I am just about to my wits end with this problem.

I just got done doing a 5 Speed Conversion and for the most part things went well. I decided to change my Pads, Rotors, Brake Fluid and add SS Brake Lines while I was at it.

I Bled the system properly, but when all was said and done the pedal sinks to the floor. So I think it may be the Brake Booster as it was making a funny sound, I had a spare and swapped it out. Still no luck even after re-bleeding the brakes.

So I purchase a new brake master cylinder and do a quick bench bleed and proceed to install and re-bleed the system. Now the pedal does not sink to the floor, nor does not make any "funny noises". However upon going to test drive the car I noticed that when the pedal is applied there are NO Brakes, however there is pressure in the pedal. I must use the E-brake to stop.

There are no leaks, at any of the four corners nor from the Brake Master Cylinder. I am sure I bled the brakes properly and even took extra precautions in doing so.

I am so frusturated.

Even though I bled that master cylinder if it wasn't done text book would it cause these problems?

Please Help!!

Thanks!

P.S. This is a NON-ABS Car.

 

Sounds like the booster you swapped in might be bad,but you should try bench bleeding the m/c exactly per instructions first..

Also,i recommend getting a pressure/vacuum bleeder from your local auto parts store..They save much time and seem to do a better job fully bleeding the brake system of air...

 

Very true. I changed my rotors and pads and bled the brakes at least 6 or 7 times while I was trying to figure out why the brakes were so spongy and weak. Finally I bought a $30 pump vacuum bleeder kit at autozone and did it instead of manually doing it, and it worked perfectly after the first bleed! To this day I have no idea what we were doing wrong when we were manually bleeding the brakes, but the vacuum pump bleeder kit worked perfectly.

 

Your problem is that you didn't get all the air out after you changed the lines and fluid. Swapping other components did nothing to address the issue, only wasted your time.

You need to run a lot of fluid through the system in order to bleed out all the air after changing lines and/or the master cylinder. A vacuum bleeder will help you if your doing the job alone. Pull up to 1/2 qt. through each caliper. Make sure the last burst of fluid through each caliper is done under pressure - foot on the brake, open the bleeder and push the pedal down to the floor then close the bleeder while the brake pedal is down.

 

One would think that there must still be air in the lines however, I know that I have pulled all the air out and I have ran much more fluid then that through each caliper. I also used ATE Blue which helps indicated old fluid from the new fluid.

I have bled the system 15+ times. I have now also properly bled the M/C with no improvments. I have also tried using a vacuum pump to bleed the brake lines and that also did not seem to help.

 

Just a shot in the dark... happened to a buddy recently whiel he wasn't paying attention..

You did have someone filling the m/c 'while' you did the bleeding right?

My buddy couldn't figure out why there was still air in the system after bleeding it 5 times. Common sense thing, but he wasn't thinking.

 

Yes, the M/C was never ran dry and the one time we did we re-bled the entire system.

 

You still have air in the system somewhere...

 

Speedcrazie, Have you made any progress with the spongy pedal? I am having the same problem.
My problem started with a low pedal. After inspection the left front caliper was hanging up, replaced caliper. Bled system, only to find the brake pedal is spongy. So, replaced the MC, and still the same problem. Had car towed to the dealer, they inspected and bled the system.
The dealer rec. replacing the MC for $450 little steep for my pockets. So I had the car towed to my house, returned the new master as a defect, and installed the 2nd new MC (with in 2 weeks). Bled brakes and still the same problem, going to try the vacuum bleeder.

2000 Nissam Maxima SE 5 speed