It's All About Stopping

          Brakes
      Brakes, the one think on a automobile  you can't do without. Brakes have come a long way since the automobile was invented over 100 years ago. The 1st car's had mechanical brakes. There was no brake fluid, just a bunch of rods hooked to a pedal and ran to the wheels. Even when Henry Ford remodel the Model A to the Model T, it still used mechanical brakes. All the other car manufactures started using hydralic brakes around 1930's. Ford didn't start using hydraulic brakes till around 1938. Hydraulic brakes use a number of different components, master cylinder, wheel cylinders, springs, clips, rubber hoses, metal lines, calipers, drums, rotors and brake fluid. 

    Let's see if I can explain how the brake systems work, so that you may understand it. When you push the brake pedal you are applying pressure to the master cylinder. Your foot is transformed into a super strong pressure machine. That pressure makes anywhere between 500 too 1200 psi. When you add power brakes, that pressure goes up a little. Are you just don't have to push as hard on the pedal. That pressure pushes brake fluid out the master cylinder into the metal lines too the wheels. The front wheels get the full pressure from the master cylinder, the rear wheels get less pressure than the front. The fluid going to the rear goes thru a pressure differentional valve that reduces the pressure. If it didn't go thru the valve the rear tires would lock up. When the fluid reaches the wheels it puts that pressure into wheel cylinders, that expand outward. That outward pressure pushes against the brake shoes, that rub up against a brake drum, slowing the vehicle down to a stop or not. Most all cars today have disc brakes in the front and back. Drum brakes take more maintance than disc brakes. Drum brakes have a lot more moving parts than disc brakes. Where drum brakes pushes the shoes out, disc brakes squeeze a rotor with brake pads thru a brake caliper. To replace drum brakes it takes special tools, It is harder to work on drum brakes than disc brakes. If you have never repaired drum brakes before, never tear both sides down together, you will spend a day trying to fiqure out how to put all those springs, levers, clips back where they go. Leave one side together so you can look at it to put the side you torn down back together. 










    So you are having a braking problem. Let's start with what kind of problem your having. Let's start with the way the pedal feels.


    Hard pedal

    The brake booster may be bad or it may not be getting vacuum. Pull the vacuum hose off booster and feel if it's sucking with engine running. If you have vacuum, you got a bad booster. Unless you have a hydraulic brake system which works off the power steering system. If you have a hard brake pedal with a hydraulic system you probably don't have power steering either.  If you have power steering and a hard pedal, then you have a bad hydra booster.


     Soft pedal or pedal goes to floor 

     This is usually caused by air in the system. May be caused by the rear brakes need to be adjusted or a bad master cylinder. If you pump the pedal a few times and it gets hard, then while you are still pushing down on the pedal. let a little pressure off the pedal while still pushing down a little. And push down again if the pedal goes to the floor, you have a bad master cylinder. Push the emergency pedal down or pull it up, which ever you have, and push brake pedal and see if it is better the first time you hit it. If it is you need to adjust the rear brakes. If it's not you probably have air in the system. How did the  system get air in it. Look in the master cylinder and see if it is low on fluid. If it is start looking for a leak, look behind the master cylinder where it bolts to the brake booster and see if it is wet, under the master cylinder. If it is the master cylinder is leaking. If it is not leaking there, start by looking under the car to see if you see a wet spot along the frame where the brake lines run, check behind the rear wheels and see if it is wet at the bottom of the brake drum. If is leaking behind the wheel, it is a wheel cylinder leaking. A brake system can get air in it thru a wheel cylinder or caliper, by sucking air in. Most of the time if a caliper or cylinder is sucking air it will be damp around it.
 Pulsating pedal   Usually caused by the front disc brake rotors being warped, usually you feel this also in the steering wheel.You can also feel it in the whole car, it will make the car pulsate back and forth.

  Vehicle pulls when you hit the brake pedal

    Depends on which way it pulls, tells you which side is the problem. If it pulls to the right that means the left side is not working. What makes a car pull, usually it is caused by the problem side is not getting brake fluid. It could be caused by a rubber brake hose being glogged. A pinched metal line. Are a froze caliper.


         Brakes in front froze up Are they froze up all the time are just when you drive for awhile. If froze all the time, probably caused by a bad caliper. If freezing up after driving awhile, probably caused by a rubber hose being collasped. Could be a bad caliper, how do you tell which is it. Jack up the side your having problem with. Pump the brake pedal and see if you can spin the tire, if not, break the bleeder on the caliper and see if it frees up. If it stays froze up, you have a bad caliper. If you can spin the tire, pump up the brakes again till the wheel freezes up again. Now move up the brake line to the end of the rubber hose where it hooks up to the metal line. Break the line loose at the fitting, if the wheel stays froze, got a bad brake hose. If the wheel spins, move up the brake line where it hooks up to the differentional valve. Break the line loose between it and the master cylinder and see what happens. If wheel spins, not the valve. Only one thing left, master cylinder, unless you got ABS brakes, the problem is in the ABS module.


              Noisy Brakes
What kind of noise are you hearing, squealing noise, rattling noise, grinding noise
    

     Let's start with squealing noise


      Some brakes squeal when you push the brakes, some squeal just driving down the road. If it squeals when your just driving and not pushing the brakes, it could be caused by worn down brake pads. There is a warning scrapper on some pads, when the pads get low enough they rub against the rotor and make that squealing noise you hear. If it squeals when your moving and you push the brake pedal, It's probably cause from the pads being glazed. A lot of times this happens when someone changes the brake pads and does not have the rotors replaced or resurfaced. It could also becaused by not putting grease on the surface where the pads ride on the caliper bracket. So to do a complete brake pad replacement job, you should replace or resurface rotors and put grease on the brake pads where they meet the caliper bracket.

        Rattling Noise

    This usually caused by a anti rattling clip missing, or a caliper bushen missing. The caliper bushen is where the caliper bolt goes thru, sometimes it's a spacer where the bolt goes thru the caliper.
    

        Grinding Noise

   This is pretty much a no brainer, you done drove the brake pads clean down to the metal.   





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