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Hi guys.

I managed to bust my clutch or something clutch related a couple of days ago. I know I am going to have to take everything apart to figure out exactly what is broken but I was wondering if anyone could have a guess as to which part is the problem. The behavior has been a bit weird so far so I am not sure if it would be the friction plate, the pressure plate, the fork, the bearing or something in the hydraulics that is broken.

Here is the full story so far.

On the weekend I was driving with a friend who asked if my car accelerated quickly. Of course I said "it sure does" and at the next lights took off pretty quickly, not over the top, but just enough for us to be feeling the backs of our seats pushing against us.

Everything was fine up till the top of 3rd gear when I let off the throttle and went to go into 4th to coast. When I pressed the clutch it was very soft and went to the floor without disengaging. I had to just let it slow down in 3rd and pull to the side of the road and turn off the engine. I checked the fluid and it was quite low so I though I may have been lucky and just gotten some air in the line. After a few pumps I was able to get a little bit of pressure back in the pedal and was able to put the car in 1st but the clutch was still dragging a bit with the pedal all the way down. I got the car home in 1st gear and turning off the engine at lights but it was quite a long trip home.

The next day I bled the clutch. I didn't put too much fluid through it, only 3 or 4 fills of the master cylinder, but after that the clutch pedal firmed up quite a bit but it was still a bit softer than it should have been. I tested it and it had improved significantly but it was still dragging a bit when the pedal was all the way down. I decided to adjust the slave adjustment screw thing to see if that would get rid of the drag. After making an adjustment from about 1/3 to about 2/3 up the adjustment screw I tried it again but now it was disengaging fully but when I had the pedal all the way up the clutch was slipping heaps. I wound it back to 1/3 again but this time it was still slipping there then I put it all the way towards the engaged end of the adjustment and I was able to drive it slow on the flat but if I pressed the throttle a bit more or went up a hill the clutch would just slip like crazy.

The thing that is confusing me at the moment is the combination of the clutch not disengaging fully to start with but now not engaging properly and the fact that the pedal is so soft. I can't picture what is going on inside my clutch to cause these symptoms. I am thinking maybe something to do with the bearing or fork if it was able to go from dragging to slipping but then for the soft pedal thinking the pressure plate or the hydraulics. Maybe a couple of things have broken.

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Make sure the hydraulics are all working properly, it sounds like a hydraulic problem initially.

Check for leaks around the MC and SC and the hose as far as you can.

Lotus Esprit S4 - Work in progress

Porsche 924 Turbo - Parts chaser

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I'm with Rich.

i'd suspect something like salve cylinder, seals fail hence loose fluid but yo managed to get some pressure back , just not enough to fully disengage. Now the piston may be getting cught up by bits of the knackered seal and so not returning fully, hence the slipping.

Pull the rubber boot off the slave and check for fluid there, it shouldn't be there but I think it will be.

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Hmmmm, interesting - I'd be thinking master first. Back to basics though - set your fork adjuster back to where it should be - 12.5mm IIRC, and test from there. Could be fluid blowing past a worn master cylinder seal?

British Fart to Florida, Nude to New York, Dunce to Denmark, Numpty to Newfoundland.  And Shitfaced Silly Sod to Sweden.

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I'm with the above. The clutch is a real [email protected]#$% to bleed as it's horizontal, I jacked the back up, Steve took it off and held the cylinder upright. You can get a new master cylinder they're not expensive, I believe it's a 5/8 bore. I had my slave cylinder re-sleeved locally. I do all that first, and see if it comes back to normal.

Life is like a sewer, what you get out of it, depends on what you put into it. (Tom Leahrer)

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Thanks for the replies guys. I will have a look at the master and slave and do a more thorough bleed on the weekend. I was also thinking of how to tell if the clutch is slipping anyway without the input of the slave. If I can adjust the fork adjuster far enough so that it isn't touching when the pedal is up then test for slipping. If it is still slipping I will know it is something inside the clutch but if it isn't then it must be the hydraulics.

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If you adjust it to where there is a gap there as shown in your diagram, you may lose your pushrod and you probably won't be able to shift gears.

Adjust it to the proper spec as sparky suggested and make sure there is no preload on the pushrod and fork. You should be able to spin the pushrod without much effort but it needs to be touching the fork or it may fall out of the slave.

Edited by lotus4s

1995 S4s

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Did you try having somebody push the car with engine off, 1st or reverse engaged and clutch pedal to the floor? That should confirm a hydraulic problem.

As for bleeding if you do that with the slave off and held vertically and higher than the master, any residual air should bleed out.

DanR

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I did hold it vertically but it was lower than the master. I will try doing it higher next time.

I didn't do that check with pushing it in gear with the pedal down, but I did a test where I put it in gear with it jacked up on one side and the wheel off with no brakes and put it in gear. It didn't turn the hub with the pedal down so I am pretty sure it isn't dragging anymore.

It is just weird to me that it was definitely dragging to start with, enough to stall the car with the clutch pedal down, but now it is definitely slipping with the pedal all the way up.

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Justin.

When you have pressed the clutch peddle up and down a few times.... is the pick up on the peddle right at the top... in other words no play when fully up....if so then the master cylinder is not fully releasing the pressure in fully off position... this will cause the slip you have.... It may be the master cylinder seals are breaking down and causing this sequence of events or by your adjustment you have created this format.....As sparky say's set to factory spec and systematically go though each step.... personally i would recon the lot to eliminate all area's and have peace of mind...its not expensive and only a couple of hours work ....worth doing...

Dave..

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If the problem is Not hydraulic it will be the Cluch release bearing .

Last time had problem with my cluch (started some noise) and I replace both master/salve cylinder, but problem was the relase bearing.

I noticed the cluch fork showed moveing or how to call it more losed .

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  • 2 weeks later...

Well I have started taking everything apart now. I haven't gotten very far yet, just took the boot out and cleared a bit of space in my garage. I will report back once I get the gearbox out and can see what the problem is. My money is on fork or bearing.

Thanks for the advice guys.

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