My pedal opperates nearly on the floor ,I have had a new clutch about 6k miles ago and it has always been the same .Is there any way that I can adjust the actuation position of the pedal?do I have a problem with the masteror slave hydraulic cylinders?
regards John
John,
If it’s working OK that’s the best position - it’s quite uncomfortable with it higher. Of course it’s not good if it’s too low - ie need to pump the pedal. You can adjust the clearance at the master cylinder to nearly zero to make it somewhat better, but otherwise you may have a problem somewhere (but unlikely if it’s always been like it).
On LHD cars the flexible clutch hydraulic tube can be old and soft and cause this problem.
There’s quite a lot of posts on using different sized cylinders for one reason or another in the archives.
Gordon
Check the clutch fluid level.
The red plastic hose is a possible problem as discussed above. On LHD cars they tend to melt from the exhaust heat, or just get old and crack and start to leak. Some of of us Yanks have installed braided stainless clutch lines to solve this. The stainless line can act like a hacksaw if allowed to rub on anything, so cover it with a piece of split rubber hose where it rests on or near anything. Its not a bad idea to do this for the plastic line to keep it from wearing through on the chassis.
Also check to make sure the master or the slave is not leaking fluid. If the master leaks, there will likely be fluid on the carpet in the footwell.
It is also possible the slave itself is loose in the fit of the bell housing bracket. The slave is held on the bellhousing with a circlip. After many thousands of miles, the fit loosens up from wear. Adding a second circlip to hold it in place takes away almost all of the slop.
It could need adjustment on the pushrod at the slave if the pushrod locknut has come loose. Instruction on how to do this is clearly illustrated in the shop manual.
Happy Lotusing!
Dan Wise
Elan Dhc/S3-Super Safety
45/7279
Make sure the system is bled really well and the pushrod properly adjusted. Having determined that, have someone in the car to slowly push the pedal down and it should move in sync with the pushrod out of the slave, after the play in the pedal is taken up. You could also have a cracked fork.
Greg Z
'72 Sprint
When I pump the clutch pedal I get some abnormal results ,the operating point moves to differant places thro the pedal travel .When I bleed the clutch “er indoors” did the pumping ,not a good idea she was more conserned about the neighbours new curtains that the pumping which made her leg hurt .I shall get a competant person ,a man and do it again .wiil post results
Hi John,
I quote your original posting:-
“My pedal opperates nearly on the floor ,I have had a new clutch about 6k miles ago and it has always been the same”.
Was it like this prior to fitting the new clutch? (“and it has always been the same”)
If not, the depth / length of the new clutch, could it be shorter than the original & thus require more pedal movement until the thrust release bearing comes into contact with the clutch. If so only a high degree of adjustment will compensate and it could be that a longer thrust release bearing carrier would be necessary.
Appologies if I’ve missed something somewhere along the line.
John
John, it sounds as if the slave cylinder is floating a bit too much. There is a small amount of back and forth action on the slave and I eliminated all the motion on mine by wrapping the slave with a 14g copper wire opposite of the circlip. My slave cylinder is now stays in one spot and the engagement point doesn’t change.
Greg Z
'72 Sprint
I think I have an hydraulic problem ,master /slave cylinder.
I get judder at low speed takeoff [see earlier posts].I renewed the clutch about 6K miles age ,just to cure this problem which it diddent .I dont know the age of the master/slave clutch cylinders although there is no apparent fluid loss. I shall probally change them both. I
m waiting for a ramp to clear in a friends garage to investigate more.
Do you totally trust the guy who put the clutch in for you?-Could it be that packing clips are still under the fingers?
just a thought!
Good point ,I put the clutch in ???
Always blame the fitter, thats what they did when I was working
There are also two different types of clutches you can fit ; with or without centerpad, and release-bearings to go with them ( - flat or round) If you mix them up, you can get into what you describe.
Dag
My local parts supplier needs to know the number cast onto the slave cylinder,I have given him the girling number 64067950, from Garaths list of everthing fitted to Lotus and where they were soursed from[what a great list this is ,it has save me lots of time and money ]
Has anyone got a slave cylinder handy and can give me the number cast on it
Hi John,
I have a spare clutch slave cylinder.
Number appears to be 64673347.
Regards,
Peter.
I have bleed the brakes and there is no noticeable differance in pedal operation .I shall replace the two cylinders one at a time starting with the master
Could someone check their clutch pedal movement and tell me if there is any change in feel /clutch operation or position the clutch engages when they give the pedal a second /third pump
Hi John,
Actuation point and feel are consistant in my Sprint regardless of how many times I pump the pedal. This is with the car parked. Pretty sure it’s the same whilst driving.
Steve.
John,
I have, not long ago, replaced the seals on both the clutch master & slave cylinders and fitted a new aeroquip flexible hose at the slave cylinder end. I have bled the system several times with a pressure bleeder and with her indoors (who is also part owner!) doing the pedal pumping. Working on a slave cylinder with the exhaust in place is a b%$&er of a job on a +2.
On first touch on the clutch pedal the damned thing operates almost on the floor. After 2 or 3 pumps the actuation point is a lot higher. (makes for interesting take offs in traffic as clutch actuation position feels almost random). I am convinced that there is still air in the system but for the life of me I can’t get it out.
I replaced the seals because the old ones were leaking and the rubber flexible hose because it had a gash in it. The clutch actiation point then, was about 2/3 of the way up off the floor and consistent. That’s what I want to get back to.
I think my brake bleeding problem comes from the position the car is in when I am bleeding the clutch (it’s nose up on ramps). I am going to take it to my local garage to get it on a hoist and maybe even slightly tail up and see if that makes any difference.
BTW - the clutch is properly adjusted.
Regards,
Hamish.
I had total clutch failure on my S4 when the master cyliner dumped all the fluid in to the footwell
When I replaced the master cylinder and new braided pipe I noticed that the (Hmm not sure of the correct name here) bit where the cylinder rod joins the pedal was very worn. About 1.5" of pedal travel was just the slack in the worn bits being taken up. After fitting some new parts the clutch action is a lot better.
It is easy to check this. Just go head down in the foot well with a torch (flashlight) and operate the clutch pedal by hand you will soon see any play in the system.
Suggest you look at the push rod and the fork where the pin goes through the fork this often becomes oval. The ratio of the pedal then amlifies this .020 of clearance to half an inch.
Richard
I had this problem, then after a 10 year layup I tried the clutch and after some effort and it not moving at all it went straight to the floor so I had to re-build the master and slave cylinders.
This revealed the problem - BOTH cylinders were seized in their extreme positions so the previous problem was probably down to them not returning completely to their place of rest and so the full volume of hydraulic fluid was not being used.
Afterwards it was much better, but I reckoned I could go one better still - the original push rod from the clutch arm to the master cylinder is non-adjustable - if it were adjustable then I could increase the travel of the pedal - this might make the pedal a little higher, but a small price to pay for better clutch disengagement.
How to do it? From ebay I bought a new cylinder for a Landrover (Defender I think) which has a threaded push rod and I bought a clevis fork and pin threaded the same (5/16 UNC I think). You can’t use the Landrover master cylinder because the mounting holes are too wide and it is 3/4 bore not 5/8 and this might work but it is a 40% increase in clutch effort. SO just switch the push rod. You will have to trim the push rod by trial and error, but with clevis fork it is longer than the Lotus one
I had to relieve part of the back of the clutch arm because the clevis fork I bought stopped the arm coming back as much as I wanted, but just 10 minutes with a Dremel did this.
Result - lots of travel, good clutch disengagement.
I also replaced the plastic clutch hose with a stainless braided one and made a heat shield to fit on the bell housing to shield it from the exhaust.
Total cost - about ?20 for the pushrod - and I still have the Landrover one less push rod that could be sold.
Stainless hose cost about ?28.