Thread: d2 clutch hydraulics

ok ive put new parts in but am now not getting pressure to push the clutch plate ive bled it several times and have oil at the slave cyclinder can some 1 please help

Mate they can be an absolute pig to bleed. I had the clutch master and slave replaced on mine last Wednesday after the master started by-passing when I was driving down to Perth from Kalgoorlie a couple of days earlier. They had the old cylinders out and the new ones in in no time at all, but it took almost two hours to bleed the thing - and that was with experienced Land Rover mechanics at a very well known and reputable Land Rover specialist (not a dealer) in Perth. They told me that this is common with Land Rovers - and not just Discovery's. I can appreciate this, as I recently had the same problem bleeding the clutch on a Series III in Kalgoorlie.

Persistence, and slow, steady pumping of the pedal while bleeding seems to be the answer. And whatever you do, don't let the reservoir run empty while you're doing it - this didn't help when we were bleeding the Series

One thing that did seem to help on the Disco - they pressurised the reservoir very gently with compressed air while at the same time pumping fluid through with the pedal and bleeding at the slave. All they did was jammed an air nozzle in the top of the reservoir and held in place with some rag jammed around it in the opening. But only very gentle application of the air - otherwise you'll have fluid everywhere. It was only after they tried this on mine that they started to get some pedal pressure. It required three people - one pumping the pedal, one putting the air into the reservoir, and one at the slave releasing and tightening the bleed nipple as required.

They also tried applying vaccuum at the bleed nipple on the slave to suck the fluid through - didn't work.
Best of luck.

thanks

the car is up and running again, i had to give up and take it to the mechanics, who told me the slave cyclinder was put on upside down, i guss thats what happens when u let ur father put ur car back together, now for the next question where is the best and cheapest place to get a drive belt
and is genuine better that after market

Originally Posted by BMKal

Mate they can be an absolute pig to bleed. I had the clutch master and slave replaced on mine .. it took almost two hours to bleed the thing - and that was with experienced Land Rover mechanics at a very well known and reputable Land Rover specialist (not a dealer) in Perth. They told me that this is common with Land Rovers - and not just Discovery's. .. Persistence, and slow, steady pumping of the pedal while bleeding seems to be the answer. And whatever you do, don't let the reservoir run empty while you're doing it .. One thing that did seem to help on the Disco - they pressurised the reservoir very gently with compressed air while at the same time pumping fluid through with the pedal and bleeding at the slave ... It required three people - one pumping the pedal, one putting the air into the reservoir, and one at the slave releasing and tightening the bleed nipple as require ... Best of luck.

There seems to be a distinct problem with air ingress with these hydraulics. I put a new clutch in an 01 TD5 Disco and then had little or no pedal. I went straight for a hydraulic bleed and was getting loads of air. Had a quick look under the pedal box area and sure enough, the m/cyl was leaking. The answer to my problem, was the instant diagnosis. New mcyl on and crikey, struggled to get a better pedal than with the old unit. Kept getting loads of air, and i mean BIGGEST MOBS of air !! Impossible, how??

Whilst the mcyl was supplied by a NLRD, it was a Delphi Lockheed unit which i'm sure is a GP? I did note that the pedal sounded "sqwarr-ky" but i traced that to what seemed like an ultra dry piston in the mcyl .. i flicked off the rubber boot and sprayed a little crc past the piston retainer collar and the noise vanished. That didn't bode good in my mind, i imagined a dry rear seal that eventaully woud've chopped out .. ? It made no difference, stil kept bleeding tons of air. I tried MULTITUDES of bleeding combinations and NONE have been as successful (read, "still not good") as pressurising the resevoir. Any pumping of the pedal just makes the pedal worse.

I have in my kit a radiator adaptor that has a stepped rubber length that inserts in the radiator neck and u tighten the thread which pulls an internal taper up through thereby expanding the rubber until it seal against the neck, and then connect your pressure pump to it. A dangerous piece of apparatus that nearly got binned when it let go with a huge explosion on the very job for which i bought it, as could not purchase the correct adaptor. In any case, it proved to be the ducks guts for this experiment. I've spent over 4hrs now trying to bleed this clutch.

Pumping the pedal when bleeding only seems to introduce air.

The trick was to pressurise the system, i used about 8lbs and undo the bleed nipple, purge the air, release pressure, a few pumps of the pedal and back again. About 3 times i did this and now can get no more air out.

But the pedal is not sufficient to get gears. Only missing out by the inch or so of spongy travel i'm getting at the pedal.

By leaving the system pressurised, no worries, i can get gears but i'm talking now about that same inch i gained in pedal travel is exactly how far it "catches" or the clutch takes up when the pedal is released from the floor. Not a lot but waaaaay better than any deal i have struck thus far.

I've been on a test drive but i must start it in 1st (pedal to the floor of course) and then i'm in business, it will change without clashing for the rest of the gears but is blocking out on the change down because of insufficient pedal travel or clutch disengagement.

I've tried rebleeding using the same method but can no longer extract any more air.

By pressurising the system and gaining the best ever (i would now concede as "acceptable" given the BS i have been through) clutch feel, i reason i have lost something, somewhere, when the new clutch went in. An A/M jobby sold to me by the same vendors of the Cl mcyl. There are no adjustments at slave or master. Maybe i haven't been around much but this is the 1st m/cyl ive seen with no pushrod adjustment.

Or have i still got an air pocket as yet unpurged? Or, another thought i have, is there missing contact between the slave cyls pushrod and the clutch fork? When i pressurise the system, it shunts the pushrod out that mm or 2 and there's my pedal? Any small deviations in travel distances at the fork should be absorbed by the spring behind the slave cyls piston which would adopt a position of contact? I'm less likely to believe there's an issue there as i'm sure i had to gently force the slave into its hole as i felt the plunger push back in its bore.

Why am i getting heaps of air when using the pedal to bleed? It has to be coming from only one source. The m/cylinder. And there's more possibilties there to explore as to why but i gotta go.

Cheers, Danny.

Gday Danny,

Not sure about the air problem, but I am just going thru a glutch replacement with mine and mine wasnt so much the clutch, but the push rod was bent and the clutch fork damaged..
You dont have the same problem do you, even tho the push rod ois moving are you getting full travel or has it or about to push thru the fork itself...

Just a thought..

Cheers Ean

Hi Denny,
I think you still have air in the system.
Im not sure why the LR hydraulics are a pig to bleed and wont go inot my theories here. But try this. (dont laugh)
You will need an assistant.

Make sure the reservoir is constantly being topped up as the clutch pick up line is only half way down the res.
Have your assistant open the bleed nipple (about 3/4 turn) at the slave and make sure your have a tube going into glass jar so you can see the fluid and air coming out.
(make sure the res. top is clean and have rag and water handy)
Seal you lips on the res. top and blow. Have the assistant tell you when air stops. You can use compressed air but you only want about 3 psi and be VERY good and sure of the seal.

This method takes 10 mins from start to finish. (you dont need to blow for ten mins)

Cheers

Originally Posted by Ean Austral

Gday Danny,

Not sure about the air problem, but I am just going thru a glutch replacement with mine and mine wasnt so much the clutch, but the push rod was bent and the clutch fork damaged..
You dont have the same problem do you, even tho the push rod ois moving are you getting full travel or has it or about to push thru the fork itself...

Just a thought..

Cheers Ean

G'day Ean, i replaced the clutch in this one due to what sounded like an awful thrust bearing noise but it turned out to be a dry spiggot bush, i also noted that the spiggot end of the input shaft was not completely engaged in the bush and still had a mm or so of 'unused bushing'.. in all my dealings non landrover, i'm used to witnessing the input shaft completely penetrating the bush or bearing. I judged my distances and didn't instal the new bushing quite as deep as the previous instal.

Anyway, i digress. The fork, pivot etc looked all to be of good order. Of course i cant see any fork or rod movement once assembled as this is all contained within the bellhousing and as such cannot be viewed, unlike most other vehicles, non landrover, where some of the fork exits the bellhousing.

Thanks for your comments Ean, cheers Danny.

Originally Posted by strangy

Hi Denny,
I think you still have air in the system.
Im not sure why the LR hydraulics are a pig to bleed and wont go inot my theories here. But try this. (dont laugh)
You will need an assistant.

Make sure the reservoir is constantly being topped up as the clutch pick up line is only half way down the res.
Have your assistant open the bleed nipple (about 3/4 turn) at the slave and make sure your have a tube going into glass jar so you can see the fluid and air coming out.
(make sure the res. top is clean and have rag and water handy)
Seal you lips on the res. top and blow. Have the assistant tell you when air stops. You can use compressed air but you only want about 3 psi and be VERY good and sure of the seal.

This method takes 10 mins from start to finish. (you dont need to blow for ten mins)

Cheers

Thanks Strangy but you'll see i've outlined this method already in my earlier rant, only i avoided the need to get brake fluid on my lips

I'll tell u what i have done, with no success !! was a reverse bleed method. I adapted a plastic soft drink bottle and inverted it like a intravenous drip and applied gentle air pressure to push fluid back up through the slave back into the main resevoir. I had it on good authority that this is the only method that works and has worked on each and every occasion for the man that explained it to me. The theory was that the trapped air is pushed back into the resevoir.

Only the fluid would not gravity feed even tho' the drip was held high and contained about 1.5L of brake fluid, so i added some air pressure. I made the fluid move but seemed not to achieve the results i was praying for.

I probably moved 2 or 300ml of fluid, maybe i should try for more ..

The issue is air bubble/s resisting the purging process due to a confluence of a high running clutch line and air ingress through orthodox mainstream methods usually employed to bleed. At least that much makes sense although every other conspiracy theory has its merit too ..

I just need another inch of pedal travel, as already explained i have near full pedal travel, it's just the 1st inch or so that feels spongy and by this exact amount makes gear selection adverse.

Cheers Danny