rough clutch release

[iggy]

ive had my A type overdrive gearbox refurbed and fitted it back into my mk2 2500 with a new borg and beck clutch kit plus hr release bearing new bushs fitted for the cross shaft checked the cross shaft pin and lubricated up with copper slip, new gearbox mount plus new cross member poly bushs, stainless braided hose from master cylinder to slave cylinder, when the car is started from cold the clutch peddle comes up nice and smooth as it should but after only driving a mile if that the clutch peddle will not come up smoothly theres no loss of fluid and ive fitted the slave cylinder push rod back in the same position centre hole of the cross shaft lever where it came from, any ideas whats wrong why would this only happen when the engines warmed up?  

[OBE]

I'm interested in any answers to this also .. my Stag displays almost exactly the same symptoms ..
The peddle comes up in a series of juddery movements if released slowly, makes hill starts a bit of a hit or miss affair for smoothness.
Bringing the pedal up more quickly seems better.
It's all perfectly smooth in operation when the engine is cold, or indeed if engine is not running (hot or cold)

As my engine and box are probably coming out this winter it would be nice to know what bit I need to be looking at for a cure.

cheers all

[Davemate]

Same here, mk1 saloon all standard.
New seals in master and as far as I could tell slave was ok.
I have however now got a slight leak from the slave so that will be changed on Sunday.

Engine cold or not runing = nice smooth action on the pedal.
Engine hot = juddery pedal,only the last inch or so of travel,when depressed.

Once the slave has been changed that should rule out hydraulics.
I can drive for the first 10 min,it doesn't matter wether I do one gear change or loads,after 10 min the pedal goes juddery at the bottom.

[Nick Jones]

I think it is the release bearing carrier sticking on the sleeve.  Did you grease it (right kind of grease and sparingly) on reassembly?  This is something quite alot of them do. The TR boys suffer from it as well and seem to recommend the brass carriers as a cure.  Not sure whether anyone does a brass carrier that is correct for the saloon though.

You may want to live with it for a while and see if it resolves with use as taking the box out on these is never an attractive prospect!

Nick

[Steve P]

Ditto what Nick said,

On my Vitesse,(2.5 engine and saloon box with j type o/d)the clutch was very notchy with the steel bearing carrier.Sort of on or off with nothing in between.

I found a spare brass one in my garage and its been as smooth as it should be ever since.
Steve

[nicmk1est]

if its down to the carrier,,,who got the tools to make them,was there a post on here regarding a person who had lathe and milling machine?

[Davemate]

1555 wrote:

if its down to the carrier,,,who got the tools to make them,was there a post on here regarding a person who had lathe and milling machine?

I could ask my man with lathe
I'll try and acquire a standard one for him to copy ---if anyone has a spare I could borrow  ;)

[iggy]

don't remember greasing the sleave, dam it don't want  to take the box out again

[iggy]

ive got an aerosol can of grease and copper slip would I be able to spray some grease on the sleeve if I removed the starter motor

[junkuser]

A bit risky Iggy.
Spraying lubricant near the clutch not a good idea.

[ferny]

Deffo not the spray can, it'll go everywhere! You want the thinnest smear of a high temperature grease really. Bearing grease would probably be more than fine as well. Can't imagine how you'll get it only where you want it without taking it apart.  :-/

[DJB_Harvey]

You can try and put some sort of grease on the carrier / nose with a tye wrap with a bit on the end and poke it through the vent slots on the bell housing ... Tricky but can be done

[iggy]

il give it a go with the tie wrap through the vent slots thanks for the advice lads

[esxefi]

not very helpful for people with the g/box in situ but a lot of modern cars have quite a large clearance in the bearing carrier,relying on the bearing to centralise itself on the diaphragm fingers when the clutch pedal is pressed.

I noticed this on the Toyota w series boxes where the carrier body has a plastic liner(glass reinforced nylon)and is a sloppy fit on the g/box nose.
it makes sense to do it this way.

so machine out your steel carrier and it will be ok.let the bearing do the work.

[OBE]

Thanks for replies, my engine and box are coming out this winter for other work so will make sure the carrier is in good condition and lightly greased before reassembly, cheers.

[Davemate]

DJB_Harvey wrote:

You can try and put some sort of grease on the carrier / nose with a tye wrap with a bit on the end and poke it through the vent slots on the bell housing ... Tricky but can be done

Would it be the end of the world if I put a 10mm drill through the slot to make a hole to give me a better chance of success. I'm only talking about drilling a hole I'm not going to enlarge the compleat slot

[Davemate]

I tried squirting some lithium white grease through the little slots, it made a tiny difference.
Today I bit the bullitt and decided to remove the gear box and have a proper look.
First thing I found
Some wear on the carrier,the input shaft on the gear box did have some grease on it but it felt sticky.

And some wear on the presure plate


A quick trip down to mr Picton to ask if the worn carrier would cause the problem,resulted in him saying he doubted it but it who could say (dizzy)
He explained that it was normally the presure plate wearing out that causes judder. He gave me different presure plate to try and told me to use cv joint grease on the gear box shaft and put it onto the face of the release bearing so that lubricates the preasure plate fingers.
Once back together I went for drive for about 15min and so far the clutch seems good, normally after 5-10 mins the judder would appear, tomorrow I'm going to Clacton so it will be a good test.

[iggy]

sounds like its sorted Dave hope it goes ok tomorrow, mine had a worn pressure plate,no problems pulling away from stand still, I had the fly wheel re faced lightened balanced new pressure plate, clutch plate, release bearing,gearbox refurbed  now there's no noise inside the car but I cant pull away at junctions from stand still properly it really does get bad when the engines got up to temperature, the thing is I don't remember seeing any grease on the gear box shaft when I took it out, did you put grease on the shaft before you put the gearbox back in.

[Davemate]

Gavin I may well be over at Steve's on Sunday,if I do pop over I'll bring my tub of cv grease if you want try  greasing things up a bit !  ??)
I'll also bring my can can of spray lithium grease if you want to try that first

[iggy]

ok Dave thanks il try that don't really want to take the box out again

[Davemate]

It's been over a week and all still seems fine  :) (that will will now be the kiss of death)

Iggy
1)      Is yours still working ok Gavin ?
2)    have you replaced your pivot pins yet ?

Gavin drilled a 10mm ish hole in the bottom of the bell housing and poked a greased up bit of wire around to lubricate the clutch bearing as opposed to removing the gear box,I'm sure he will elaborate as to the exact place to drill the hole  ;)

[iggy]

yeah Dave the clutch is working as it should nice and smooth will be replacing the clutch clevis pins Saturday hopefully thanks for the advice on them, wasn't at home during the week been working down in Ramsgate kent, for any one who's interested in greasing the the clutch release bearing carrier in situ I used a 20mm starrett cutter ( hole cutter ) and cordless drill a 350mm artist brush a magnet on an Arial type extension with a light in it, the hole I drilled is aprox 100mm back from the flange of the bell housing and off centre by about 100mm up the starter motor side of the bell housing  I can give more accurate measuremends if needed, the light fits in the hole the same time as the brush covered in cv grease so you can see the  carrier and nose of the shaft, put the grease on 3 or 4 times in between running the engine using the clutch and putting it  in and out of gear finally I got some grease on the front of the clutch release bearing its self using a thick tie wrap, obviously the car needs to be jacked up on axle stands so you can lie on your back and do it you must wear goggles while cutting the hole, I fitted a rubber grommet after finishing, the bell housing is about 6mm thick wear the hole was drilled so in my opinion only shouldn't do any harm  :)

[TedTaylor]

Thought I would readdress this posting following something we found when trying to improve the clutch on Woodie, our RBRR car.

The car has always in my ownership had a very poor clutch - short travel low down and stiff and jerky.  This was despite it coming with a small diameter slave cylinder which should have improved things.  
At first there was only a very small amount of movement low down and because the clevis for the operating arm was in its lowest position I moved it up one hole which improved things slightly.

While Gordon and I were having a good check over things we gave the clutch operating system a really good inspection because we were on the point of considering a complete clutch change.  With one person inside the car pushing the pedal it was obvious that there was little movement of the arm which was strange considering the small bore slave and operating arm position - until we saw that when the push rod into the slave piston was moved by hand ....... there was about 7mm of free movement!

Although there were washers in place as spacers it was obvious that there were not enough so after a bit of careful measurement we added more washers (on a temporary basis) to move the slave towards the push rod.  After adding about 6mm thickness of washers to bring total spacers to about 12mm AND moving the operating arm back to the lowest hole we found we had a clutch that worked OK.  Still a little a little 'short', and jerky at times which improved as the RBRR progressed but clutch was now acceptable.

Next thing is to make up a proper spacer (12mm of washers offends my engineering sensibiliities :-/) ASAP and experiment with moving the operating arm up a hole.  Then remove the gearbox to check the clutch thrust which from is feel its I am sure still sticking slightly as has been suggested previously in this thread.

MUT

[Jason]

My TR6 suffered the same jerky clutch, especially when warm. It made travelling in stop start traffic a real pain. In the quest for a decent clutch I replaced the lot - mechanical and hydraulic components, but the real culprit was a combination of a worn carrier and clutch cover "fingers" that were deeply worn. The TR6 set-up is slightly different to the 2000 so my fix isn't entirely relevant - I went for the phosphor bronze carrier and no anti-rotation pin (as per TR2/3 spec apparently) but apart from a very slight whine in neutral, it's excellent. I just need to chase out an ignition gremlin now - that, I suspect, is a dodgy plug lead.

[Davemate]

Ted,if you have got 12 mm of packing to move the slave cylinder nearer to the cross shaft,then I'd say you've got something wrong down there.
Possibly the cross shaft bolt has sheared and the shaft has spun a little but it's still being held by the Remains of the bolt.
If the cross shaft arm is pointing down then there should be little to no play,if you arm is facing towards the front then I'd suspect slippage of the shaft
On Radder's gertie we had the slave cylinder piston almost pop out due to shaft slipping,the clutch worked fine but you could just make out the piston tip poking out
If you've had the box out and checked the cross shaft bolt by removing it then I appologise for talking crap  ;D