MatraSport Forum

I have recently noticed that  my clutch pedal has to go very far down to engage, and it's become hard to get some of the gears.
this has happened in a fairly short period of time, so at first I suspected a leak , but it looks ok...

New Clutch? or can it be adjusted?

The clutch is self adjusting. There might be air in the clutch line.

I agree with Bart... try bleeding it. But it could also be a seal in the master or slave cylinders - depending on which one is worn it may or may not leak.

So.. all a sudden air can sneak its way into the system?

I have experienced the same problem a few years ago, the problem was the slave cylinder. This should be easy and cheep to fix, but on my Murena the slave cylinder was EXTREMELY difficult to dismount. The slave cylinder is placed in a "tube" in the casting of the bell house and after 25 year of corrosion the two items were like welded together.

Hans

Did you fit a new slave cylinder? or is there a repair kit available ?

Once i had a funny thing with my slave cilinder. That was with the 1.9 engine with the original 1.6 matra slave cilinder. It got air in the system when i rev over 5000 rpm. Whenever the engine was hot or cold, just rev it over 5000 and instandly air. Then i bleed it and get lots of bubbles. After i bleed it i could drive 1000's of miles (1600's of km ;)) without any trouble, as long i keep the revs below the magic 5000rpm.

It happened several times, so i am very sure when it appear. i just can't explain it.
after i put a new seal in the slave cilinder it was solved.

he he... it could very well be...
The problem has only been evident since I got my car back with throttlebodies fitted... and to be honest.. it has done 5000 rpm (and above) A LOT more often since then :)

I had the same trouble exactly as Bart_Matra and Matra_Hans, and as you know, it was Your Car!!! 4500rpm was the magic figure for this 2.2 engine. A new clutch slave cylinder cured it, but looks like it's back again. Try a new seal, the slave cylinder is not very old. It is weird though isn't it?  ???

Yeiks!!!
you weren't supposed to find out that I reved the old girl that hard!    ;D

So air in the system then...

Just put a wooden block under the accelerator ;D

Now where's the fun in that?   ???

That will improve fuel consumption too :D

and a wooden block under the clutch pedal. No more spongyness :D

Let her rip Krede it's how it's meant to be!!!!

Happy to oblige!  ;D

I got a new slave cylinder from Simon.
To get the old cylinder out I ended up heating the housing much more than I liked with a blowtorch, I only did that after spending several evenings trying to get the old cylinder out in a more civilized way.
The old cylinder turned out to be rather corroded inside so a repair kit would not had helped me.
Hans

I had the slave cylinder off the car today... no problems in that.. (but as mentioned its fairly new)
I could find NO sign of any leaks or wear, and I bled the system to see if any air had gotten into it....
But to no effect!!
So Im a bit puzzled

Do you have any leak of brake fluid at all? (on the level in the reservoir)

The master cylinder would be next, then. Leaks from there are visible on the carpet below the clutch pedal which will appear wet (thanks Lennart! ;D )

Nope... Np leaks

Update..
During the journey from work the clutch became less and less effective.. until finally not being able to disengage drive altogether!! not a pleasant experience in cross town traffic!!

Still no leaks are evident, but surely air must be entering the system somewhere..

Ill replace both cylinders for good measure... as I haven't been able to find any repair kits anywhere..

Now... the hard part will be getting the car to the workshop without any clutch what so ever.

If there's air in the system the pedal will be 'spongey', but you may have worked that out already?

Well.. clutch action simply deteriorated, until it wouldn't nothing happened when pressing the pedal!!..
So the car will be out of action for for the next two weeks, as I Do not expect the new parts to arrive from Simon before I go away on exercise this Thursday...

Damn.. now I have to take the bicycle to work!.. BuuUUUUHhhhUUUU! :( :( :(

I feel so sorry for you. REALLY! Now that you have that new toy installed. So it still feels hard as it should? any noise from the clutch area/gearbox? if the bearing is crushed the fork can't act on the clutch spring. or the fork could be bent... or it could just be worn down so the fork can't reach long enough to declutch.

There's no harm done buying spare cylinders as you'll probably need them eventually, but I think you should inspect the clutch itself.

Has it become harder lately, by the way? I remember your clutch pedal was quite soft when I tried it back in october 06 when we met at Lennart's - at least compared to mine. I found it hard to beleive first time I was told, but when the clutch becomes harder, it's normally because it's worn. If you look at how the spring acts on the mechanism you can understand why.

Why not take the gearbox out now that you can't use the car anyway?

Im pretty confident that its a hydraulic problem... the way that it came about..in such a short time, but still not all at once... HAS to be a broken seal or some other mishap inside  one of the cylinders.

If Its not a Hydraulic fault, The car will be put away until I come home in May.
At that time, It's my plan to have the gearbox down, and attempt Roys 5 gear conversion..this the "kit" also includes new and improved bearings.... and there is some serious "hissing " and "scraping" noises coming from the gearbox when "engine braking"..... Might fir a new clutch while I have it open... and.. and....

Bahh! - a few years ago, I drove my Peugeot 106 1.1 from Belgium to Le Mans without a clutch ... (thats 7 Payage booths and Paris, if you're interested)  :-)

as if it wasn't enough of a challenge to drive 2x1400km in a 106 1.1 rollerskate - and I actually did that trip twice in that car.

ok, I did manage to hit Paris at 5am on a Sunday, so there was hardly any traffic.


But having said all this, I hope you get that clutch sorted real soon - using a bicycle in Denmark in January is about as unpleasant it gets.


/Lennart

Knowing how tall you are..... that's just cruel!!!

Update :
I have replaced the slave cylinder, but it has not improved anything.I still only have a tiiiiiiiny bit of clutch "bite" in the very bottom..
I have bled and bled the system, but it still feels very much like there is air in there still.
Can it be that it has to be bled "reversly"? .. have heard that other clutches need to be.. but as far as I can see the highest point on the master cylinder is where the fluid goes towards the slave.

I find it hard to believe that the clutch itself would wear so quickly that one can TELL that it does so, and thus my next cause of action is to replace the Master cylinder....as soon as the rubber seals for the plastic pipes that OBVIOUSLY has to be bought separately with no mention of this in the spare catalogue... will arrive.   

 

Update :

Found the fault...
Turned out to be the master cylinder... .. and yes... it was leaking... .. Only I hadn't noticed as the leak was in the end of the cylinder... witch is INSIDE the car... .. where I hadn't bothered to look... ::) ::)

Been there ;)

Good you found it. So you are running again?

I sure hope so!!!..Since I'm taking it to Herning later today to watch The Superbowl with a couple of mates from my time in Iraq... would be a crappy to get stuck halfway.... "clutchless" ... while the beers just get warmer and warmer!!!  :o :o

I finished replacing my clutch slave cylinder today, which was leaking.

I took the old one apart, which is easy - the piston just has to be pressed out of the cylinder from the opening (e.g. using a small screw driver). To my surprise, the seal was not really worn, but there was a lot of dirt inside, and I think the leak was actually caused by the dirt and not the seal. It can enter through the rod end, which is not sealed that well, but it's difficult to tell.

Has anyone found spare seals for this part? I know a kit was offered by Talbot for the Tagora. The cylinder seems to be very easy to repair, and even simpler than the master cylinder.

Photos of the procedure:
http://gallery.dinsen.net/v/biler/Murena/technical/clutchslave/

- Anders

Looks like a standard brake cilinder seal to me.
Is it also 20.6 mm 13/16" ?

The dirt Looks like sand in the oil, but how does it get there.

Through the rod seal, I think. The cylinder sits quite exposed and whenever the pedal is released, a bit of air is sucked in on the back side of the piston. Small particles can make their way through and will then work down into the cylinder. In my case the cylinder was very dirty inside. There's probably very little to do about this - except fit a protective cover around the cylinder, rod and clutch release fork. Or be prepared to service the cylinder with regular intervals?

Anyone remember this discussion?

My clutch master started leaking again - it was only 1 1/2 years old and should have lasted a lot longer. When I did the clutch slave, there was a lot of dirt. I thought it came in from the outside, but I was wrong. I had a good discussion about the issue with Roy over e-mail, and we found out that it was likely to be a problem caused by dirt buildup inside the system. This can happen with silicone brake fluid if the system is not cleaned completely. Here's a photo of the result - no wonder it leaked!

(http://gallery.dinsen.net/d/3227-2/DSC_0505.JPG)
(this is the piston in the master cylinder, in case you don't recognise the part ;) )

In this case, I think the problem is caused by not stripping and cleaning the new master cylinder before fitting it. It was probably well greased when I got it to prevent corrosion - and here's the result :(

I'll clean it again, refit it - and let's see if the problem happens again. The great thing about silicone brake fluid is that it protects all seals and - in theory - the system should be maintenance free, even if the car is left unused for some time.

- Anders

WOW, If this is caused by reaction of silicon and DOT4, I stay at DOT4.
Silicon can be better for the seals, but if DOT4 can keep the car on the road for 25 years there is no need to change.
I think it will be difficult to get all traces of DOT4 out a older system, and only if the system is completely renewed, better not to go that way.

It's not a reaction between DOT4 and DOT5 - more likely left over HC based grease in the cylinder combined with normal wear. The piston has worn down a bit and is 0.5 mm oval (notice how bright it is on the photo). I assume that the aluminum particles from this wear, combined with the grease has lead to this buildup. DOT5 and DOT4 brake fluids are generally miscible, but shouldn't be as it will nullify all the advantages of the silicone based brake fluid.

quote
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I assume that the aluminum particles from this wear,
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That could be it.
Its the same dirt you had in the slave.
Hope for you it wil stay leakproof for a while, but with a oval cilinder it wil be a matter of time I think.
Better try to find a new cilinder

Well the piston doesn't seal anything, and I've fitted new seals. They were slightly worn from working in the dirt, so I could just as well do them now that I had the thing apart. The cylinder is fine inside.

When I put it together, I'll avoid any grease, and only lubricate it with the brake fluid. That's the correct way to do it, and this is the big difference between DOT5 and the other "DOT's": Silicone brake fluid lubricates - other brake fluids don't. And the brilliant thing about the silicone is that it doesn't make the seals softer as HC-based oils do. Last, it doesn't absorb moisture, so the brake fluid will never need to be replaced as alcohol based fluids do. Finally it's non toxic. A properly cleaned and prepared brake system with DOT5 should be virtually maintenance free - mine wasn't obviously! ;)

Job is done now, inbetween shopping and looking after the children. Two more photos:

(http://gallery.dinsen.net/d/3230-2/DSC_0517.JPG)
Clean piston with new seals.

(http://gallery.dinsen.net/d/3233-2/DSC_0518.JPG)
All the parts, and a few from the old unit I replaced 1 1/2 years ago.

I'm rolling again :D

Amazing that you got it done then!! ;)

I do wonder if it is bossible to obtain some soet of repair kit for these cylinders...

This firm delivers brakemaster repairkits for Volvo 340.

http://www.biggred.co.uk/

This kits have the 20.6mm seals that fits the clutchmastercilinder.

I think there are a lot more possebillitys to find the right seals.
a lot of peugeots have also 20.6 seals in there brakemastercilinders.
Look in the brakesection of this site and see howmany fit the 20.6 description.

http://www.pugspares.co.uk/Main.asp (temp of line for maintanance)

I didn't find the seals seperate for sale yet.

Well, you can do a lot of tricks with rope :P

Seriously, I like multitasking ;)

About repair kit, yes it would be brilliant if someone could come up with a kit, but it would really have to include the piston, which scrapes on the sides of the cylinder when the pedal is operated and wears down to oval shape. I used the seals from a kit for a Volvo brake master cylinder I found in Biltema - unfortunately that they don't stock it any more :(