Thread: dramas after clutch replacement

Friction plate will go in the wrong way round....that will cause this, but so will air in the system so make sure it is bled out well.

JC

Disco-94, can relate to your problem, I drove our latest Disco, which we had just picked up all the way from Brisbane to Cairns with that same problem (clutch would not disengage), yes, it is true, I kid you not the experience took 10 years off my life, but that whole thing is another story.
Along the way after a night stopover at Rockie, I once again checked that the clutch slave was bled thoroughly (for the 5th time in 24 hours) and noticed that when the clutch was depressed with the engine running there were faint squeaking noises emitting from the bell housing, immediately I thought a collapsed pressure plate diaphragm, only problem was when I had heard this before in another vehicle it gave the opposite symptom, clutch slipping badly.
Upon arrival back in Cairns and after a journey so filled with fright I'd rather not remember, the Disco went into the workshop and gearbox was hauled out, I had already purchased a new replacement clutch kit ($320 at our local LR specialist), imagine my surprise to find a broken clutch release fork, only one leg of the fork was pushing against the release bearing assembly, the other leg was in the bottom of the bell housing, the original clutch was still in good nick but was being replaced anyhow, along with a new replacement and modified release fork. The old guy at our LR spares place said that in all the years he had been selling bits for Discos that was the first fork he had seen that had failed on the leg where ours had failed, they normally wear through on the fulcrum ball socket or the slave cylinder rod socket he said.
So after all that may not be helpful to you, but, 1/ if you are sure that the slave and master are working ok and are bled thoroughly. 2/that your release bearing assembly was fitted correctly with the little metal shoes that interface between the release fork and the bearing correctly in place.3/ that the fulcrum ball has not punched through the release fork at the socket or at the slave rod socket, then as has been suggested by justinc you may have the friction plate in back to front, but I'm not sure if it would give that symptom.
BTW, a testament to the strength of the Disco ('97 model) gearbox is, despite 1900klm of crash gear changes did little more than destroy the nylon bush at the base of the gearchange lever,syncro's still working great, no strange noises, oil was drained and inspected there were no big hunks anywhere, about the same amount of "metal fur" on the plug as I had experienced with my last Disco at gear oil change.
Looks like for you maybe gearbox out again, I would recommend a change of clutch fork anyhow unless you know it has been done, it is a real weakness on the Disco and when it fails not a nice feeling, and I certainly do not want to be in that position again, good luck with your search.

great, thanks for your replies guys!
got a new slave cylinder today and clutch is working fine now, I think the pushrod was a little on an angle going in, the old slave rubber cover was quite worn and loose.

Only other thing I have now is that it is not going in gear very easy while moving and trying to select a lower gear, i.e. going in 4th or third, approaching corner, going in neutral and slowing down I cant select second until going very very slow....

is that pointing towards a gearbox problem or does the clutch need to be worn in a little or ..... ?
Anyone got any suggestions on that?

Thanks again!!

Things that may have an effect on normal, smooth, easy gear changes......1/ check that the gearbox is not filled with normal heavy 80/90 gear oil, the box was designed to run ATF which is fairly light and this has since been superseded by a specially developed lighter grade gear oil, (I use the Penrite version of this special oil), you would not believe how much difference it makes to gear changes, especially cold gear changes. 2/ I have found that unless the bushings, springs and all the parts that make up the gear lever mechanism into the gearbox are in good neat fit condition this can also have an effect on how easily and accurately you can change gear, in other words check for excess "slop" in the gearstick movement.Both these things singularly or combined could be the cause of your problem, things I unfortunately know from experience.

I do run 80W90 oil in the gearbox, and have done so for years.

The thing really is that before taking the gearbox out and replacing the clutch everything worked perfectly.
I only replaced the clutch because I had a nasty, horrible extremely leaky rear main seal and had to take the box out anyway.

Let me sum it up again:

Monday: replace slave cylinder, bled the system, clutch engaged and disengaged, but gripped fairly early, i.e. lifting my foot off the pedal just half a mm and clutch engaged, and changing into 2nd and 1st gear while moving was quite hard/impossible until moving very slow.

then it stood in the driveway for a day

Now: when starting in neutral I cant get it in gear, when starting it in gear I only move the foot off the brake and the car goes like an automatic....

Do I need to bleed the system again?
Can a faulty damper be the issue?
Should I replace the master cylinder as well?

I am tempted to think that it is a hydraulic issue, but what does everyone think about the early gripping of the clutch> Is there a way to adjust it in a hydraulic setup? (it is a "peformance clutch", can that have anything to do with it?)

Sorry about all the questions, don't know much about clutches ....
Thanks for all your help!
Simone

sound like the rod on the slave cylinder is too short

This sounds like the exact symptoms the disco I recently bought had, I assumed it was going to be either the slave, master or clutch fork buggered.
I changed the slave, didn't do anything, got a blank for the master so could test that, sound. Which put the fault in the box.
Took it out a few weeks ago and found that the upper slipper pad had been lost off the fork, when you push down the fork pivots before contacting the release bearing and then continues.
With an uber bled system there was JUST enough travel to disengage, but anything off perfect and it wouldn't, also shows up with a pumping of the pedal working too.

I hadn't seen this before, but it sounds like the same issue.

That said, there is a common assumption that when you change the slave or master, the other tends to go because it is working or being worked harder. As I said above, I got a bleed nipple that fitted the master from local place (PBR on NE Road) which allowed me to lock the MC off and put some pressure on. It was rock solid which made me think that it was in working order.

As far as oil in the gearbox, my knowledge is that the R380/LT77 have a pump and this is very unhappy with thicker oils, hence the ATF (and why it has a filter above/underneath the drain plug). Engine oil may be thin enough to not murder it, but I'd suggest going to ATF.

Thanks guys....

Well, the too short pushrod theory also crossed my mind (along with adjustments on the clutch pedal) but couldnt find any adjustments on the pedal and the pushrod can actually only be changed when the gearbox is out - does not come with the slave cylinder, and as it was working fine before I don't think it is possible that it is too short....

regarding the slipper pad, well.... excuse my language...
Not too sure though when and how it would have come off since I just had the box out and cleaned and inspected everything. I thought it all looked in good working order, there was a heap of oil in the bellhousing to start off with since the rear main had been leaking badly, so I degreased it all and eventually greased all pivot points including the slipper pads, at which stage they were all in their place.

When you say you got a bleed nipple for the master cylinder - what exactly do you do? i.e. take pipe off, put bleed nipple in, pump it, bleed it? do you really need to bleed it or could you just find something that fits that thread and block it off?

Have spent all day (well a good few hours at least) bleeding the system and got another whole heap of bubbles about 3 or 4 times (especially after raising the front), and it did indeed drive well (clutch engaged kinda early but not right at the floor) and gear change went fantastic (pretty much as it did before taking it apart...) up to third, then I had to stop at an intersection and it was a little hard getting it in 1st (but I still have the center console out and gear lever is just the metal rod), then got it up to third again, and couldnt go into fourth or second or first until I stopped.

So bottom line is it starts off working fine(ish) and then rapidly deterorates to not being able to get it in gear with engine running at all

ARGH! Hoping at this stage not having to take the box out again, will try a new master cylinder next week and see how far we get!

Gearbox oil- will change over once the operation of the clutch is sorted....

Thanks heaps again!!