and backwards - when I pull the engine forwards (top of the engine towards the front of the car) I can make the knocking noise! It sounds like it's coming from the dogbone area although I don't really know where the movement is. It's not the top engine mount or the gearbox one. The dogbone LOOKS okay, the rubber is good and everything is tight. I'll try and remove the bolt holding the dogbone to the engine and see if the noise goes away. Any other ideas?

You've located the noise to the rotation of the engine in itsmounts

It could be the dog bone - a possible suspect
However it could be another component donging as well on the firewall or the subframe etc

You could do with getting the car up in the air and getting under and have a rocking session and prybar attack and see what brings it out in a banging session

Ziggy

 

[stealthtuning]

Ziggy is right. You need to get under it with a pry bar. My money is also on the dogbone, (although I've never heard it called that before!!).
Looks almost like a tennis racquet with a rubber in it. It can look ok, but they can develop a lot of movement. Very common fault! One trick is to wedge a piece of exhaust rubber in it!!!

 

[Colin Harrison]

You win the bet! It is definitely the dog bone. I put a spanner on the nut holding the dogbone bracket to the engine and I can move the whole engine and watch the tennis racket end of the dogbone sliding back and forth under its bolt. The bolt is extremely tight and I'm frightened to break it off!! Any tips? I've got a long torque wrench on it and it's solid.....

 

[stealthtuning]

.... Erm....
If it was me I'd just get the socket over it, maybe hit it with a hammer a few times, then just get as much leverage as I can on it, then just start off gently and gradually increase the pressure on it until I'm at maximum effort!!!
1 of 2 things will happen, it'll undo, or it'll break!
If it breaks it'll need to be either drilled out, or if you're lucky you'll be able to get stilsons on the remainder of the bolt.
Or failing all of that, if you have access to an air gun! Use that!! May be worth getting a quote from a garage, not usually a lot of money, especially if you supply the part, then if it breaks its down to them to sort it!!! ?

 

[Colin Harrison]

Yep, it's off to the local garage...there are plenty of the mountings on e-bay but not for the diesel (typical) - are they the same in the 1.2 petrol Thanks everybody for your help.