Clutch pedal adjustment

[Chillidoggy]

On the S4, it's 170-175mm for the clutch, and 160 - 170mm for the brake pedal. So theoretically both pedals could be adjusted to the same height, depending on whether the height average is adhered to.

The S4s is 175 - 180mm, hence my 5mm difference, clutch pedal being higher.

[s4simon]

For reference my clutch pedal is at 170mm-ish and my brake pedal 160mm-ish.

 

.

 

 

 

[ramjet]

That's a whole heap more than mine.  

Thanks guys.

[DanR]

On 14/03/2017 at 19:17, ramjet said:

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?

Sorry Michael, I didn't get back to you. I've been immersed in a bathroom-laundry renovation.

What Changes said is the way to go. When I had my gearbox out I marked the position of the fork to the bellhousing window for every 5mm of thrust bearing travel. From memory I think there was 20mm in total. Once I had everything back I adjusted both the master and slave pushrods to give me that 9-10mm of travel. I can't recall if that met the workshop manual guidelines for adjustment but I got the pedal set to what I think is its best position.

One thing to be very careful of is avoiding bottoming out. The fork has a weak spot which will break if there is any bottoming out. I made a 3mm mild steel plate to strengthen that weak spot. One end has a hole large enough for the adjuster thread and the other end is pop riveted to the fork. I used an oxy to bend the plate exactly to the bend in the fork.

You can see the weak spot next to the the hole in this photo. Why Lotus didn't run the webbing all the way past that flat spot is one of those anomolies that leaves one pondering why. Much like the way they surrounded the petrol tanks with water retaining foam.

http://www.lotus-spare-parts.co.uk/esprit-renault-clutch-fork-87-to-97/

 

[Sparky]

Roger, apart from measuring, have you done anything about this yet?  Here's what I'd do.

I'm assuming the correct bore slave is fitted?  Adjust the master cylinder pushrod to achieve specified pedal dimensions.  Then you can make the specified adjustment at the bellhousing.  This adjustment is to help prevent excessive clutch wear.  It will not affect pedal stroke or height.

[Chillidoggy]

As long as the clutch pedal height is set correctly, then the fluid displaced is always the same. That fluid displacement is what dictates slave cylinder piston stroke length, not the clutch fork adjuster: The 9-12mm specification there is to prevent over, or under, engagement, and has no bearing (no pun intended) on the clutch release movement. When the clutch releases, its spring action pushes the rod back into the slave cylinder, but only so far as the adjuster allows. Clutch fork adjustment dictates where the slave cylinder piston commences and ends its stroke when the clutch pedal is depressed, that is all.

Bottom line:- Set it up as per the Service Notes.

[ramjet]

I have set the pedal heights all to the manual and gone through the clevis adjustment and the rod adjustment on the brake pedal. Took awhile, but I'm a lot happier.

I have to check the total travel at the clutch fork. That is the last thing I have to do now.

[s4simon]

Now that I have the seats out it's a lot simpler to see in there.

Square on shot of the pedals.

 

[DaKa]

I would concur with the lastest image above.

From the floor up about 170mm but from the pedal to the angled front section as per the first image much further 190mm plus.

PS.

Thanks for your pics above as I've noticed my left foot rest is missing - something else to add to my list!

[Cushing]

Hi all, I'm still a bit confused about this, I've had issues with my clutch in respect to burning out the thrust bearing after 500km. The clutch seemed to be slipping very slightly when I bought the car. I replaced the slave cylinder and tried with the adjuster nut 12 turns etc but there is no play between rod and arm, in fact it's under  a lot of tension.   my clutch pedal measures about 200mm to the floor and it's hard up against the stop on the pedal box,  I did notice another hole slightly lower on the pedal, which hole should I use ?  

88 Turbo

[ramjet]

Something is not right there Stephen. I have only just got the distance as required by the manual in the footwell. I do not get the prescribed amount of movement at the slave cylinder when depressing the clutch. (I'm short by about 2mm), but the pushrod can definitely be turned when the clutch is in its relaxed position.

I remember that some members on here have said that one of the pedals can have two holes in it. One marked C for clutch, the other marked B for brake. I am not sure if this pedal is in the clutch position or the brake position in the car. I do not have the option on my S4. Each pedal has only one hole for attaching whichever clevis. Might this be something that is wrong?

If you can't move your pushrod at the slave end, the bearing will always be up against the pressure plate and under load. That will be why they are burning out.

[CarBuff]

2 hours ago, Cushing said:

 I did notice another hole slightly lower on the pedal, which hole should I use ?  

88 Turbo

One hole is marked C for clutch, the other is marked B for brake.  If you can't read the pedal marking (WHAT?  you don't have a mirror?????  ) note the brake pedal connection and verify that the clutch clevis pin is in the 'other' hole on it's own pedal.

[Cushing]

Checked everything, I have a few mm play in the pedal, it's connected into to top hole C , but if I have the slave cylinder adjuster set according to the service notes then the thrust bearing is hard against the clutch plate springs. I've set it so I can just turn the slave rod with my fingers. We'll see how that goes.

 

Thanks for the reply's 

[Chillidoggy]

15 hours ago, Cushing said:

Checked everything, I have a few mm play in the pedal, it's connected into to top hole C , but if I have the slave cylinder adjuster set according to the service notes then the thrust bearing is hard against the clutch plate springs. I've set it so I can just turn the slave rod with my fingers. We'll see how that goes.

 

Thanks for the reply's 

 

If you push the clutch fork end by hand, does the operating rod move back into the slave cylinder?

[Cushing]

Hi Chillidoggy, no it does not, it seems to be under pressure, I did notice the thrust bearing that burnt out was about 5mm thicker than the OEM one from Sjsortscars, but I still cant figure out why it's starting to operate the clutch if I set the slave cylinder screw according to the Service notes. I haven't started  the engine yet to see how it performs. 

[Sparky]

The screw will have no effect on normal clutch operation; it's there just to prevent excessive wear that would damage the flywheel.  If you can't push the clutch arm and pushrod back (use a lever between bell housing aperture and arm), then loosen the slave bleed nipple and try again.  Then post your result please.

[Cushing]

OK, not home until Monday, keep you posted :-)

 

[Chillidoggy]

Musing on this one: The clutch hydraulic system is effectively 'locked'? Unless there's a non-return valve in the line between the master and slave cylinder, then there is no running clearance in the bellhousing/clutch plate area, because you should be able to push the slave piston back into its cylinder. Are you absolutely sure that the flywheel, clutch assembly, release bearing, and release fork are (a) fitted correctly, (b) in good order and (c) the correct parts for your car?

I wouldn't be at all surprised if you have to remove the gearbox out to discover what the problem is, but see how you get on with Sparky's advice first.

[Barrykearley]

Springy bits on the clutch plate whatsit

[Chillidoggy]

Fingers?

[Barrykearley]

Yeah them bits....

id be making sure the hydraulic bits work properly first - really easy to check with two people

[CarBuff]

3 hours ago, Barrykearley said:

Springy bits on the clutch plate whatsit

A local S4 owner had similar issues.

 

The pressure plate fingers (fitted by the P.O.) had bent/broken and caused shifting issues over time. We checked/bled his clutch hydraulics with no joy, so the car was sent to the local Esprit specialist and that's what he found.

[Cushing]

Tried to move slave cylinder but not able to unless bleed nipple  undone, wasn't expecting it to move to be honest. Installed new exhaust and started her up and gear-shifts and clutch seem fine, so leaving it set with no threads showing on the slave adjuster.  I did have one thought though, the clutch had been changed before I bought the car and I've had the engine out and gearbox off so all looks good to me, new thrust bearing and slave etc, but looking at the slave cylinder rod it looks new and shiny, this did not come with the new slave cylinder,it was on the car when I bought it, maybe it's not correct for the car, does anybody now how long it should be ?

 

Steve 

[sailorbob]

See my second post.

 

Edited November 14, 2017 by sailorbob

[Cushing]

Mine is 125mm long, maybe this is the cause of all the trouble ?