10 replies to this topic

[Spiffingly Good]

Model: Clubman 1098cc
Year: 1978
Description of problem (please be as in depth as possible):

Little problem after finally putting the engine back into my project and starting her up, the clutch doesn't fully disengage.

Car has a rebuilt clutch master cylinder, new slave cylinder and has been set up correctly(so I believe), The arm is traveling to it's maximum extent, with the slave cylinder on the verge of popping out it's piston.

I can just about get into second gear with the engine running and the brakes applied, there's not enough to get into first.

So my question is, what would be the first thing to check, I'm figuring mechanical, clutch seized or I've put something together wrong internally.

All ideas welcome.

[Neildanks]

Model: Clubman 1098cc
Year: 1978
Description of problem (please be as in depth as possible):

Little problem after finally putting the engine back into my project and starting her up, the clutch doesn't fully disengage.

Car has a rebuilt clutch master cylinder, new slave cylinder and has been set up correctly(so I believe), The arm is traveling to it's maximum extent, with the slave cylinder on the verge of popping out it's piston.

I can just about get into second gear with the engine running and the brakes applied, there's not enough to get into first.

So my question is, what would be the first thing to check, I'm figuring mechanical, clutch seized or I've put something together wrong internally.

All ideas welcome.

I had a similar problem turned out to be the slave cylinder support bolt what connects from the casing to the bracket if this helps
The bracket was moving and not letting the rod move the clutch all the way

[MRA]

TRY ME click here....

[Spiffingly Good]

TRY ME click here....

I shall give that a go once I have chance, the symptoms sound about right so hopefully that will be the problem.

[bmcecosse]

If it's a pre-verto clutch - set the gap to the little stop bolt down to 15 thou. It was also quite common to have to bend the arm inwards towards the slave cylinder - or to lengthen the push rod that enters the slave cylinder. I'm assuming of course that you have bled all the air out of the hydraulics........

[MRA]

Unfortunately the old tricks were nothing but tricks or bodges that didn't often work that well, bending the arm just moves the ball to a different position however in reality it also changes its arc of movement, thus allowing for less movement.....

As does extending the pushrod, there really is only one way to get the job done correctly and also get some reliability back in to the Classic Mini and that is to do the job properely first time.... not second, third or fourth

If these bodges were outlawed more people would be able to benefit from actually driving their Minis

[Spiffingly Good]

Well today I finally got time to check this problem out. The problem was me I hadnt tightened the Large crankshaft Nut hence it had unwound itself and prevented me from pressing the clutch.
I'm such a tool sometimes

[jonny d]

crankshaft nut?

[Cooperman]

Here, again, is a fault analysis of the causes of clutch drag:

CLUTCH DRAG

Clutch drag or failure to disengage is not an uncommon problem with the Mini.
There are several possible causes as follows:
A. HYDRAULIC SYSTEM
1. Wear in the pedal spindle or failure of the pedal to master cylinder clevis pin.
2. Failure of seals in the clutch master cylinder.
3. ‘Ballooning’ of flexible hose due to internal hose degradation or damage
4. Air in system due to inadequate bleeding
5. Failure of slave cylinder seals

B. MECHANICAL SYSTEM – WITHDRAWAL MECHANISM
1. Wear in top clevis pin
2. Wear in lower clevis pin
3. Bent arm
4. Worn or broken ball at lower end of arm where it engages into plunger.
5. Wear in plunger ball seat.
6. Incorrect setting of overthrow stop nuts
7. Incorrect setting of adjusting screw
8. Corrosion between plunger and clutch cover due to lack of lubrication.
9. Thrust bearing failure – accompanied by a lot of noise.

C. THE CLUTCH ASSEMBLY
1. Failure of clutch diaphragm spring due to fatigue or distortion
2. Centre plate hub not sliding on primary gear splines.
3. Clutch plate surface de-laminating or breaking up
4. Distorted clutch plate.
5. I fitted, clutch plate shock springs broken and causing a ‘jam’.
6. Primary gear not rotating freely on crankshaft due to either: i) Insufficient primary gear end float, ii) Primary gear bushes seizing on crankshaft, or iii) Primary gear bushes breaking up

[jamiestevenbell]

ok well are you on about the nut/bolt on the end of the flywheel casing? If so does any one know how tight this should be

[Spiffingly Good]

Yes I meant the flywheel nut. I did mine upto 150Nm a Haynes said.