Clutch Judder Moving Off...

[jeff_hooper]

Recently, I have become away of a definate 'judder' when I start off from stationery in 1st gear... it only happens when accelerating at a normal road speed from a standstill in 1st gear... and its only in the last part of the clutch take up... (the last 1/4 or 1/3rd of the pedal travel)...

Its not noticable in any other gear once I'm on the move.. But it is obvious enough that passengers are aware of it.

If I do aggressive starts it doesn't happen - its only when starting of at normal/gentle road speeds.

I am 500 miles since a new clutch and a rebuilt gearbox.. But I must admit to having done some very aggressive starts since the rebuild...

Any thought/comments please?? Do other cars drive like this or does anyone know of any 'problem' that might cause this effect...

Jeff

Edited April 3, 2007 by jeff_hooper

[fmxa]

FWIW My97 started doing this a few months back - the pedal has been feeling a bit soft, so I just bleed the clutch but haven't driven it yet (too tired and dirty to drive after the work).

[ibandre]

I am having the same problem now, after I got the new uprated clutch put in. I was told it is either the slave or master cylinder that has gone bad. This usually happens when changing clutch in the Esprit. I just ordered them both from PNM engineering, and I am pretty sure it will be ok when fitted.

[fmxa]

Interesting - all my "judder" started after I swapped both slave and master cylinders, and I did have hell of a time bleeding the system.

[hasuSan]

Interesting - all my "judder" started after I swapped both slave and master cylinders, and I did have hell of a time bleeding the system.

I have the same problem, found out the AP pressure plate has deep scratches and fitted (shinny).

I had a hard time finding someone who can turn (take some meat out) the pressure plate (similar to turning the brake rotor). The pressure plate is expensive, I wish there is an alternative other than AP.

I found a local shop, he did an average job but not great. I put it back, works with no problem in all

gears. The problem I am having now is, the reverse gear. When the engine is cold, I have no problem engaging but when the engine is hot, I can't put in reverse. I have to shut the engine.

I changed my master but not the slave and still doing it. I bleed and replaced with hi-heat fluid (Motul)

and still doing it.

Maybe replace the slave....any idea?

[fmxa]

I just went for a drive and bleeding the system certainly helped, but there's still a bit of "judder" and sometimes it's hard to get in and out of gear. Think I'll drop her off with my local Lotus guy next week to have everything checked out ....

[Zhastaph]

Just gonna throw mine in the ring

I changed my clutch for the 3rd time {dont ask} a couple of months back and since then I've been suffering from Judder My symptons are 100% the same as Jeffs.

I'm pretty sure the cause is one of 2 things, either;

1. I went a bit mad with the grease on the input shaft which has since spattered all over the clutch plates

or

2. I forgot to tighten one of the gear box mounts

I initially thought it was the grease as the previous 2 occasions I had put very little on and noticed that the shaft was very dry and gooey after inspection next time around. Also giving the clutch a bit of stick seems to sort it out for a while. Last weekend I noticed there's a lot of movement in one of the gearbox mounts. I noticed that the thread has stripped on the bolt so replaced it. Immediately after this it seemed as smooth as you like, but that only lasted a day or 2 i've since looked at it again and found that the metal centre has been pulled from the bush. I'm currently waiting for a new one to turn up and will let you know the result .....

[Vulcan Grey]

In my experience clutch judder and brake "warped" feeling are caused by the same thing.

That is an un-even transfer of friction material to the friction surface. Pad material to rotor or clutch material to flywheel...

The problem usually happens over and over to some people and never to others. The problem is often behavioral.

IMO what happens with brakes is that people ocassionally need to stop really hard, after aggressive driving or when something unexpectedly jumps out or whatever. And then they sit there on the brakes at a stop light or whatever, and the hot rotor continues to melt the pad material and as it eventaully cools, it fuses in that spot (in the shape of the pad) to the rotor. This is the reason you never apply the parking brake in the pits after a track session.

Same thing happens with the clutch, after a really hard launch and some good clutch slippage, the clutch is released and the friction surfaces of the clutch sit there and fuse into the flywheel. As the layer builds up, it tends to build up higher in those spots again and again, and you feel the judder of the clutch skipping over the high spots.

With brakes you can sometimes re bed in the rotors by going through repeated and increasingly harder stops, never coming to a stop, and allowing the brakes to cool between stops. Then drive the car home without using the brakes, and let it cool. This technique can often get rid of the warped rotor syndrome, though sometimes an aggressive pad needs to be used to scrape down the high spots.

If you don't change the behavior, it'll just happen again.

I know of people that have been able to do the same with a clutch to fix the judder.

It involves heavily slipping the clutch and then keeping the pedal pressed and the clutch plates from touching the flywheel while cooling so the friction material doesn't fuse in spots to the flywheel.

If you wash your brake rotors with water you often can see the pad imprint on the rotor.

BTW never have a friction surface like a brake rotor or flywheel "turned" on a lathe by a machinist. These friction surfaces should only be blanchard ground. The grinding will provide a stronger, harder, longer lasting surface with more consistent friction. Machining a rotor with a cutting tool on a lathe will create weak peaks and valleys which are suceptable to damage by heat build up, and will wear very fast and unevenly.

[superdavelotus]

I was under the impression that it was distorted plates on a V8 clutch when it judders?

It could also be something broken inside.

When mine needs replacing I've found a place who can fully recon them with AP parts for

Edited April 5, 2007 by superdavelotus

[hasuSan]

I was under the impression that it was distorted plates on a V8 clutch when it judders?

It could also be something broken inside.

When mine needs replacing I've found a place who can fully recon them with AP parts for

[fmxa]

Update - I consulted some of our local guru's which lead to a late night slave cylinder removal and re-bleed - I now have zero judder when pulling away! Travis makes very valid points, but I drive both of my Esprits exactly the same (no hard launches) and only have (had) the issue on one.

[MKE40]

Going back into Dinosaur mode ,

I f I remember right, 50s and 60s cars were susceptible to clutch judder and snatch if the engine and gearbox mounts were sloppy, so there is reason to believe that this could be a contributory factor to judder on a later car as the Esprit................

Just a thought .....

Mike

[Rob C]

Recently, I have become away of a definate 'judder' when I start off from stationery in 1st gear... it only happens when accelerating at a normal road speed from a standstill in 1st gear... and its only in the last part of the clutch take up... (the last 1/4 or 1/3rd of the pedal travel)...

Its not noticable in any other gear once I'm on the move.. But it is obvious enough that passengers are aware of it.

If I do aggressive starts it doesn't happen - its only when starting of at normal/gentle road speeds.

I am 500 miles since a new clutch and a rebuilt gearbox.. But I must admit to having done some very aggressive starts since the rebuild...

Any thought/comments please?? Do other cars drive like this or does anyone know of any 'problem' that might cause this effect...

Jeff

Sounds like the spline from Gear box shaft running through the clutch may have been fitted dry..it needs to be clean and then applied special grease (factory) to use on the spline..some people use copper grease

regards Rob

[glynherron]

Sounds like the spline from Gear box shaft running through the clutch may have been fitted dry..it needs to be clean and then applied special grease (factory) to use on the spline..some people use copper grease

regards Rob

Hi Rob, and hope your well.....

I used copper grease on my spline and have been having some judder ever since the gearbox was fitted. I am now regretting this as It is maybe a factor??

While on the topic of grease, what is the special 'Lotus' grease?

Cheers

Glyn