HELP! soft brake pedal after brake fluid flush!
#1
HELP! soft brake pedal after brake fluid flush!
so yesterday i painted my drums and calipers, and flushed my brake fluid. i don't believe it has ever been done, and the truck is at 40k miles. here's how i did it;
with the truck off, and starting at the rear passenger tire, i had a friend open the bleeder valve. i would pump the brakes a couple times, fill some new fluid into the reservoir, and repeat the process until new fluid was coming out the line. on my last pump, i'd hold the pedal down while my friend tightened the bleeder valve. i repeated this process with the rear driver tire, then the front passenger tire, and finally the front driver tire.
i drove my truck today and something definitely seems wrong. my brakes still seem to work fine, but the pedal seems softer, and it seems like i have to push down farther/harder to get the truck to slow.
any ideas on resolving this?
with the truck off, and starting at the rear passenger tire, i had a friend open the bleeder valve. i would pump the brakes a couple times, fill some new fluid into the reservoir, and repeat the process until new fluid was coming out the line. on my last pump, i'd hold the pedal down while my friend tightened the bleeder valve. i repeated this process with the rear driver tire, then the front passenger tire, and finally the front driver tire.
i drove my truck today and something definitely seems wrong. my brakes still seem to work fine, but the pedal seems softer, and it seems like i have to push down farther/harder to get the truck to slow.
any ideas on resolving this?
#8
#10
Originally Posted by NicksterSVT
with the bleeder CLOSED, pump the pedal 3 times, on the third time down, hold it. Open the bleeder with the pedal depressed(down) until it goes to the floor. Close the bleeder before releasing the pedal. repeat these steps until you have a full pedal.
Bingo idk what you where doing man you shouldnt do that. every time you get the foot to the floor you close the bleeder. otherwise you just suck air back in. you might have quite a decent amount of air to get out of the system now...
#11
ok here this artical might help you. honistly you dont need to flush your brake fluid unless there is water or the fluid is dirty. after a normal brake job and replaceing the rotors and wheel cyclinder like your susposed to the "bleeding" process should take out enough to "clean" that is unless the fluid got contaminated. now brake fluid can brake down over time but it isnt like a 30000 mile thing.
To do this flush, we open the brake lines located at each wheel and allow the brake fluid from the brake master cylinder to "gravity bleed" as we continue to feed new fluid to the master cylinder until the fluid runs clear at all wheels. By gravity bleed I mean without the assistance of anything other than allowing the fluid to slowly drip from the lines by the natural force of gravity.
You are probably familiar with the term "bleeding the brakes" when talking about a brake job. When the brake lines are opened or any work is performed to the brake system that can allow air to get trapped within the lines, the brakes must be bled of air. In the earlier days, the mechanic would bleed the brakes by having someone pump and hold pressure on the brake pedal as he opened the brake lines located at each wheel. This method of bleeding the brakes is not a recommended procedure for newer brake systems (discussed later).
What is the difference between flushing and bleeding? Flushing is just that, flushing the old dirty fluid out of the system and replacing it with new clean fluid. Bleeding usually consists of removing just enough brake fluid to get out the air pockets that have become trapped in the system, and usually does not focus on the time consuming process of removing the dirt and old fluid from the system.
One side note learned by experience. If you are interested in doing a brake fluid flush on your own vehicle, be warned of the potential dangers. Foremost, follow the brake bleeding procedures outlined in the repair manual you should be using. Stepping on the brake pedal with the brake lines cracked open can cause the dirt and debris to be pushed into the body of the master cylinder, thus causing damage to internal parts and seals of the master cylinder and the anti-lock brake components. Stepping on the brake pedal as someone under the vehicle opens each brake line at the wheel used to be the way you bled brakes, but not anymore.
Gravity bleeding does take a little longer to perform and can require a lot of new brake fluid to push out the old dirty fluid, but the risk of doing internal damage to the anti-lock system is greatly reduced. They also make vacuum assisted brake bleeding and flushing equipment to help speed up the process.
How can you tell if your vehicle is due for a brake fluid flush? They make special test strips which can detect high levels of moisture present in the brake fluid, but I prefer the old fashioned eye ball method personally. Remove the brake master cylinder cap and visually inspect the condition of the fluid. Brake fluid should be clear or a slight yellowish tent, so black or dark colored dirty fluid should be quite obvious even to the untrained eye.
You can get excellent tips like this and advice on how to not get ripped off by your mechanic by buying my ebook "What Your Mechanic Doesn't Want You to Know"
Click Here to learn more.
You are probably familiar with the term "bleeding the brakes" when talking about a brake job. When the brake lines are opened or any work is performed to the brake system that can allow air to get trapped within the lines, the brakes must be bled of air. In the earlier days, the mechanic would bleed the brakes by having someone pump and hold pressure on the brake pedal as he opened the brake lines located at each wheel. This method of bleeding the brakes is not a recommended procedure for newer brake systems (discussed later).
What is the difference between flushing and bleeding? Flushing is just that, flushing the old dirty fluid out of the system and replacing it with new clean fluid. Bleeding usually consists of removing just enough brake fluid to get out the air pockets that have become trapped in the system, and usually does not focus on the time consuming process of removing the dirt and old fluid from the system.
One side note learned by experience. If you are interested in doing a brake fluid flush on your own vehicle, be warned of the potential dangers. Foremost, follow the brake bleeding procedures outlined in the repair manual you should be using. Stepping on the brake pedal with the brake lines cracked open can cause the dirt and debris to be pushed into the body of the master cylinder, thus causing damage to internal parts and seals of the master cylinder and the anti-lock brake components. Stepping on the brake pedal as someone under the vehicle opens each brake line at the wheel used to be the way you bled brakes, but not anymore.
Gravity bleeding does take a little longer to perform and can require a lot of new brake fluid to push out the old dirty fluid, but the risk of doing internal damage to the anti-lock system is greatly reduced. They also make vacuum assisted brake bleeding and flushing equipment to help speed up the process.
How can you tell if your vehicle is due for a brake fluid flush? They make special test strips which can detect high levels of moisture present in the brake fluid, but I prefer the old fashioned eye ball method personally. Remove the brake master cylinder cap and visually inspect the condition of the fluid. Brake fluid should be clear or a slight yellowish tent, so black or dark colored dirty fluid should be quite obvious even to the untrained eye.
You can get excellent tips like this and advice on how to not get ripped off by your mechanic by buying my ebook "What Your Mechanic Doesn't Want You to Know"
Click Here to learn more.
#12
yeah my fluid was ridiculously dark... definitely ready for a flush. i'm going to redo it today, and i was reading the service manual and saw this;
--
CAUTION: Do not allow the brake master cylinder reservoir to run dry during the bleeding operation. Keep the brake master cylinder reservoir filled with the specified brake fluid. Never reuse the brake fluid that has been drained from the hydraulic system.
--
what happens if the master cylinder runs dry?
--
CAUTION: Do not allow the brake master cylinder reservoir to run dry during the bleeding operation. Keep the brake master cylinder reservoir filled with the specified brake fluid. Never reuse the brake fluid that has been drained from the hydraulic system.
--
what happens if the master cylinder runs dry?
#13
umm....master cyl runs dry = start over. You've put air in the system. Air in the system = disaster/not good at all. Hydraulic braking systems use fluid to push the shoes/pistons into the friction surface. air = death to your brakes....they'll still kinda work, but not well at all. Yea...do the rebleed you'll should be fine.
Like what Nick said, but as soon as your foot hits the floor, shut off that screw. It is a two person job to get it all done right, unless you have "speed bleeder screws". I've got those on my chevy and are awesome. 1 person bleeding = awesomeness.
Good luck.
Like what Nick said, but as soon as your foot hits the floor, shut off that screw. It is a two person job to get it all done right, unless you have "speed bleeder screws". I've got those on my chevy and are awesome. 1 person bleeding = awesomeness.
Good luck.
#14
#15
Originally Posted by barrman
yeah my fluid was ridiculously dark... definitely ready for a flush. i'm going to redo it today, and i was reading the service manual and saw this;
--
CAUTION: Do not allow the brake master cylinder reservoir to run dry during the bleeding operation. Keep the brake master cylinder reservoir filled with the specified brake fluid. Never reuse the brake fluid that has been drained from the hydraulic system.
--
what happens if the master cylinder runs dry?
--
CAUTION: Do not allow the brake master cylinder reservoir to run dry during the bleeding operation. Keep the brake master cylinder reservoir filled with the specified brake fluid. Never reuse the brake fluid that has been drained from the hydraulic system.
--
what happens if the master cylinder runs dry?
#16
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