yesterday after some firm braking my pedal went to the floor...

it now only brakes as the pedal is about 2-3 cm from the floor, and then only the front right and left rear brakes. looked under the car expecting a leak (where it would loose pressure, leak and only brake on the opposing diagonal brakes)

checked all the lines and cilinders for leakage, nothing. after 3 trips with regular braking the oil level has not declined.

cranked up the front left wheel and told my mate to put the pedal to the floor. the wheel stopped spinning, but while he still has the pedal floored you can turn the wheel again with no effort. it only seems to brake at initial pressure, but then the pedal drops to the floor and only 2 wheels brake. cranked up right rear wheel (drums) and pulled of the drum. then saw a visual representation of what happened up front. the cilinder pops out at initial braking but returns back in while still holding the pedal on the floor.

noticed the same when driving again, if i touch the pedal briefly it brakes even but short, if i pump it shallow it brakes straight, but if i just brake pedal goes to the floor and it pulls right instantly.

never seen this before! can you guys help me???

this car of mine brake dangerously and i need it everyday (87 civic), no time to pull the whole brake system and diagnose. someone had this ever happen, or can phantom what the &%^$%(4 is wrong?

 

Sounds like the seals in your master cylinder have gone out. You mentioned it first started after some firm braking. During regular use the master cylinder only covers a small range of travel. Hard braking could have exceeded this normal range and pushed the seals over built up gunk in the master cylinder bore. It happens a lot when people try to bleed their brakes on an old master cylinder.
There is a good writeup here:
http://www.tegger.com/hondafaq/maste...ace/index.html
Take a look and see if it sounds like the issue you are having.

 

thnx man, sounds a lot like and seems very logical

strange it still brakes the last few cm's tough...
have to find me a new BMC

lucky enough some knowledgable people are here, i was flabbergasted.
engines are my home, brake problems is something else

 

Yeah, when my MC went out it would still brake during the last part of travel. You sometimes had to pump the pedal to keep from rolling back on a hill.
I'm not sure what auto part stores you have available where you live but I've always used remanufactured master cylinders from local auto part stores like Autozone and Advance and never had any issues. I'm sure I'll get flamed for recommending something other than OEM parts, but with a lifetime warranty the remanufactured ones are hard to pass up.

 

THNX ALOT!!

you've been a great help!
instead of a new one (280$) or a remanufactured one (don't have those around here) or a revision set (80$) i remembered i had my bmc and brakebooster from my "94 civic replaced by a VTI-unit. meaning i had to have a working 94 bmc lying around somewhere, luckely i found it and luckely my 87 bmc and 94 bmc where identical.

bench bled the 94 like explained on the site you posted and bled the brakes. brakes like new again.

all in all, i just want to thank you for the help and advice!!!

for anyone else that might search this: if you have the feeling you can push right trough your brakes untill the last inch, the car brakes a little upon pushing then 'releases' and only brakes the last inch on maybe not all four wheels. go look for leaks, if you can't find them. its probably your BMC !!!