mk1-forum.net

The problem is when I press the clutch pedal it works a few times a d then becomes solid and won't compress?

Here is what I have done so far:

I thought it might be the Master cylinder so I striped it down and fitted all new workings including rubbers springs ext I thought the copper pipe leading from the master splinter to the connector might be blocked so I made a new one with the pipe disconnected and a bottle under it the fluid flows a treat. It's not the master cylinder or the copper pipe.

I thought it's might be the master slave cylinder so I bought a new one, fitted it, bled. it. It worked a few times the. Bang ! Clutch goes solid again. I have tried bleeding it the old fashioned way 2 (pedal down screw up ect ) and a single person bleed kit but nothing?

The only thing I have not changed is the rubber pipe leading from the screw connector, to the master slave cylinder but my thinking is that if it was bugged air would get in and make the clutch spongy not hard?

I have had the engine and gearbox rebuilt, the rest I have done myself. It's due to go in for a fnal set up at the garage before the key is turned, I just don't want to look a bell end because I can't set up a clutch. Is the an issue with the clutch setup inside the housing that's causing this or am I missing something? The gap in the throw is also correct.

Thanks in advance

Yours frustrated to heck !

Sully

Given what you have changed out (and one of my first thoughts), I'd say it would be the rubber flex hose. They swell on the inside and more or less, pinch off.

A bit of a side issue, but this is exactly why BMC fitted the over-throw stop, you know, the one that it seems most people don't bother to refit.

Is the clutch arm returning fully when it goes solid or is it still engaged ?. Do you have the return spring fitted (could be over throwing if you are pumping the pedal rapidly without a spring fitted) ?. Have you adjusted the over throw stop correctly ?. I still wouldn't rule out a mechanical issue if these items aren't correct. Obviously eliminate the hose first but also check the set up.

Cheers, Al valid points, . I will change the flex hose. When I bought the car the set up for the clutch was pretty rubbish anyway.

The clutch was moving freely last night, that's what's confusing me ? It works a few times then just stops ? the clutch pedal stops at the uppermost position and I cannot apply pressure.

I think I might disconnect the brake master cylinder pipe and connect it to the clutch see what happens when I press it (after I have bled the master slave cylinder, the spring is on so its not overthrowing?

This has had me in knots for a whole two weeks, I would happily buy a new master cylinder if I thought it was not working correctly but after rebuilding it will all new parts I cannot see what could go wrong with it apart from what I have changed? The issue was the same with the other master slave cylinder I stripped and replaced all the parts on the old one then went and bought a new one as I thought it was that.

The stop and throw set up is straight forward enough, I just thought I was overlooking the obvious ?

Thanks for the input, it much appreciated

To verify/eliminate the hose, when the clutch goes solid again, crack the slave cylinder bleed screw (probably best to have someone else do this while you have pressure on the solid pedal). If the pedal is still solid then it's the hose (or master cylinder but I think you've already proven it's ok). If the pedal goes to the floor then the hose isn't blocked/collapsed. Worth a try before you start swapping things around again.

Just another thing, although you say the clutch pedal is at the top when it goes solid, what position is the actuation lever in ?, ie. is the clutch jamming in the engaged or disengaged position ?. Could be jamming on the primary gear splines for some reason but then I guess it would doo this every time, not after a few operations.

My favourite by a mile would be a collapsed hose that is not allowing the fluid to drain back as it should.

M

Quick update I just got home it was still solid so I bled the master slave cylinder, the pedal now moves but is still quite stiff and disengages the clutch very slowly i.e the push rod moves the slave cylinder back into the "normal position very slowly. It appears the clutch (within the bell housing) is being disengaged.

I cannot feel any lumps or bumps on the hose, but I am about to strip it down and change the hose anyway.

Sully

All those who said it was the hose pat yourself on the back . There was a small hole in it that must have been letting in the air/Fluid escape. You can only just make it out. I shall post a pic for you all to see. Whoever had fitted it in the past must have twisted it when they put it on, must have created a pressure point.

Sully

Sully2908 wrote:Whoever had fitted it in the past must have twisted it when they put it on,

Many of the hoses have ribbed/braille lines down them...
... this is so that BLIND mechanics can still do the job "properly"...

Ian

Good work Sully and glad it's sorted. But goes to show, never assume, check everything.

ianh1968 wrote:

Sully2908 wrote:Whoever had fitted it in the past must have twisted it when they put it on,

Many of the hoses have ribbed/braille lines down them...
... this is so that BLIND mechanics can still do the job "properly"...

Ian

Bhahaha,,, so even you (who we have already established needs glasses) would be right But yes, this is a very good point and indicator. I can still see (just) and the hoses I get seem to have a white line down them, I just make sure that's straight.

Yep, I was convinced the hose was OK. trouble is now I have a problem with the fuel pump ! It never rains. Just pours I will post another thread to ask the questions.

Sully

Here is the hose, if you look just above the number 9 you can see two marks, this is where the air was getting in, twisted hose caused me no end of drama.

Sully