Reckon I have a clutch problem

[Raider]

This will sound strange but bear with me.

I rebuilt the original engine in my very early Mk2 2000 and refitted it 100 miles ago now.

Been out for  run today and there's some back firing/reluctance to pull from low speed but by eck it will fly after that. Timing and ignition problem I reckon.

But - after a 25 mile run coming up to a junction, car in second gear (maybe first) with my foot on the clutch it suddenly cut out whilst lurching forward. The car restarted no problem but selecting a gear was very difficult to start with and the clutch pedal felt to be a long way down and not doing a right lot.

I was able to get a gear and drive away but then had the same problem as I pulled up to my drive and manouevred to reverse in - car cut out, restarted no problem but difficult to select reverse :-/

[dazzer]

Sounds like slave or master cylinder, mine would intermittently do this. Great pedal one minute then nothing or in between. Then it would be ok again for months. Eventually stripped both as no mechanical probs and now fine for years. Bleeding is an art use a pressure type bleeder.

[piman]

Hello Raider,

does pumping the pedal bring the pedal back up? My first thought was that the taper pin had broken?

Alec

[Raider]

Thanks guys - I'll look at it over next weekend.

I used a pressure bleeder when I put it all back together but no harm in having another go.

As the engine has now done 100 miles I plan to retorque the head and change engine oil and filter so I'll bleed the slave cylinder while the oil filter is off as it will be much easier.

[piman]

Hello Martin,

look at the angle between the clutch fork actuating arm and the slave pushrod, if it's greater than 90 degrees then the pin is probably OK?

Alec

[Raider]

piman wrote:

Hello Martin,

look at the angle between the clutch fork actuating arm and the slave pushrod, if it's greater than 90 degrees then the pin is probably OK?

Alec

Thanks Alec.

Just had a quick look but it's not easy to see without jacking the car up etc but I would say it's more like 80 than 90. It's certainly not more than 90

[piman]

Hello Martin,

I hope I'm wrong but it doesn't sound good to me?

Alec

[Raider]

If you are right that means dropping the gearbox which is nit a favourite past time on axle stands on my drive :-/

Still better than a problem out on the road tho

[Andy Flexney]

Martin,

up your way today and just got back.

It sound like the taper pin to me especially as you say it went all of a sudden and no loss of hydraulic oil.

According to the CT un-written law the best place to change a clutch or repair a gearbox is on a small country road in France or a Dutch car park. I would  suggest you book a few days holiday and take the car to the continent.

AndyF

[Raider]

Isn't that usually on a CT event though?

It is quite a while yo wait until nect years 10cr although the Dutch CT event in the Autumn could be an option ;D

[thescrapman]

Martin

The advantage of doing it during an event is all the "encouragement" you will get from passing cars.

On another note, possibly depressing, are the thrust washers in the sump?

Pressing the clutch and stalling the engine is a sign of that.

Cheers

Colin

[Raider]

Bloody well hope the thrust washers are not in the sump as I have just finished rebuilding the engine! !

[Raider]

AndyF wrote:

Martin,

It sound like the taper pin to me especially as you say it went all of a sudden and no loss of hydraulic oil.

AndyF

Taper pin? Been looking at the parts catalogue and there's a clevis pin external to the gearbox from the pushrod  to the clutch actuating arm. Do you mean this? If so that's not so bad.

[Raider]

Only just checked and the fluid level is low so I may be lucky.

Now to find a garage that actually sells stuff for cars on a bank holiday

[piman]

Hello Martin,

I'm afraid not, its inside the bell housing, a tapered screw that goes into the fork and picks up on the cross shaft. If it's broken you need to check the hole in the cross shaft with a new screw, it should be a nice snug fit over the whole length, Lapping the pin to the shaft is a good idea. Also ensure the head of the screw doesn't bottom when it's finally tight, if so it won't last long.

Alec

[Raider]

Well putting fluid in and bleeding the system has not helped. Actually gear selection is getting worse.  More investigation needed another day!

I have a horrible feeling you are right Alec

Still, the engine sounds lovely :)

[Raider]

Colin, I got Deana to press the clutch and the front pulley never moved one bit so I don't think there's a problem with the thrust washers.

Alec - take a look at the photo. Seems to me this is less than 90 degrees and so you are probably right.

[piman]

Hello Martin,

looks like it; in general, mechanically, the principle is that with any lever, the lever and actuator are at 90 degrees with half travel, this gives maximum mechanical advantage, in other words at rest  the angle is greater than 90 degrees and at full travel less than 90 degrees by the same difference. This is the theoretical ideal.

Alec

[esxefi]

if it is the taper pin don't put another one in.

get the shaft and fork machined and tapped for a 10mm allen bolt and secure with locking wire....it wont fail.

[Raider]

I parked up the 2000 and walked away basically.

Then yesterday I noticed a stain on the drive from the area of the slave cylinder. I checked the clutch master cylinder and there's no fluid in it.

I am not quite sure what's going on here but one thing for sure is this isn't helping!

[Richard B]

Could be a small hole in the flexible plastic pipe?

[Spitfire2500]

Richard_B wrote:

Could be a small hole in the flexible plastic pipe?

I'm wondering if it's leaking out of the slave - badly worn seals and/or piston or bleed nipple not fully tightened causing it to gravity bleed itself. Would also the explain the poor clutch engagement.

[Raider]

I have a new braided hose in place of the original plastic pipe so I don't think that's the problem.

It could well be the seals in the slave  cylinder as the car was off the road for more than 2 years.

I should really get under the car and see if I can track down where the leak is.

[dazzer]

As I said originally its either the lockheed master or the slave or both. Also check the slave is on the correct side of the bell housing. Once you get it right it'll be no problem again for a long time. Mine would work perfectly for months and then suddenly stop working and then miraculously start working again. Eventually I just replaced the slave for a second time and rebuilt the master. Although I also purchased a generic master from Demon tweeks as a back up but never got to fit it as all well several rallies later.

[Raider]

Well today I fitted a brand new slave cylinder but it hasn't helped.

As I decided to finish for the day I spotted that as I put my foot on the clutch there was a spray of clutch fluid from the braided hose where it fits to the master cylinder - fluid can be seen where the brass washer is.

Now, should there be a washer there at all I wonder? Looking at old photos of the under bonnet area it doesn't look like there was one ther before with the old hose.