I was backing out of my drive way and pressed my breaks and nothing happened. I kept going! I pumped by breaks hard and now they are working again. Happens every morning!
2007-10-04 05:27:09 · 9 answers · asked by JAZZ M 1 in Cars & Transportation ➔ Maintenance & Repairs
Typically when you have to "pump" the brakes to build up pressure it is because there is a leak in the system, and most commonly this leak is either in the master cylinder or one of the four wheel cylinders (the latter of which are incorporated into the calipers on disk brakes.
The system is basically a foot operated hydraulic pump. You press down on the pedal and it pushes a large piston inside your master cylinder that pushes brake fluid through the brake lines to smaller cylinders at each wheel. When the pistons in those small cylinders are pressed forward they push the brake pads (on disk brakes) or brake shoes (on drum brakes) up against the rotor (on disk brakes) or drum (on drum brakes) thereby creating friction that stops the wheels from turning. When you take your foot off the pedal, the pistons retreat and the brake pads or shoes retreat away from the braking surface on the disks or drums.
Now what any hydaulic pump requires is a liquid medium that cannot be compressed, in this case, brake fluid. That way, when you press the pedal the fluid does not compress under pressure, but instead pushes the pistons in the wheel cylinders to engage the brakes.
When there is air in the system, from a leak, the problem arises that air does compress, and so you have to 'pump" the brakes until you have compressed the air. Typically that leak appears in either a wheel cylinder or caliper or in the master cylinder itself.
2007-10-04 06:31:56 · answer #1 · answered by anonymourati 5 · 0⤊ 0⤋
Sounds like your brakes need priming, so there may be a blockage in the brake fluid like that is causing pressure loss between brake use if you have to pump it to get the pressure. Otherwise it may be a kink in the line or even a leak, though you say that the fluid is to the max then the leak is less likely. Pumping the brake before it works full doesn't indicate the calipers because they would move the same distance regardless of how many times you pump it, only how far/hard into the pedal you push.... Which once again sounds like pressure problems if one side is pressing more than the other.
2016-04-07 03:46:09 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Its sounds like you have air in your brake lines. You need to have your brakes bled. If you turn your wheels all the way to one side you will be able to see a little bleeder screw that looks like a metal nipple. Loosen that slightly and connect a piece of tubing roughly a foot long and put on end on the nipple and the other in a soda bottle. Have someone sit in the vehicle and pump the brakes and hold, while their holding tighten the screw. Do that to every wheel starting with the one furthest away from the master cylinder (right rear passenger) and ending with one that is closest. Afterward fill fluid resevoir to line and that should take care of your problem. Good luck.
2007-10-04 05:34:29 · answer #3 · answered by Spoons 2 · 2⤊ 0⤋
Air in the brake lines. You will want to check your master cylinder which is under the hood normally on the driver's side ofthe engine. If the fluid isnt low you will want to bleed the brakes. If you dont know how to bleed brakes it's harder to do with only one person so you may want to get a friend who knows how to help you.
2007-10-04 06:29:04 · answer #4 · answered by rambo1214 3 · 0⤊ 0⤋
Check the fluid in your master cyl. if it is ok replace your master cyl. If the master is low, refill it and bleed the brakes and do a visual inspection of front and rear hoses and wheel cyl if you have them, ckeck all of youe calipers looking for leaks and ckeck that your friction material dosn't need to be replaced. I wouldn't drive it unless the brakes worked all the time
2007-10-04 05:38:33 · answer #5 · answered by stevet 4 · 0⤊ 0⤋
Rear wheel cylinders are leaking.
You have air in the lines.
Your brake shoes are worn out (rear)
You're low on brake fluid because of the leak.
Don't just add brake fluid.
Have your brakes replaced.
2007-10-04 06:29:32 · answer #6 · answered by Mr. KnowItAll 7 · 0⤊ 0⤋
You probably have air pockets in the line and need to purge them. It isn't difficult but without the proper tools can be messy.
2007-10-04 08:56:29 · answer #7 · answered by german g 1 · 0⤊ 0⤋
Also check the master cycinder checked it could be the seals going.
2007-10-04 05:34:51 · answer #8 · answered by Anonymous · 0⤊ 0⤋
you ether have air in the lines or low on fluid
2007-10-04 05:33:29 · answer #9 · answered by coach 4 · 0⤊ 0⤋