Soft brake pedal

[Rod1883]

As per the title - if I press the brake pedal gently it feels soft and travels a long way, for example in the situation of braking very gently coming to a junction.
If I press the pedal hard, the pedal is good and firm and doesn't drift downwards. I've bled the brakes through with new fluid in case it was an effect of old fluid, but it hasn't improved things in this respect.
Can anyone comment on what the issue might be?
Thanks

[Lingen]

Rod. One of the seals is failing in the master cylinder. They can be replaced, but as new cylinders are reasonably priced I would reccommend taking that route to avoid it happening again in a year or two.
Mike.

[Rod1883]

Thanks Mike. I have ordered another Master as I wondered about that being the cause myself - it's due tomorrow.
Another quick question - is it possible to change the master without removing the servo as the car is a manual and I understand that the clutch master gets in the way of removing the servo.
Any other tips and hints for replacing the master would be gratefully received.

[Lingen]

Rod.
The master cylinder can easily be removed without the servo.
Pump the brake pedal a few times first to remove any vacuum from the servo, as this can "Hang on" to the master cylinder. Drain the reservoir.
Then undo the brake pipes. I always put something under them to keep any fluid spillage off the paint, ease them out of the cylinder, and bend them up out of the way.
Then just remove the two nuts and pull/wiggle the cylinder off the servo.
Fitting the new cylinder;
There is a correct clearance between the end of the rod in the servo, and the piston in the cylinder, the end of the rod being adjustable to obtain it.
I suggest you measure the distance from the back of the piston to the end of the master cylinder casting on your old unit, and compare it with the new one. With a bit of luck they will both be near enough the same. If not, you should alter the length of the pushrod to account for the difference..
Then refit the cylinder and the pipes. You will find a good deal of pedal pumping may be necessary to prime the cylinder and get it working. Then you will have to bleed all the brakes and perhaps re-set the PDW switch.
I know a short cut to that part which you might like to phone/Email me about!
Mike..

[NeilR]

Stopping the PDW switch moving is easy, just unscrew the switch & replace with a bolt with a 45degree taper on the end, lightly nipped up only !.
Can't remember what thread it is at the mo, but easy enough to find out when the switch is removed.

[sujitroy]

here a video I made. with bolt size needed.
https://youtu.be/NwchxJ3_p9U?si=4DvhrEJb-uLOuam_

[Rod1883]

Well the Master cylinder was the issue - or at least replacing it today seems to have solved the problem.
Thanks for all the help and advice.