After driving around for about an hour I did a turn to line up with the driveway to reverse in. But the brake pedal went straight to the floor before the car stopped. I kept pressing the brakes as I went into the driveway and sometimes it worked fine (perhaps not the normal way, just not to the floor) while other times it went to the floor.
I've not done any work on the car for a few weeks, and I've driven ~300 miles without any issues. Saying that...
The last work I did was replacing the springs on the one of the rear drum brakes (the little ones that point outwards) as one had fallen off. This seems to have worked fine so hopefully I didn't break something!
I'm pretty sure ~3 years ago the master cylinder & a slave cylinder was replaced.
What I've checked so far
- Fluid in the reservoir is full
- Holding my foot on the brake with the engine off, the pedal stays in one place
- Having my foot on the brake, turning the engine on, the pedal slowly sinks (not to the floor)
- Turning the engine off and pumping the brakes, it slowly gets harder
- No leaks at the master cylinder by the looks of it
- No leaks around the ABS thing
- I've taken each wheel off and there are no obvious leaks
- I think I found the slave cylinder that was replaced with the master cylinder, but i'm not sure if it's seated correctly? I've looked under the seals and although one looks a little wet, i'm not sure if i'm just seeing things. There's also something white but I don't know what that is. Here's a link to some pictures - https://imgur.com/a/SUf276i
The last thing I can do is bleed the brakes but i'm not sure where the air has come in, and why its occurred suddenly? The heat? If this doesn't work I might have to change the master cylinder..
Any thoughts?