[The definitive Gearbox thread]

Thank you @ObjectiveAway , @Rick !

The gearbox was removed due to the failure.
Clutch has become super hard and hammered into gearbox by torsion shocks while clutching. 
Gearbox has become solid, concreted.
So sorry, only 5th swap is not possible.

Calculating the final ratio of:

ESY 5th gear 3,65 (4.06 * 0,9)

with

ETD 4th gear 3,87 (3,87 * 0,93)

and they are quite similar revs

and there is room for 
5th gear 2,86 (3,87 * 0,74)

There are 190 mm and 200 mm diameter clutch
versions of 085 gearbox. 
Are they different - not compatible? 
(I have 190mm clutch)

I consider DHB, DKF, DQW, DXP, ERD, ETD, FGF

[The definitive Gearbox thread]

I want to swap the gearbox to the different gear ratio.
Are the shifters of type A and B interchangable or not?
(if there are differences in the dimensions of the gearshift rod?)

I have ESY gearbox and it makes the car very revvy and not enough speed at the top gear.

[What is Clutch disengage force ?]

mk2 you wrote:
 

Quote

But what I'd noticed is that the primary input shaft seal, which is meant to keep the gear oil inside the gearbox, starts to weep very slightly as it gets old. The rotary action of the spinning shaft or maybe just capilary action allows a very small amount of oil to build up around the guide sleeve. Some of that oil makes its way between the sleeve and the releaser which naturally starts to collect clutch dust. Which then turns into really thick sticky gunge.

The gunge has properties best described as very thick sticky toffee like tar, with fine grit in. Such a high viscosity substance between the sleeve and releaser simply jams the action, resulting in a heavy clutch. It doesn't help that the clutch release bearing lever that presses against the springs moves in an arc, which naturally tries to twist the release bearing when you put your foot on it. When you release, it gets pushed straight back by the springs, so engaging is not a problem- only releasing...

so my guess is that fine metal in your gearbox oil has worn the seal, which is weeping, collecting dust and causing the releaser to be sticky. 

 

 

[What is Clutch disengage force ?]

mk2
Thank you for your answer and recognition! 
I am an egineer, maybe for that reason the method is little more than guessing.

I guess the additional friction resistance of the spline slider made the clutching work of the cluch 
literally "explosion of torque" from the rotation inertion due to the different rotation velocities:
of engine and gearbox spline axle. The clutch is not worn out, because the clutching was done in 
small parts of a second so this was a easy task. 
But for the gearbox it was not.

The kicking violently the gearwheels made them first weakend, then dead.

Now I have dead gearbox, not spinning the axle in some gear positions. 
Concrete stop. As concrete poured into and dried.

 

My consideration is to exchange the gearbox (with one with other gear ratio to move faster)
and to have a clutch assembly
so healthy
to not to spoil that newly exchanged gearbox again.

Now I have no clue if my cluthch - although "normal" is healthy?

 

[What is Clutch disengage force ?]

mk2
Thank you for your answer!

I have read something about that glutous mixture here somewhere here in the topic of clutch... 

The conclusion seems to be correct: the mixture clogs the splinter axle. 
I understand this.

Having read about these symptoms I tried to check the cover plate with the spring.
It is outside the working environment and engaged by the lever. 
No bearing and no splinter axle resistance.

On the polish fb mechanics group they told me that proper force is 100 till 140 kg.
Mine is in the normal range.

>A new clutch needs about 200N (~20kg) of force to operate at the pedal.

YT mechanic measured 24 lb (12, 5 kg) at the pedal. 

I had so much more than 12-20 kg at the pedal!

(I have driven several cars, and this one had the hardest clutch. Easily 40kg.)

Do you think that this failure is due to the strong force on the spring + friction force? 

My dillema: if clutch cover functions within the range - should I change it? 
Will I get the easier, lighter new cluthch cover? (I doubt it).

I attach pictures from checking the clutch cover force.
The lever presses the clutch, reaching 100 kg easily., 
maitaining disengaged at 80 kg.

[What is Clutch disengage force ?]

I have a question.

I had the problems with the clutch diseengaging,
due to the very hard clutch pedal.
And it "bumped" harshly.
No way to soft clutching, shooting the clutch all the time.

Gearbox has expired and needs replacement.. ;-(

What should be the force direct to the diaphragm spring to disengage clutch? 
I mean the immediate force from the bearing pushing the fingers'-spring.

I have disassembled my VW 1.0 ltr motor clutch, 190mm diam. from Lupo.
Clutch plate not worn, flywheel dry and free from overheating.
Bearing was not heard while disengaging. 
(the worn-out gearbox was heard while clutch engaged)

I have measured this disengaging force with scale 
pushing to the center of the preasure plate
(diaphragm spring) with a lever.

and it came 100 kg to disengage (1000 N newtons)
it is huge force!
Maintaining disengaed took 80 kg
ad releasing begins at 60 kg

I know this is not other parts that made so much resistance, it is a clutch spring.

I wonder is this a normal pressure force, this 100kg? 
Certainly not.
What is the source of this spring stiffness? Overheating?