Clutch drops to floor / no pressure

[blinkme323]

Hey everyone,

About a month ago I had an issue where I lost all pressure in the clutch pedal of my Civic. We found that the master cylinder reservoir was bone dry, but being that it was old, decided to replace it and the slave instead of just re-filling it. That immediately corrected the issue and the car drove perfectly for about a month.

However, over the last few days, I slowly felt the clutch losing more and more pressure, until finally it had none again. The interesting thing this time, is that the reservoir is still filled to the top. Also, if I pump the clutch a number of times by hand, it eventually starts to build more pressure. This also happened to coincide with some extreme cold, so I'm not sure if there is any correlation there.

Do you guys have any ideas on what the problem could be? I'm not seeing any noticeable leaks coming from anywhere, so I'm kind of at a loss.

Thanks!

 

[XpL0d3r]

I'd inspect your clutch lines or leaks, and bleed the system of any excess air if you haven't done so already.

 

[HeX]

I'd inspect your clutch lines or leaks, and bleed the system of any excess air if you haven't done so already.

I agree. I had a leak from my slave recently and did some research. I recall reading somewhere that the drop in temp can affect any slight moisture in the lines. That could lead to an added creation of air in the line which could be your case. Air bleed the system thoroughly & make sure you're using DOT3 or DOT4 brake fluid. I personally used synthetic fluid.

 

[blinkme323]

I'd inspect your clutch lines or leaks, and bleed the system of any excess air if you haven't done so already.

I just bled the system again and that seems to have done the trick (for now). Thanks for the advice!

 

[XpL0d3r]

I just bled the system again and that seems to have done the trick (for now). Thanks for the advice!

No problem! If the clutch seems to get soft again you most likely have a small leak somewhere.