Help with Brakes
#1
12-01-2005 | 02:54 AM
Thread Starter
Joined: Dec 2005
Posts: 2
Help with Brakes
Please bare with me Nub here
When Im driving along and I hit the brakes to slow down, theres no resistance as I push down. The car does begin to slow but its not slowing down quickly. If I let go of the peddle after pushing it all the way down and touch the break again there is resistance immediately. Anyone know whats going on with my car?
When Im driving along and I hit the brakes to slow down, theres no resistance as I push down. The car does begin to slow but its not slowing down quickly. If I let go of the peddle after pushing it all the way down and touch the break again there is resistance immediately. Anyone know whats going on with my car?
#4
12-01-2005 | 10:56 AM
HCF Member
Joined: Feb 2005
Posts: 7,168
From: Jersey
RE: Help with Brakes
you dont need to do that. The only way u need to bleed the brakes is if you removed one of the lines and allowed air to get into it. Chances are you are low on fluid. Either that or your pads need to be replaced.
#5
12-01-2005 | 04:27 PM
HCF Member
Joined: Oct 2005
Posts: 178
From: Omaha, NE
RE: Help with Brakes
ORIGINAL: pcupo12
you dont need to do that. The only way u need to bleed the brakes is if you removed one of the lines and allowed air to get into it.
you dont need to do that. The only way u need to bleed the brakes is if you removed one of the lines and allowed air to get into it.
Taken from http://www.zeckhausen.com/bleeding_brakes.htm
Why bleed brakes?
Fresh brake fluid has a significantly higher boiling point than old fluid, allowing harder braking without fade. This is because brake fluid is hygroscopic and readily absorbs moisture. The more moisture in the fluid, the lower the boiling point.
That same moisture promotes corrosion. Frequent bleeding with fresh fluid allows brake components to last longer. A well maintained brake system can help you avoid having to replace or rebuild calipers or replace an expensive ABS control unit.
The bleeding process may remove air bubbles from the hydraulic system, resulting in firmer brake pedal feel and more linear, responsive braking performance. Too much air in the system can be dangerous and result in the pedal sinking all the way to the floor. Air is compressible, brake fluid is not.
Fresh brake fluid has a significantly higher boiling point than old fluid, allowing harder braking without fade. This is because brake fluid is hygroscopic and readily absorbs moisture. The more moisture in the fluid, the lower the boiling point.
That same moisture promotes corrosion. Frequent bleeding with fresh fluid allows brake components to last longer. A well maintained brake system can help you avoid having to replace or rebuild calipers or replace an expensive ABS control unit.
The bleeding process may remove air bubbles from the hydraulic system, resulting in firmer brake pedal feel and more linear, responsive braking performance. Too much air in the system can be dangerous and result in the pedal sinking all the way to the floor. Air is compressible, brake fluid is not.
Taken from http://www.stoptech.com/tech_info/wp...edbrakes.shtml
Why Bleed the Brakes?
The term "bleeding the brakes" refers to the process in which a small valve is opened at the caliper (or wheel cylinder) to allow controlled amounts of brake fluid to escape the system. (When you think about it, "bleeding" may appear to be a somewhat graphic term, but it aptly describes the release a vital fluid.)
We bleed the brakes to release air that sometimes becomes trapped within the lines. Technically, "air" only enters the lines if there is a compromise of the system's sealing (as when flex lines are removed or replaced), because when fluid boils, it will instead create "fluid vapor." Vapor in the brake fluid, like air, will create an efficiency loss in the braking system. However, for the sake of simplicity we use the term "air" throughout this article to describe both air and fluid vapor.
When air (or vapor) becomes present within the lines, it creates inefficiencies within the system because, unlike liquid, air can be compressed. So when enough air fills the lines, input at the pedal merely causes the air to compress instead of creating pressure at the brake corners. In other words, when air is present within the system, the efficiency and effectiveness of the braking system is reduced. Usually, a small amount of air within the brake system will contribute to a "mushy" or "soft" pedal (since less energy is required to compress the air than is required to move fluid throughout the brake lines.) If enough air enters the brake system, it can result in complete brake failure.
So how does air enter the lines in the first place? Sometimes, it can be the result of a service procedure or an upgrade – such as replacing the stock flex lines with stainless steel braided lines. But often it is the result of high temperatures that cause brake fluid components to boil, thus releasing gasses from the boiling fluid into the brake hydraulic system.
The term "bleeding the brakes" refers to the process in which a small valve is opened at the caliper (or wheel cylinder) to allow controlled amounts of brake fluid to escape the system. (When you think about it, "bleeding" may appear to be a somewhat graphic term, but it aptly describes the release a vital fluid.)
We bleed the brakes to release air that sometimes becomes trapped within the lines. Technically, "air" only enters the lines if there is a compromise of the system's sealing (as when flex lines are removed or replaced), because when fluid boils, it will instead create "fluid vapor." Vapor in the brake fluid, like air, will create an efficiency loss in the braking system. However, for the sake of simplicity we use the term "air" throughout this article to describe both air and fluid vapor.
When air (or vapor) becomes present within the lines, it creates inefficiencies within the system because, unlike liquid, air can be compressed. So when enough air fills the lines, input at the pedal merely causes the air to compress instead of creating pressure at the brake corners. In other words, when air is present within the system, the efficiency and effectiveness of the braking system is reduced. Usually, a small amount of air within the brake system will contribute to a "mushy" or "soft" pedal (since less energy is required to compress the air than is required to move fluid throughout the brake lines.) If enough air enters the brake system, it can result in complete brake failure.
So how does air enter the lines in the first place? Sometimes, it can be the result of a service procedure or an upgrade – such as replacing the stock flex lines with stainless steel braided lines. But often it is the result of high temperatures that cause brake fluid components to boil, thus releasing gasses from the boiling fluid into the brake hydraulic system.
#6
12-01-2005 | 04:37 PM
HCF Member
Joined: Oct 2005
Posts: 178
From: Omaha, NE
RE: Help with Brakes
ORIGINAL: DavidHLd
How do you bleed your brakes?>
How do you bleed your brakes?>
How-To
So, now that you understand the need behind bleeding your brakes, let us present just one procedure that can be utilized when servicing your own car. Note that unless you are replacing your master cylinder, the procedure is the same whether you have a vehicle equipped with ABS or not…
Supplies Required
You will need the following tools:
· Box-end wrench suitable for your car's bleeder screws. An offset head design usually works best.
· Extra brake fluid (about 1 pint if you are just bleeding, about 3 if you are completely replacing).
· 12-inch long section of clear plastic tubing, ID sized to fit snugly over your car's bleeder screws.
· Disposable bottle for waste fluid.
· One can of brake cleaner.
· One assistant (to pump the brake pedal).
Vehicle Preparation and Support
1. Loosen the lug nuts of the road wheels and place the entire vehicle on jackstands. Be sure that the car is firmly supported before going ANY further with this procedure!
2. Remove all road wheels.
3. Install one lug nut backward at each corner and tighten the nut against the rotor surface. Note that this step is to limit caliper flex that may distort pedal feel.
4. Open the hood and check the level of the brake fluid reservoir. Add fluid as necessary to ensure that the level is at the MAX marking of the reservoir. Do not let the reservoir become empty at any time during the bleeding process!
Bleeding Process
1. Begin at the corner furthest from the driver and proceed in order toward the driver. (Right rear, left rear, right front, left front.) While the actual sequence is not critical to the bleed performance it is easy to remember the sequence as the farthest to the closest. This will also allow the system to be bled in such a way as to minimize the amount of potential cross-contamination between the new and old fluid.
2. Locate the bleeder screw at the rear of the caliper body (or drum brake wheel cylinder.) Remove the rubber cap from the bleeder screw – and don't lose it!
3. Place the box-end wrench over the bleeder screw. An offset wrench works best – since it allows the most room for movement.
4. Place one end of the clear plastic hose over the nipple of the bleeder screw.
5. Place the other end of the hose into the disposable bottle.
6. Place the bottle for waste fluid on top of the caliper body or drum assembly. Hold the bottle with one hand and grasp the wrench with the other hand.
7. Instruct the assistant to "apply." The assistant should pump the brake pedal three times, hold the pedal down firmly, and respond with "applied." Instruct the assistant not to release the brakes until told to do so.
8. Loosen the bleeder screw with a brief ¼ turn to release fluid into the waste line. The screw only needs to be open for one second or less. (The brake pedal will "fall" to the floor as the bleeder screw is opened. Instruct the assistant in advance not to release the brakes until instructed to do so.)
9. Close the bleeder screw by tightening it gently. Note that one does not need to pull on the wrench with ridiculous force. Usually just a quick tug will do.
10. Instruct the assistant to "release" the brakes. Note: do NOT release the brake pedal while the bleeder screw is open, as this will suck air back into the system!
11. The assistant should respond with "released."
12. Inspect the fluid within the waste line for air bubbles.
13. Continue the bleeding process (steps 11 through 16) until air bubbles are no longer present. Be sure to check the brake fluid level in the reservoir after bleeding each wheel! Add fluid as necessary to keep the level at the MAX marking. (Typically, one repeats this process 5-10 times per wheel when doing a ‘standard' bleed.)
14. Move systematically toward the driver – right rear, left rear, right front, left front - repeating the bleeding process at each corner. Be sure to keep a watchful eye on the brake fluid reservior! Keep it full!
15. When all four corners have been bled, spray the bleeder screw (and any other parts that were moistened with spilled or dripped brake fluid) with brake cleaner and wipe dry with a clean rag. (Leaving the area clean and dry will make it easier to spot leaks through visual inspection later!) Try to avoid spraying the brake cleaner DIRECTLY on any parts made of rubber or plastic, as the cleaner can make these parts brittle after repeated exposure.
16. Test the brake pedal for a firm feel. (Bleeding the brakes will not necessarily cure a "soft" or "mushy" pedal – since pad taper and compliance elsewhere within the system can contribute to a soft pedal. But the pedal should not be any worse than it was prior to the bleeding procedure!)
17. Be sure to inspect the bleeder screws and other fittings for signs of leakage. Correct as necessary.
18. Properly dispose of the used waste fluid as you would dispose of used motor oil. Important: used brake fluid should NEVER be poured back into the master cylinder reservoir!
Vehicle Wrap-Up and Road Test
1. Re-install all four road wheels.
2. Raise the entire vehicle and remove jackstands. Torque the lug nuts to the manufacturer's recommended limit. Re-install any hubcaps or wheel covers.
3. With the vehicle on level ground and with the car NOT running, apply and release the brake pedal several times until all clearances are taken up in the system. During this time, the brake pedal feel may improve slightly, but the brake pedal should be at least as firm as it was prior to the bleeding process.
4. Road test the vehicle to confirm proper function of the brakes. USE CAUTION THE FIRST TIME YOU DRIVE YOUR CAR AFTER MODIFICATION TO ENSURE THE PROPER FUNCTION OF ALL VEHICLE SYSTEMS!
So, now that you understand the need behind bleeding your brakes, let us present just one procedure that can be utilized when servicing your own car. Note that unless you are replacing your master cylinder, the procedure is the same whether you have a vehicle equipped with ABS or not…
Supplies Required
You will need the following tools:
· Box-end wrench suitable for your car's bleeder screws. An offset head design usually works best.
· Extra brake fluid (about 1 pint if you are just bleeding, about 3 if you are completely replacing).
· 12-inch long section of clear plastic tubing, ID sized to fit snugly over your car's bleeder screws.
· Disposable bottle for waste fluid.
· One can of brake cleaner.
· One assistant (to pump the brake pedal).
Vehicle Preparation and Support
1. Loosen the lug nuts of the road wheels and place the entire vehicle on jackstands. Be sure that the car is firmly supported before going ANY further with this procedure!
2. Remove all road wheels.
3. Install one lug nut backward at each corner and tighten the nut against the rotor surface. Note that this step is to limit caliper flex that may distort pedal feel.
4. Open the hood and check the level of the brake fluid reservoir. Add fluid as necessary to ensure that the level is at the MAX marking of the reservoir. Do not let the reservoir become empty at any time during the bleeding process!
Bleeding Process
1. Begin at the corner furthest from the driver and proceed in order toward the driver. (Right rear, left rear, right front, left front.) While the actual sequence is not critical to the bleed performance it is easy to remember the sequence as the farthest to the closest. This will also allow the system to be bled in such a way as to minimize the amount of potential cross-contamination between the new and old fluid.
2. Locate the bleeder screw at the rear of the caliper body (or drum brake wheel cylinder.) Remove the rubber cap from the bleeder screw – and don't lose it!
3. Place the box-end wrench over the bleeder screw. An offset wrench works best – since it allows the most room for movement.
4. Place one end of the clear plastic hose over the nipple of the bleeder screw.
5. Place the other end of the hose into the disposable bottle.
6. Place the bottle for waste fluid on top of the caliper body or drum assembly. Hold the bottle with one hand and grasp the wrench with the other hand.
7. Instruct the assistant to "apply." The assistant should pump the brake pedal three times, hold the pedal down firmly, and respond with "applied." Instruct the assistant not to release the brakes until told to do so.
8. Loosen the bleeder screw with a brief ¼ turn to release fluid into the waste line. The screw only needs to be open for one second or less. (The brake pedal will "fall" to the floor as the bleeder screw is opened. Instruct the assistant in advance not to release the brakes until instructed to do so.)
9. Close the bleeder screw by tightening it gently. Note that one does not need to pull on the wrench with ridiculous force. Usually just a quick tug will do.
10. Instruct the assistant to "release" the brakes. Note: do NOT release the brake pedal while the bleeder screw is open, as this will suck air back into the system!
11. The assistant should respond with "released."
12. Inspect the fluid within the waste line for air bubbles.
13. Continue the bleeding process (steps 11 through 16) until air bubbles are no longer present. Be sure to check the brake fluid level in the reservoir after bleeding each wheel! Add fluid as necessary to keep the level at the MAX marking. (Typically, one repeats this process 5-10 times per wheel when doing a ‘standard' bleed.)
14. Move systematically toward the driver – right rear, left rear, right front, left front - repeating the bleeding process at each corner. Be sure to keep a watchful eye on the brake fluid reservior! Keep it full!
15. When all four corners have been bled, spray the bleeder screw (and any other parts that were moistened with spilled or dripped brake fluid) with brake cleaner and wipe dry with a clean rag. (Leaving the area clean and dry will make it easier to spot leaks through visual inspection later!) Try to avoid spraying the brake cleaner DIRECTLY on any parts made of rubber or plastic, as the cleaner can make these parts brittle after repeated exposure.
16. Test the brake pedal for a firm feel. (Bleeding the brakes will not necessarily cure a "soft" or "mushy" pedal – since pad taper and compliance elsewhere within the system can contribute to a soft pedal. But the pedal should not be any worse than it was prior to the bleeding procedure!)
17. Be sure to inspect the bleeder screws and other fittings for signs of leakage. Correct as necessary.
18. Properly dispose of the used waste fluid as you would dispose of used motor oil. Important: used brake fluid should NEVER be poured back into the master cylinder reservoir!
Vehicle Wrap-Up and Road Test
1. Re-install all four road wheels.
2. Raise the entire vehicle and remove jackstands. Torque the lug nuts to the manufacturer's recommended limit. Re-install any hubcaps or wheel covers.
3. With the vehicle on level ground and with the car NOT running, apply and release the brake pedal several times until all clearances are taken up in the system. During this time, the brake pedal feel may improve slightly, but the brake pedal should be at least as firm as it was prior to the bleeding process.
4. Road test the vehicle to confirm proper function of the brakes. USE CAUTION THE FIRST TIME YOU DRIVE YOUR CAR AFTER MODIFICATION TO ENSURE THE PROPER FUNCTION OF ALL VEHICLE SYSTEMS!
#7
12-01-2005 | 10:37 PM
HCF Member
Joined: Jun 2004
Posts: 7,699
RE: Help with Brakes
nice. but you had that info a bit wrong. i think you understand it, but to make it clearer to anyone else, the water that is absorbed into the fluid isnt the problem itself, its the fact that it lowers the boiling point enough to make it easy to boil and introduce the air bubbles into the lines.
#8
12-01-2005 | 10:45 PM
HCF Member
Joined: Oct 2005
Posts: 178
From: Omaha, NE
RE: Help with Brakes
ORIGINAL: sacicons
nice. but you had that info a bit wrong. i think you understand it, but to make it clearer to anyone else, the water that is absorbed into the fluid isnt the problem itself, its the fact that it lowers the boiling point enough to make it easy to boil and introduce the air bubbles into the lines.
nice. but you had that info a bit wrong. i think you understand it, but to make it clearer to anyone else, the water that is absorbed into the fluid isnt the problem itself, its the fact that it lowers the boiling point enough to make it easy to boil and introduce the air bubbles into the lines.
Umm... You didn't say anything different than I did.
One of the reasons I understand brakes so well is because my buddies Todd owns and runs TCE Performance Products in AZ. I'll bug him anytime I've got a question.
#9
12-01-2005 | 11:13 PM
HCF Member
Joined: Jun 2004
Posts: 7,699
RE: Help with Brakes
Once water is absorbed, the hydraulic composition of the fluid has been compromised and will not work as well.
#10
12-01-2005 | 11:16 PM
HCF Member
Joined: Oct 2005
Posts: 178
From: Omaha, NE
RE: Help with Brakes
ORIGINAL: sacicons
thats what i meant, you make it sound like the water actually makes the fluid not work hydraulically as well, but its actually just the boiling point change. if it stayed cool, water "could" work. (not well though, but for many reasons, lubrication and rusting being 2.)
Once water is absorbed, the hydraulic composition of the fluid has been compromised and will not work as well.
Actually, it's slightly both.