Why did my clutch do that?

[dieselnutjob]

Context: SWMBOs Freelander TD4.

 

When I bought it the biting point was a bit low so I splashed on a new clutch master cylinder from Eurocarparts.  It is an LuK item.  The old one looked a bit damp where the rod goes in.

 

On the TD4 they are supplied prefilled with a push fit connector to join it to the slave, no bleeding necessary, but I think that this is a bit lazy so I called LuK and asked what they prefill them with. DOT4 they said.

 

Fitted new master cylinder and bled the system, I put maybe 1/2 litre of brand new DOT4 through it.

 

Clutch became absolutely lovely with biting point halfway down as it should be.

 

SWMBO very happy with clutch.

 

Drove it a around a bit.  Yesterday drove into London and out again including horrid jam on North Circular.  Clutch still lovely.

 

This morning drove up high street and suddenly clutch went to the floor and stayed there.

Hooked foot under clutch and pulled up, getting me one press to clear lights.

 

Same happened again, and again, and again.

 

Turned around to go home and collect dependable Peugeot.

 

Clutch started to improve a bit, now the pedal was coming half way up, and I was getting just enough movement to change gear.

 

Got home and clutch now totally back to normal and working nicely again.

 

Checked fluid reservoir, which is tiny.  Fluid is still at max.

 

Drove to work in it.  Went out at lunch in it, it's fine.

 

What happened?

 

I need this to be reliable.  If the clutch is dodgy SWMBO will put it through a wall or something.

[PiperCub]

Sorry if this is a dumb question but why did you bleed it when it comes all ready to fit as a complete system? 

 

Reason I ask is that while I've no modern LR experience, I recall reading somewhere - poss Car Maniacs mag? - that there were dire warnings against opening these effectively sealed systems for some reason (aside from the usual makers scare tactics of 'Thou shalt not.....' put about to dissuade DIY'ers).

[dieselnutjob]

Most Freelanders have a totally sealed system but the TD4 (the one with the BMW diesel) is different.  The slave cylinder is inside the bell housing and it have a bleed nipple on it, and the master has a reservoir which you can add fluid to.  The quick connector is just to make things convenient.

 

My thinking was that I wanted it to be as good as is possible, so no air in the circuit and not 13 year old fluid in the slave cylinder either.

 

Bleeding is not hard when you have a teenage son to press the pedal so that that's what I did.

 

And it all worked lovely for a few days.

 

I just don't understand how components can fail and self recover.  Something is going on that I don't understand.  I did read a report from another owner that his old clutch would go "over centre" due to being so worn and he had to pull the gearbox and fit a new clutch, but I don't really understand what that means.

[chaseracer]

I just don't understand how components can fail and self recover.

 

You've never owned a Citroen, then...? 

[sierraman]

Last time I bled a clutch it was due to a loose gland nut on the feed for the release bearing, nipped up with a crows foot fortunately

[dave21478]

TD4 clutches - a fucking misery, and no doubt. Mine is entirely new parts (master, slave, mech, disc and flywheel) and still needs bled once a fortnight.

 

There are a fair few folk on landrover forums with similar problems. Causes are many and various, with no one good answer. Air getting into the slave via dodgy connectors seems to be a common theme. I am pretty sure mine draws air in through the quick-release connector between master and slave.

 

Also, the design of the slave cylinder means that no amount of bleeding will ever get all the old fluid out. input and take-off for the bleed nipple are both at the top of a circular piston, so the rest of this circle is a low point where old fluid and various cruddy deposits accumulate. This crud leads to wear on the seals and leaks either fluid outwards or air inwards.

 

What ever happened to a good old fashioned lever and a bit of steel cable?

[NorfolkNWeigh]

Totally different engine ,I know ( Mondeo/PSA 2.2 ) but my Mrs' Freelander did this when the concentric slave failed. In the 2 years since we changed it and the clutch , the pedal has stayed down twice , the last time about 8,000 miles ago. It's like the locking , pas and stereo faults that randomly come and go, we just expect it to fix itself.

[Rocket88]

Just a random thought........could one of the seals occasionally be "rolling2, and then resuming their correct position?

[MarvinsMom]

i understand that the mark 1 freeloader and the rover 75 use the same clutch?

 

my rover 75 cdti did exactly the same thing, as the slave cylinder was shagged.

 

ended up getting anLUK clutch and master cylinder fitted along with the x-part freeloader slave cylinder.

 

certainly on the 75 these are plastic and utter, utter shit, i can imagine that this is the same standard fit bit on the landrover.

[Asimo]

This happened to my wife in the Subaru a few months ago. Pedal to the floor and stayed there. I rescued her with a car swap, drove home clutchless. Investigating, pulled pedal up, pumped a few times and completely back to normal, not happened again or even hinted at a problem.

 

Weird.

[twosmoke300]

It will be the concentric slave starting to play up I'm afraid

[gordonbennet]

Don't mind me asking, probably a dumb question but i've never seen one of these infernal internal slave cylinder jobbies, but then i've had autos for donkeys years.

 

When i had manuals i never had a problem with a good old fashioned slave bolted to the bell housing with a rod and lever assembly to do the business.

 

If a slave failed you could bolt another on in minutes and bleed it out in seconds, if the lever bent or broke as they did now and again, nine times out of ten you could wangle the bent one out and slide a new one in, again in minutes.

 

Far as i'm concerned it wasn't broke, so why the fuck did they fix it with something that appears to be of no improvement whatsoever, proves troublesome, and a right pain in the arse to put right when it fails which it will...is this just another example of why we avoid modern shit like the plague?

[oldford]

Had this a while back on one which we'd sold.  It was the concentric slave, there was a bit on it which would turn and i think that the pipe wore through, as it would turn it would sometimes end up in a position where the worn bit of the pipe was sealed and the clutch would work fine, then it would turn so that it was off the pipe and the clutch wouldn't work right.

[Des]

Would it be worth sticking a 1/2'' bit of timber under the pedal? Fault mightn't occur if the pedal isn't going the whole way, or am I being a bit last century?

[Eddie Honda]

I've never seen one either, but then I'm miles behind in automotive technology.

 

http://www.exedy.co.uk/media/54800/ref_0007_-_concentric_slave_cylinders_explained.pdf

 

So it seems the manufacturer can save a few separate parts, the laydees can operate a light clutch and the aftermarket can sell bucketloads of replacements??

[dave21478]

If you do get it replaced - use original LR parts only. Anything less is a waste of time and money and will not last long.

[dollywobbler]

Definitely sounds slave related. Had the same issue on my Discovery - easily accessible - and my Rover 75 - far less so.

[dieselnutjob]

If you do get it replaced - use original LR parts only. Anything less is a waste of time and money and will not last long.

 

What about these?

http://www.dmgrs.co.uk/products/land-rover-freelander-td4-all-metal-slave-cylinder-uub000070

[gordonbennet]

I've never seen one either, but then I'm miles behind in automotive technology.

 

http://www.exedy.co.uk/media/54800/ref_0007_-_concentric_slave_cylinders_explained.pdf

 

So it seems the manufacturer can save a few separate parts, the laydees can operate a light clutch and the aftermarket can sell bucketloads of replacements??

 

Thanks for that.

So as suspected, they fixed something that wasn't broke, and the fix is shit as effin usual.

[Eddie Honda]

Well to me it would be okay if they actually fitted it on the outside of the bellhousing somehow and made it a piece of piss to swap, but no, the wankers decided to put it inside. Now I'm no engineer, but I do wield spanners and if I think it's a cock idea to put it inside, then it is!

 

(But then I like the easily adjusted clutch rod on the Reliant Regal, or the too many rods throttle linkage on the old Regals and Rebels - BRING BACK RODS)

[billyboy406v6]

Just because a new component is fitted, it can still fail almost immediately due to poor quality control/faulty assembly ? Just changed handbrake cable on the v6 that was new last year ? WTF ?

[dieselnutjob]

Is it possible that fitting a new master and bleeding it is pushing the slave to a place that it isn't used to? If the slave seized in the out position then the pedal would just stay on the floor.

Maybe if I persevere with it it might free up, or if I leave as it is so that the biting point is nearly on the floor it might just stay in its "comfort zone". Anyway I scored a new Valeo solid flywheel conversion kit on eBay for £300 so I will have parts ready if/when it totally fails.

[dieselnutjob]

Night before yesterday I bled it again, and it made little difference, working but biting point 1/4" off of the floor.

Yesterday I decided to take it to a car mechanic mate for his opinion, and he directed me to "gearbox Dave" who turns out to be solid gold.

The wierd thing is that the clutch had overnight magically fixed itself again.

He told me it "feels like a dodgy master cylinder", and that if I wanted a new flywheel / clutch / slave fitted he would do it for about £200 which is an absolute bargain considering that you have to drop the subframe, both front driveshafts, propshaft, then transfer box (IRD) and finally the gearbox.

He said it's no big deal if you have a ramp and airtools. I like this guy.

 

Last night I cut the original master cylinder in half and and it appears to be about 18mm or 11/16" bore, so pretty close to generic 0.7" TR4 type generic Girling stuff, and there is actually plenty of room to fit one.

 

I think that I will figure out a way to bodge in a bracket to hold a generic metal master cylinder.  I just need a way to connect into the slave quick click connector thing (I have the one off the original master).  If the pedal can pull on a threaded rod then it can become adjustable so that the biting point can be where I want it.

[dave21478]

Low biting point is a common thing too, even when they are not failing. I cut the stud off my pedal and welded it a few millimeters further forwards not long after buying the car to make it more civilised.

When I replaced everything (clutch was starting to slip) I got a new pedal to revert to the old length of travel in case it did something bad by pushing too far on the new parts.

 

You can unscrew the quick release connector from the metal pipe on the slave side and fit something else - its just a normal flared brake pipe fitting so you should be able to make something up.

I trialed replacing the plastic pipe from the master and the quick release thing by removing the barb from the bottom of an old mater cylinder and braising a bit of copper brake pipe into it, flaring the other end and scewing it to the slave cylinder pipe with normal brake fittings. This worked well enough, but the copper pipe didnt like the movement of the engine, even with a loop in the pipe run as strain relief and eventually started leaking where it fitted to the master cylinder. My next effort was to be to replace the copper with a bit of flexi hose - apparently a motorbike shop should be able to make up a flexi any length you want with whatever fittings you need. I dont know why I never bothered - just lost interest I suppose and went back to the standard pipework and bleed it every fortnight. I can do a full bleed in seconds now!

[dieselnutjob]

Is there a way to join plastic to copper/cunifer?  If I could do that I would run copper from the master across the bulkhead and chop the original plastic at that point and join it there.

[dieselnutjob]

You can unscrew the quick release connector from the metal pipe on the slave side and fit something else - its just a normal flared brake pipe fitting so you should be able to make something up.

 

I noticed that and tried to undo it, but it is done up really hard so I need to buy a proper brake pipe spanner before wrecking it.

[dave21478]

I couldnt figure a way to join the plastic to anything else so it would withstand the pressure reliably.

 

Yeah, the screw fitting was mega-tight on mine too. I made a bit of a mess of the nut. I would quite like to cut it off and change it, as I am not sure its fully tightened any more but I have a cheapo pipe flaring tool that will only do copper, so I cant re-flare the steel pipe.

By the way, be careful with that steel pipe. it passes through a rubber grommit in the bellhousing and down to the slave cylinder inside, but where it plugs into the slave cylinder is really fragile - I could easily see it snapping if you get too violent with the pipework.

 

Those steel replacement cylinders look good. I havent heard of anyone useing them yet though.

[dieselnutjob]

I had a another look at this.  I think that the solution for the master cylinder is to drill through the heads of the captive bolts which the clutch pedal box uses.  I can do this from under the bonnet rather than under the dash which would be impossible.  If you stick a finger along the master cylinder under the sound proofing you can feel the bolt heads.

 

Once those two bolts have gone I can replace them with threaded rod to hold the clutch pedal box on the inside, and a flat plate on top of the sound proofing of the bulkhead in the engine bay.  Then I can bolt a generic Girling 0.7 inch master cylinder to that plate.  If it doesn't work I can just remove the plate and put the standard LR master back.

 

If I can then just tap into the plastic pipe or the back of the old plugin clip thing then I can try it.

 

If it is still unreliable after than then I will have eliminated the master cylinder and I won't feel so bad to spend the ££ on getting the gearbox out.

[UltraWomble]

Bizarre

Ive just posted about a friends TD4 on another thread - did exactly the same as you describe. They farted about with it for ages - went back to the main dealer a couple of times and much £££ spent - eventually cured at a local independent in Preston - Ill send Su a message and ask her if she knows what they did ( cost her £40) in the end.

[UltraWomble]

Su says:

 

 

It was the slave cylinder in the gearbox and a landrover specialist can repair it without dismantling it all.

 

 

Might help, might not.