Brake pedal going to floor....help
Thread Starter
2nd Gear
Joined: May 2003
Posts: 2
Likes: 0
From: PUYALLUP WA
Brake pedal going to floor....help
I have an 85 Vette Coupe and when I'm at a stop light or have to apply the brakes for along period of time, the brake pedal slowly goes to to floor and I have to pump the pedal to get pressure back again. Normal stopping is fine, just long brake pressure applications. What do I need to fix. There is no leakage anywhere, I put in new brake fluid about six months ago, calipers are fine. Do you think my master cylinder needs to be replaced or rebuilt? Please help. E-Mail me at: don.curnow@wa.ngb.army.mil
Thanks guys (and gals),
DON :(
Thanks guys (and gals),
DON :(
Instructor
Joined: Oct 2002
Posts: 135
Likes: 0
From: Pitman NJ
Re: Brake pedal going to floor....help (dolphinlovr)
I hate to say it but it does sound like your master cylinder is bad. With the cap off very SLOWLY pump you brakes and check to see if there are air bubbles coming out of the bottom of the master cylinder. That's one tell tail sign that the master cylinder either needs to be bled or it's sucking air causing a spongy pedal. Good luck.
Le Mans Master
Joined: Jan 2000
Posts: 6,377
Likes: 21
From: Traverse City MI
Re: Brake pedal going to floor....help (dolphinlovr)
I am not a brake expert, but I would look at your master. It sounds like it's not holding the pressure well. You should be able to pull it off the car and take it apart and inspect the seals. You will probably need a ring puller to get inside the master.
Racer
Joined: Jul 2002
Posts: 447
Likes: 0
From: Malta Europe
Re: Brake pedal going to floor....help (Aaron71771)
On my 88 I had the same brake problems !!! I changed the master cylinder and still the problem was there :skep: Then I bleded the hack out of em so I will make shure that there is no air traped in the system but still the problem was there , Than I flushed the whole system with heavy duty DOT 4 brake fluid and what do you know , the brake pedal went solid rock and the brakes was very firm and responding :thumbs:
Race Director
Joined: Mar 1999
Posts: 16,950
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From: Stafford, Virginia Kittah, Kittah, Kittah...
Re: Brake pedal going to floor....help (dolphinlovr)
Sounds like the master cylinder to me...
Be very careful and I wouldn't drive it if I were you... It could fail anytime now from a couple of weeks to the next time you drive it...
I had that condition happen in my 88 IROC a long time ago... I went from a spongy brake pedal at one stoplight before my home to nearly hitting the garage wall when I pulled it into the driveway... If it wasn't for the e-brake I would have creamed both the car and the wall... :eek:
Another word of advice... Stay away from the reman chain store replacements... It end up costing me more since the replacement failed about 3 months aftrer I installed it also... I was told it had to do with it being bored out and oversized seals used... Not a good fix...
If it was simply air in the lines the pedal would feel spongy all the time rather than just when you're on it for awhile...
Be very careful and I wouldn't drive it if I were you... It could fail anytime now from a couple of weeks to the next time you drive it...
I had that condition happen in my 88 IROC a long time ago... I went from a spongy brake pedal at one stoplight before my home to nearly hitting the garage wall when I pulled it into the driveway... If it wasn't for the e-brake I would have creamed both the car and the wall... :eek:
Another word of advice... Stay away from the reman chain store replacements... It end up costing me more since the replacement failed about 3 months aftrer I installed it also... I was told it had to do with it being bored out and oversized seals used... Not a good fix...
If it was simply air in the lines the pedal would feel spongy all the time rather than just when you're on it for awhile...
