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first time doing my brakes.. need help

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Old 08-25-2007, 11:13 AM
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Default first time doing my brakes.. need help

hi i am putting new rotors, pads and calipers on my 95 se and this is my first brake job... i think i pretty much can do it but i need to no how do i BLEED THE BRAKES and when......

i dont want to mess anything up....
Old 08-25-2007, 12:19 PM
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Well, first of all, good luck...it'* a pretty easy job once you get the hang of it. Basically what you want to do is after you get all of the new parts back in place, you need to find a friend to help you.

Leaving the cap off the master cylinder resevoir, making sure the fluid is full, your friend needs to pump the brake pedal until it becomes somewhat firm. When this happens, open one of the bleeder valves (be sure to have a pan to catch any fluid that may escape the valve) until his foot and the pedal reach the floor. Tighten the valve, and tell him to go again. Don't let him take his foot off the pedal until that valve is tight or you'll release more air into the lines.

Repeat, repeat, repeat, until there'* no more air bubbles coming from the valves when you open them. Your friend will eventually come to the point where the pedal won't reach the floor anymore. This is when you know you're close. Be sure you keep that brake fluid topped off while doing this, or you'll just start a vicious cycle that will never end!

Once that'* all done, put your wheels back on, and take the jacks out. Make sure you're on level ground, and "pump", or apply and release the pedal several times until the pedal returns to normal. Please, PLEASE...when you're driving it for the first time after this, start slow, use caution, and stay in your driveway if you can.

Also:

-Don't lose the rubber cap from the bleeder valve.
-It'* suggested you work from the wheel furthest from the driver first
-Don't over-torque the valve when tightening
-Keep brake fluid off the ground, off your paint, and any rubber/plastic surfaces.
-If you don't feel comfortable with the brake change process, there'* numerous helpful websites that explain everything you need to know, or a Chilton'* manual will help as well.

Hope this helps! Anyone else that cares to chime in with their $.02 feel free!
Old 08-25-2007, 12:53 PM
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If you've never bled brakes before, get a helper who has.

If you're doing this, you should have a service manual of some type.

If you don't have a friend who knows what to do, or a service manual, take it to a competent mechanic.
Old 08-25-2007, 04:14 PM
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Originally Posted by someone who has done this before
OK, The idea is to remove any air bubbles in the brake lines from the master cylinder to each wheel cylinder (rear wheels) or caliper (front wheels).

These directions presume you have a good master cylinder or a new one that has been bench-bled.

You will probably need to remove the rear wheels to gain access to the wheel cylinder bleeders. You may be able to get at the front bleeders on the calipers by turning the wheels all the way left or right. I find bleeding is a lot easier with all the road wheels removed and the car up on stands. Never get under a car supported only by a jack!

Start by filling the master cylinder reservoir and replacing the cap. Don't let brake fluid be exposed to the air - it will absorb moisture from the atmosphere which can cause troubles in the brake lines. What you want is to have a helper pump the pedal a couple of times (press down - release; press down - release) then press down and hold. While he is maintaining pressure on the pedal, you open the bleeder valve on the wheel cylinder or caliper and relieve the pressure by releasing fluid from the bleeder valve. The brake pedal will suddenly go down, at first nearly all the way to the floor. The helper must not allow the pedal to come up while the bleeder valve is open or air will be sucked in through the bleeder valve. At the wheel, when the fluid flow stops, close the bleeder screw and instruct your helper to release the pedal, then "pump and hold" again. After a few times, depending on how much air is in the lines and where the air is located, you will notice as you open the bleeder valve, that the fluid flow is interrupted by escaping air. It kind of makes a "spitting" sound. That is good - that'* the air you are trying to remove. Keep repeating the procedure until the stream of fluid is solid - no air - and clean in appearance.

While you are bleeding each wheel, after about five or six squirts, check the level of fluid in the master cylinder reservoir. If you let the reservoir go empty, you will introduce air into the lines and you will have to bleed the master cylinder and all the brakes again.

I like to place a box wrench on the bleeder screw nut in a position that allows me to both open and close the valve (hopefully) without repositioning the wrench. I then attach a length of flexible vinyl tubing (maybe 3/16" inside diameter) that fits tightly over the end of the nipple on the end of the bleeder. I run the hose into a plastic pan to catch the fluid that comes out. Be careful, brake fluid removes paint. Also, don't use more than a couple of foot-pounds of torque to close these little bleeder screws - they are not solid and they can break off very easily.

There are a couple of inexpensive one-man methods. You can use a vacuum pump to suck out the air from each line, but the problem with that is that you have to open the bleeder screw to open the line and when you do, you usually end up sucking some air through the threads on the bleeder screw making it difficult to know when you have all the air out. An older method is to take the hose described above and put it into a (clean and dry) coke bottle with the end of the hose submerged under a couple of inches of brake fluid. This is not a bad idea, even with a helper, cause if your helper screws up and releases the pedal when the valve is still open, it will suck mostly fluid in from the bottle instead of air. The problem with this method is the same as with the vacuum pump. That is, on the release stroke, if the valve is open, air can be sucked into the system through the threads on the bleeder screw.

Be careful if your bleeder screws are corroded. They will break off in the cylinder or the caliper with surprisingly little force applied, and then you have a real piece of work on your hands. A good plan is to squirt around the bleeder screw (not into it) with a good penetrating oil like power blaster, kroil, or sea foam deep creep (WD-40 is not very good for this). Remove the cap from the screw and give it a couple of taps square on the end of the screw with a small ball-pein hammer, and squirt again to encourage the oil to penetrate the threads. Best if you can let it sit overnight, but give the oil at least 30 minutes to work before you try to open the bleeders.

If your bleeders don't have the little rubber caps on them, make sure the passage is clear to let the fluid out. Sometimes you have to clean them out with a small drill bit.

The traditional method is to start at the wheel farthest from the master cylinder, usually the right rear, and work to the shortest run, i.e., the left front. As you work your way around, the pedal should become firmer and progressively higher from the floor. When you are done, if you have removed all the air, the pedal should be firm, there should be no "sponginess," or softness when depressed.

Good luck!
As stated above, check to make sure the brakes work properly before moving the car anywhere or at any speed at which you might cause damage or injury.


Oh, also, when you are pushing the caliper pistons back into the bore, open the caliper bleeder screw so that the dirty fluid and any accumulated water is not forced back into the master cylinder. Close the bleeder before removing pressure on the piston to prevent sucking in air.
Old 08-25-2007, 09:07 PM
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ok everybody i want to say a big thanks to those that helped as it was a smooth success that only took 45 minutes.. and i had a friend help me bleed the brakes... he is a honda mechanic but bleeding brakes i ssimple... it went alot smoother then i thought it would..

i replaced the pads , calipers and rotors,, now there is no more jerking when i apply the brakes due to worped rotors....
Old 08-25-2007, 09:09 PM
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forgot to mention......

my brake fluid that came out when i took off the calipers was black.? what could this be from.. any ideas? the brakes stop on a dime now and seem 110%
Old 08-25-2007, 09:51 PM
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thats just old brake fluid. thats what happens.
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