why does my brake pedal go all the way down?

[pimplogic]

my brake pedal goes all the way to the floor before the wheels lock up. sometimes it wont even lock. i just replaced the master cyl and it slill wont lock my dad says it may be the power brake booster. help plz

 

[beermonkey9417]

if it was the power booster youd have a hard pedal like a manual brake. was the master cylinder you bought referbished? if so then theres yer prob, buy a NEW master cylinder and make sure you flush the system in the proper sequence. for some reason when i bought a referbished M.C. it had a squishy pedal, so now i have to get a new one installed.

 

[FE3X CLONE]

Did you bench bleed the master cylinder? Did you bleed all of your brakes? Starting with the rear passenger, then rear driver then front passenger then front driver?

 

[pimplogic]

the master cyl was new i bled the master cyl still no go. i bled the brakes. but i dont have rears hooked up because they dont work. still this is bs.

 

[FE3X CLONE]

What do you mean you don't have the rears hooked up?

First off, FIX THE REARS! You know those don't work, so I would have started there before messing with the MC.

What did you do with the brake lines in the rear? It sounds like you have a ton of air in the system.

 

[pimplogic]

the master cyl is pluggeed for the rears. i broke the bolts to the rear in the summer time so i disconnected them thats beyond the point. the car braked fine up until a week ago. i checked the pads theyre good but when my uncle steps on the brakes the calipers dont move. so is the calipers freezing a common problem for these cars?

 

[Bonnewagon]

You're driving around on just the fronts? WOWSERS! You must like living dangerously. OK. First off, park it, and fix the rear brakes. Then start at the master and bench bleed it until NO bubbles show. If you don't know how-get someone who does. Then bleed all 4 wheels starting at the farthest and ending at the nearest the MC. Have a helper keep the MC topped off with fluid so no air can sneek in. With the motor off, you should have a good hard pedal, if not, start over and rebleed everything until you do. If it slowly drops you have a leak, fix it. If no leak, you may have a bum MC with an internal leak. When you have a good hard pedal, start the motor and see if the pedal is still hard. It will drop a tiny bit at first, but will be solid. If not, and it slowly drops to the floor, you need a new booster. This is the ONLY way to test the booster, all the brakes must be operational and no leaks anywhere. Above all, realise the brakes are the most important part of a car- don't take shortcuts, be safe.

 

[carmangary]

Sounds like air in the system to me. I put a new MC on my Cutlass this past summer and it took a lot of bleeding to get all of the air out.

 

[Doober]

Blocking the flow to the rear at the master cylinder?

No wonder you're having a problem. You probably ruined the m/c by doing so. What bolts are you talking about breaking off? You need all 4 brakes to be working properly to be able to stop properly... they don't put brakes on all 4 wheels just for the heck of it.

:lol: at calling it BS by the way, you made a severely improper change to the system instead of fixing what should've been repaired properly to start with.

 

[mickey-d]

Yo Blake442, you see what I mean about this guys posts?? How do you help some one like that?? I'm more than willing to help, been doing automotive(car and truck)for over 40yrs. 🙂 The problem here is that the guy is either really out there, or he has no clue !! I think we would have better luck getting a dog to lay an egg, but I'm willing to try if YOU can figure out HOW ! :lol: ...................mickey-d :?