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ramjet

Clutch pedal adjustment

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So I have had to do the clutch slave cylinder on the car. In putting it back together, I have checked the manual to make sure everything is adjusted correctly. The manual states to back off the pedal upstop (if fitted - no) and measure between the floor carpet (compressed) and the bottom of the pedal. Measurement should be between 170~175mm. Mine measures about 140mm.

Either the clutch and brake pedal are massively out or the manual is wrong. I doubt the manual is wrong, but something feels off.

Has anyone else ever worked on this? I have little confidence in adding about 35mm of 'more' travel to the pedal. That would put it a long way from the plane of the brake pedal. Or maybe I have about 35mm of uncompressed underlay and carpet in the footwell?


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

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I just checked section JF of the manual for the brakes.

Brake pedal should be between 160~170mm. 145 for me. So I would say someone has adjusted everything and gotten it quite wrong.

Can anyone tell me if all 3 pedals sit on about the same plane at rest, or if the clutch and brake pedals sit a bit higher than the throttle pedal?

Thanks.


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

Opinions are like armpits. Everyone has them, some just stink more than others.

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I was just questioning based on what I have in front of me.


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

Opinions are like armpits. Everyone has them, some just stink more than others.

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Pretty sure, but I can check tomorrow. Any easy identifier to look for?

I have just thought about it and my clutch has always travelled right down to the floor. Based on the manual, I'd now hazard a bet that it has been set up incorrectly. As is the brake by the looks of it.

Back to the manual specs tomorrow methinks.


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

Opinions are like armpits. Everyone has them, some just stink more than others.

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Is your S4 fitted with an airbag?

If not the obvious answer for your travel issue is that the master cylinder clevis is connected to the B (brake) hole in the pedal arm, not the C (clutch) hole. IIRC the difference in the holes equates to ~35mm of travel.

 

PS, don't ask me how I know about this issue, please. :blush:

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Atwell Haines

'88 Esprit

Succasunna, NJ USA

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I asked you NOT to ask...   :P

 

Turns out, guys fill up the first hole they can find.   Even if it's the wrong one.

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Atwell Haines

'88 Esprit

Succasunna, NJ USA

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6 hours ago, CarBuff said:

Is your S4 fitted with an airbag?

If not the obvious answer for your travel issue is that the master cylinder clevis is connected to the B (brake) hole in the pedal arm, not the C (clutch) hole. IIRC the difference in the holes equates to ~35mm of travel.

 

PS, don't ask me how I know about this issue, please. :blush:

This. I discovered this numpty mistake when changing my master. Setting it to "Clutch" made the pedal about 10 times lighter too. 


Vanya Stanisavljevic '91 Esprit SE | '91 Elan SE | '97 XK8

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I think I have a bit of sleuthing to do then.

1) My clutch pedal has always been heavy.

2) As I have said, I don't have the correct clearance to the floor as per the manual.

3) Neither does the brake pedal.

Looking under the dash as well last night after getting my head into the footwell, I can see the typical blistering of paint on the plate going through into the bonnet area that you get from leaking brake fluid, but nothing is wet.


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

Opinions are like armpits. Everyone has them, some just stink more than others.

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What's your adjustment on the slave push rod? That affects the travel too.

 


DanR

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Hi Dan,

If I set the slave correctly, it is tight at that end. The pedal is only 140mm from the floor and the upstop has disappeared into the metal of the pedal box. I think this has all been mucked about with to get all the pedals on nearly the same plane without regard to the master cylinder travel.

I do get free play in the pedal when it is in the released position though. That would seem to indicate that the master cylinder is returning all the way back wouldn't it?


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

Opinions are like armpits. Everyone has them, some just stink more than others.

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3 minutes ago, ramjet said:

I do get free play in the pedal when it is in the released position though. That would seem to indicate that the master cylinder is returning all the way back wouldn't it?

This is your primary and most important setting for your system..... Work from there..  To get the peddle down position to the book  ( or where you want it)  shim the master cylinder away from the bulk head..  This will allow the peddle to go to the floor etc..   after that the up position will be as is .... you can use the stop screw ( if fitted ) to prevent excessive slack at the top...   Once the clutch is set , adjust the brake peddle to match with its own height adjuster ..  Job done peddles set...

There are many settings and systems you can use to customise peddle weight,  height  and travel....  its all about what you want..

hope this helps... 

D

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My pedal has always travelled all the way to the floor. Reading the manual, the pedal should stop short of the floor (based on the master cylinder travel) if the floor to pedal distance has been set correctly. This is how I read it.

Dave, are you saying that the firstmost measurement is the pedal to the floor when it is depressed or released? I am thinking you mean released based on your post?


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

Opinions are like armpits. Everyone has them, some just stink more than others.

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I'll take some measurements and pics of mine when I get back home.  Been out of the state on business for 8 weeks.  Hopefully will take a look this weekend.  I repaired my slave cylinder many years back, had no issues re-installing.  My clutch has always been heavy, and from memory when I tried various other S4 cars in the UK they were all the same.

But Danny is the master here and knows a lot more than me about techni-stuff.

 

 


Simon  (94 S4)      My Esprit will be for sale in late 2017

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I have never considered my clutch heavy until I pressed the clutch in Goldacre's S3 that Steve Taylor had prepared when it came over. Incredibly light.

I didn't pay attention to where the pedals sat compared to each other.


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

Opinions are like armpits. Everyone has them, some just stink more than others.

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I maintain you would do well to set it all up as per the Service Notes, and see how you get on. They give you a 5mm pedal height tolerance. The clutch pedal on my car (which incidentally uses a S4 clutch arrangement) is about 5mm higher than the brake pedal. They are both set up as per factory, but to my preference. So there is some room for tweaking on the pedal height, but if you move outside the tolerances you risk difficulty in changing or selecting gears, or damage to the clutch.

As for the heavy pedal, remember your S4 clutch has a lot more torque to cope with than an S3.


Margate Exotics.

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I did think of that Ian. Does make good sense and one of the first things that crossed my mind.

My intent is to take everything back to the manual specs.


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

Opinions are like armpits. Everyone has them, some just stink more than others.

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3 hours ago, ramjet said:

Dave, are you saying that the firstmost measurement is the pedal to the floor when it is depressed or released? I am thinking you mean released based on your post?

Yes the released, position..  Your peddle travel when connected to the correct hole on clutch peddle is fixed.  ( the later Esprit's to memory only had one hole so that may not be an issue for you. )  Where the peddle sits in relation to the floor is controlled by the the M cylinder stroke length..  If yours hits the floor then the adjuster may need moving out bringing the peddle higher until the cylinder stoke stops the peddle before it reaches the floor, but you must make sure the free play remains at the top.

Irrespective of all this what you need to achieve is the clutch release distance.. This is usually 9-10 mm travel on the thrust bearing. As long as this is achieved then the clutch will function.  Any more will over stress the cover springs which in turn will effect the clamp loading.. any less will create clutch drag..

To memory the earlier cars had a longer peddle with a .65 m cylinder.  The S4 on had a shorter peddle with the .70 M cylinder. this was part of the larger cabin claim which gave you more leg space...  The penalty was the weight of the peddle (heavier).. Also I believe later cars had an increased clamp loading, so heavier still ... This is why an SE set up feels so much lighter that say an S4s..

You can manage all of this to get a lighter peddle with position / travel you desire by changing M cylinders and pivot points on the peddle.  The only constant must be the 9-10mm movement on the clutch release distance..  As long as this is achieved the how is irrelevant..     If you go back to basic physics theory on leavers / ratio's, the rest is just practical application..    

If i can achieve a light weight peddle with a high clamp loaded 550 ft lb torque clutch on a 10 mm disengagement stoke, all within the standard cylinder fitments, there is no reason why anyone should not be able to obtain what they desire with relative ease. Sometimes things can get over complicated by looking to hard at them , a clutch is fairly basic..

        

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Thanks Dave. :) 


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

Opinions are like armpits. Everyone has them, some just stink more than others.

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Mine all appear to be the same height.  Never altered in my 15 years of ownership.

pedals.thumb.JPG.289ac877820a66bdc7deece2ad5114b7.JPG


Simon  (94 S4)      My Esprit will be for sale in late 2017

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Hmmm. Mine certainly do not match the setup heights in the manual.


All we know is that when they stop making this, we will be properly, properly sad.Jeremy Clarkson on the Esprit.

Opinions are like armpits. Everyone has them, some just stink more than others.

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