Zero (0) Brake Pedal after Brake Servicing on my '04 WRX

[LaszloT]

Following a routine Spring brake servicing, there is NO brake pedal pressure at all. It just sinks to the floor when depressed. Now I'm depressed. Ha ha.

Investigation showed that the master cylinder just stopped pushing brake fluid when pressing the brake pedal, which is unexpected and not good.

Can the master cylinder piston shaft somehow get disconnected from the piston for any reason?

http://i.imgur.com/xy4aTWc.jpg

Summer 2013 we upgraded the fluid to Motul 600, but that's the only thing done to the brake plumbing since the Rex was acquired in Mar 2013.

http://i.imgur.com/xp5u1J2.jpg

[dubya_rx]

Pumping doesn't bring it back I assume.

[LaszloT]

Pedal actuator port had some decay. No pedal action would change it, and Caveman tried bleeding and even drawing the fluid from the lines. The master cylinder just wasn't pushing any fluid at all.

We started to suspect a mechanical linkage connection, and this is what we found when the master cylinder was changed.

http://i.imgur.com/G2O2fSz.jpg

[Cavemanrjc]

The master had disgustingly dirty fluid, with a substantial amounts of particulate matter in in. Without fully dismantling the unit I can only suspect a ripped seal but I could allso see a plugged transfer port not allowing fluid to refill the ports in the piston. Either way the repair is the same. Master replacement, as rebuilding is not economicly feasible when a replacemant is only $165

New master bench bleed and installed, full system flush and all is good in the world. Great peddel feel now.

[Cavemanrjc]

And hey, what means "we"? Lol

[LaszloT]

New master bench bleed and installed, full system flush and all is good in the world. Great peddel feel now.

Delighted to find the issue in the shop, rather than at speed. Drives like new now. :)

Thanks Caveman,

[STeveD]

And hey, what means "we"? Lol

We guys who create the problem through lack of maintenance and then fund it's repair like to feel we're part of the process, too.