Join Date: Dec 2013
Nominated 27 Times in 25 Posts
TOTW/F/M Award(s): 8
Thanked 1,794 Times in 1,373 Posts
Re: Sinking Pedal - Brake Bleeding
I too would be interested.
I have come across pressure sensitive non returns in the line from a master cylinder... designed to keep some pressure in the system and stop drum brakes retracting too far.
And non return dampers, in the output ports, check valve with a hole in them to allow full flow in one direction and limited on return.
Similar into the reservoir to stop master cylinder full pressure squirting into the reservoir.
And can see that failures of these could give excessive travel before the brakes bite.
But not the sinking feeling that the OP describes.
But always willing to learn.
Currently in Dancingdad's garage:
Qashqai 1.6 spark driven, Kia Sedona 2.9 TDI, Scenic II 15DCi 2004 (SORN) not quite RIP.