Technical Clutch Chatter mystery

[Lukeb9433]

A few years back I restored a '59 500. Ever since I took it for a first drive it has had a horrendous clutch chatter - the car bucks hard enough to knock you teeth out!.
I replaced the clutch, which helped a little.. (it was undrivable previously)- I then tried replacing the pressure plate, which made no difference.
I have also replaced all of the engine mounts during the restoration.

I am able to get the car moving only by letting the clutch out very quickly with with my foot almost off the gas pedal..
The is absolutely no problem in reverse or if I start off in second gear.

Has anyone had this issue or know what could be causing it?

Thanks, Luke

 

[oopsadaisy]

Hello and welcome to the forum.

So, just to clarify, you can slip the clutch OK in second gear and reverse, and this only happens in first gear?

 

[Lukeb9433]

That's correct.. I'm beginning to think it may have something to do with the main engine mount with the spring. I know the engine torques the opposite direction in reverse...

Luke

 

[oopsadaisy]

I don't think so Luke..... if it doesn't happen when you take off in second gear it is all pointing to a gearbox problem.

 

[Lukeb9433]

The weird thing is that once the car is moving, there is no vibration.. That's why I initially thought it must be the clutch. I had the car out today - I tried watching underneath while someone else slipped the clutch. The whole drivetrain hops up and down, pivoting around the axles. I wonder if the top of the transaxle us smacking against the floor pan.... That doesn't explain what starts the oscillation, though..

 

[Bambino]

Bizarre - any chance of a video ??

Chris

 

[oopsadaisy]

That doesn't explain what starts the oscillation, though..

No, it doesn't - and that's the worrying bit.

Have the internals of the gearbox ever been looked at?

 

[Lukeb9433]

Yes - I had the gearbox apart. Everything looked pretty good... I can't think of any gearbox issue that could cause a problem like this.

 

[oopsadaisy]

Well, we have a real mystery here.

So, just to recap and be absoulutely clear:

• When you slip the clutch in first gear, the engine jumps around on it's mountings.
• It doesn't happen if you try to take off in second gear.
• It doesn't happen in reverse.

All correct?

Probably a really silly question, but have you tried taking off in third or fourth gear?

If so, what happens?

 

[Bambino]

It's got me foxed.

Most clutch judder will occur when the lowest gears are engaged eg: 1st and reverse, and is usually due to clutch plate misalignment, flywheel distortion, broken engagement springs, oil on the clutch plate or very rarely, a loose pressure plate.

Can't say much more without looking at it in action as it may be something else entirely.

Chris

 

[bzxhms]

Hi there, I recently replaced my clutch cable on my 59 500 and had same problem. Check that you have used the right stud on the gearbox to afix the clutch cable.
I used the stud closest to the front of the car not the rear. When i first installed I mounted it on the rear stud and had same problem you are describing. Changed mounting to front stud and all good know. Hope this all makes sense and helps you fix your problem. If you need pic let me know.

 

[Lukeb9433]

That's very interesting... I had a look underneath again, and I noticed the bracket on the clutchcabe conduit isn't attached to anything! I would love to see a picture-

 

[bzxhms]

Here's the picture, hope this helps.

 

[Lukeb9433]

I ordered a new engine spring to see if that would make any difference - the new spring was about an inch taller than the old one and much stiffer. I guess the old one had sagged.. Not much noticiable diffence.

I have to say I was at first skeptical about your cable idea - But like I said, I found that my bracket wasn't attached to anything. I loosened the cable and moved the conduit up so the bracket would reach the stud. And PROBLEM SOLVED!!! I never thought such a violent chatter could be caused by such a simple thing..

Many many thanks!!! :worship:

Luke

 

[oopsadaisy]

Amazing!

Well, I've certainly learned something today!

Big thanks to bzxhms for coming up with this fix!

 

[dk500]

Hi
I have that judder as described.
I have to come off clutch just right with virtually no gas to ensure there is no judder.
I have attached photos similar to previously posted, however I have no idea which cable is which ?
Any pearls of wisdom ?
Thanks
Darryl

 

[Vitesse]

Darryl it looks a bit odd. It looks like, but I can't see clearly that the clutch cable has been bolted to the chassis that supports the swinging arm. It looks like there are two clamps? The clutch cable should be on the clamp that is at the back of your 2nd picture bolted to the side of the gearbox but I can't see in that picture whether there is a cable on that clamp?

Tony

 

[Vitesse]

Having looked at it further and looked at my other gearbox it looks like the clutch cable clamp has been bolted on to the bolt in front on the gearbox. The one above where the gearbox rubber mount is.

 

[dk500]

Hi tony,
There is a cable in both clamps.
I thought they both seemed to be attached to the gear box, but I will have another look and maybe a better photo tomorrow.
Are you referring to the blue nut as the clamp that should have clutch cable ?
How would I confirm which is clutch cable ?
Thanks
Darryl

 

[dk500]

Having looked at it further and looked at my other gearbox it looks like the clutch cable clamp has been bolted on to the bolt in front on the gearbox. The one above where the gearbox rubber mount is.

Am I correct in thinking that is how it should be according to this thread.
Sorry, where is the gearbox rubber mount ?