Brake pedal - braking fault

[newuserhere]

What are your thoughts....

Brake pedal has a lot of travel to floor before biting. If I pump three or four times it starts braking a lot higher and feels normal. Within seconds though back to how it was before..
It's like this stationary and driving with engine running.
Pedals rock solid when engine off and stationary.

[S0 What]

What car it is might help? rear drums or discs ??
drums, shoes probably need adjusting
rear discs, has it had new rear pads recently? if yes ther piston locating notch might not have been linned up with the pin on the pad.
Could be a slack wheel bearing causing pad knock off, could be air in the system or it could be a known issue with that particular model (whatever it is)

[newuserhere]

1.2 clio
Drums

[AndySpecC]

Sounds exactly the same as what is happening on my civic. My Internetting suggests it's the master cylinder but I'm waiting for one to turn up so can't tell you if that fixes it.

[newuserhere]

I would have though master cylinder would cause a soft pedal when pressed all the time

[AndySpecC]

From what I've read a soft pedal problem is a master cylinder fault and a hard pedal problem I'd a servo fault.

[newuserhere]

If seals in master cylinder were letting fluid back you'd see fluid passing back at all times so pedal would sink

[newuserhere]

I think tbh my problem will be rear brake cylinders seeping out but was wondering what others thought

[AndySpecC]

If you had a leak big enough to make the pedal drop I'd have thought you'd notice the fluid level dropping pretty quickly?

[AndySpecC]

If you can clamp off the rear hoses and see if the problem is still there you could eliminate that one way or the other?

[S0 What]

Drums i'd check the adjustment of the N/S shoes, no idea why but it's usually the N/S that backs off or refuses to adjust for wear, IMHO it's down to the adjusters not liking the way the shoes shift under braking, they should be reversed on the N/S but rarely are, i very rarely see O/S adjustment issues on drum braked cars, both my pug 106s suffer N/S adjustment issues, i have to manualy adjust them every few months and the whole lot is new, new drums, fitting kit, shoes, cylinders and adjusters ?
If you pull the handbrake up a few clicks (so it's not on or dragging) does the pedal firm up? if yes check the adjustment