I'm fairly certain it's the master cylinder gone, but just wanted to double check the symptoms are correct? if I put my foot hard on the breaks there is a little resistance but not for long, but keeping foot hard down it doesn't quite reach the floor. if I pit my foot very lightly on the pedal, it sinks right down to the floor.

am I right in thinking this is master cylinder? I've bled brakes, no air in system, no leaks, fluid new and full.
the only other thing I could imagine is servo but not sure what tests I can do to rule one out/confirm the other?

no abs involved, it's a 98 punto 1.1

 

has this happend before or after bleading your brakes?

 

If the servo had packed up the pedal would be very heavy.

 

before bleeding.

 

Did you do any work on the braking system before this happened? Sounds like master cylinder to me. I never push brake pedal all the way to the floor when bleeding brakes, only about half way, some cars dont like it and it damages the seals.

 

Master cylinder would be first on the list as you'd get a very hard pedal with no servo

 

had this on my pedal box, was MC

 

Only usually when the master cylinder is damaged/worn. IMO it needs changing then anyway.

 

Master cylinder is fooked, they have two, maybe 3 sets of seals on them just incase the first let go,you then have the 2nd set to catch the fluid, i think this is why you are feeling resistance, then fades away.

If you have no visable leaks then id def change the master cylinder.

 

to be double sure clamp all 4 brake hoses and see if the pedal goes normal, if it does take 1 clamp off at a time checking pedal after each, if pedal becomes crap again then the problem lies on the corner you unclamped last

If the pedal is still crap with all hoses clamped off then its the master cylinder

 

nice one, cheers all!