brake feels like its loosing pressure?

[phil-r]

every time i hit the brakes it stops the car fine but if i keep my foot on the brakes it seems to loose pressure so to say, is it supposed to do this or am i in some sort of trouble?

[SPADGE]

Dodgy master cylinder or air in the system

[fuzzy]

has it lost any fluid?

[Brianmoooore]

has it lost any fluid?

External leaks tend be be quite fast and definite. This is probably just fluid leaking past the main seal in the m/cylinder. Replacement, and a good flush of the brake fluid is the only cure!

[phil-r]

so what i have to replace the m/chead?

[SPADGE]

so what i have to replace the m/chead?

Unless you have had recent brake work done that required the system to be bled and this wasn't done correctly then yes the brake master cylinder will need replacing.

[abelai]

Could the flexi hoses cause this?

[phil-r]

i know that the cap for the brake fluid bottle is a little cracked but not really leaking, any remote chance it could be that?

[abelai]

no

[SPADGE]

i know that the cap for the brake fluid bottle is a little cracked but not really leaking, any remote chance it could be that?

No but it could be the reason why the master has failed.
The brake fluid is under no pressure in the bottle so a leaking cap will have no bearing on the pressure issue.
Dirt and grit could have got in via this crack however and killed the seals in the master.

[Brianmoooore]

i know that the cap for the brake fluid bottle is a little cracked

Are you sure you're not confusing the brake fluid resevoir with the clutch fluid resevoir?

[SPADGE]

i know that the cap for the brake fluid bottle is a little cracked

Are you sure you're not confusing the brake fluid resevoir with the clutch fluid resevoir?

Good point Brian!
I've never seen a cracked brake fluid res cap but plenty of clutch ones that have been tightened a 'little' too much.

[phil-r]

no, the brake ones cap has a little measureing stick, if the cluch one is cracked, will that make a difference to my cluch at all?

[Gunni]

master cylinder is dead and needs replacing.
if you stand on the pedal hard it doesn´t go down does it?
but when you don´t push to hard is eases down.

That´s a dead master.

[phil-r]

GREAT!!!
Thanks a whole bunch guys i really do appreciate your help.
now to go and scratch for all mu penny's to fix this.

its a tough job right, one a pro should rather tend to?