I replaced disc brake pads, rear shoes. wheel cylinder,master cylinder, power brake booster all new. Question: My brake pedal is not solid,goes low to the floor almost. I have bled the master cylinder 1st, then bled furtherest rear to front. I am ready only brake fluid and air bubbles. Yet my brake pedal feels soft maybe sponggy? Engine running or off my pedal is not solid enough? Can you share what might be my problem? I also self adjust rear brakes backing up and no strong results? Can you help? THANKS MaxC
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
Pedal, not peddle. First make sure reservoir is full at the brake master cylinder. Then check your brake pads (for disc brakes) and/or brake shoes (for drum brakes). When the pads or shoes are very worn down, you will get a low pedal. If you have disc brakes on the front and drums on the rear wheels, first try just replacing the front brake pads. If you get a good pedal after the front is done, many people tend to let the rear brake shoes go unless they are making noise. These systems are designed to put most of the braking force on the front discs, so the rear shoes do not need changing as often.
Did you bench bleed the MC before installing it? If not, that's the problem. MUST be bench bled or you'll always have air. If brakes lights are on, the brake switch is out of adjustment OR (since you replaced the MC), the push rod is out of adjustment
check or adjust brake pedal, check brake booster or replace new one, check pedal return spring and bushing, check all wheel cylinder or replace, check brake shoe or brake pad, check brake fluid or replace,.
Not likely that the booster is an issue. The booster would not be able to overcome the brake fluid compression.
First open and inspect all brakes for leaks, adjustment, etc. Check all brake lines.
So if no leaks, did the fluid go low in the MC? If so, pad consumption would eat more than a MC reservoir of fluid, and not require MC replacement, but rebleeding and top up of fluid. If the pads are worn, and you replace them, often this will expel air back through the MC.
If you determine the MC is faulty, bench bleed the new one before install, or you will have lots of problems getting air out....
adjust your rear shoes up so that the rear drums just turn, with them ajusted to a low setting the brake pedal will be low .
also when you start your engine it is noral for the pedal to drop because of the boster ! [ but not to the floor ]
Bruce Pike
The problem is likely either the brake booster which is vacuum powered or the brake master cylinder -- brake booster would be leaking air, master cylinder would be leaking fluid by the O-ring on the piston (internally "leaking by").
This sounds more like a booster failure since the pedal gets soft when engine is started. But probably a good idea to replace both at the same time.
it could be that the master cylinder is bad or the brake booster is bad also check the vacum hose going to the brake booster if it has a hole in it it will lose pressure and make the engine lose rpms
×