Bled my brakes, now brake pedal sinks..
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Bled my brakes, now brake pedal sinks..
Yesterday, I (for the most part) bled my brakes and replaced the brake fluid. However, the rear passenger side drum's bleeder valve snapped and the nut connecting the line to the cylinder was stripping so I skipped that one entirely. So 3 out of 4 brakes were flushed. The reason I bled the brakes in the first place was because after driving for a while, the brake pedal would sink to the floor; I'm assuming it's because whatever water was in the fluid reached boiling point and made air in the system.
Now, the brake pedal is less stiff than it was before and sinks (not all the way) half of the time without even getting hot. I done screwed up or what?
Now, the brake pedal is less stiff than it was before and sinks (not all the way) half of the time without even getting hot. I done screwed up or what?
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Re: Bled my brakes, now brake pedal sinks..
is it possible to loosen the bolt that connects the green line to the wheel cylinder? (mine is starting to strip.) Also what about bad brake fluid? I bought a bottle of prestone dot 3 and the wrapper was peeling off (so were the others that were on the shelf)
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Re: Bled my brakes, now brake pedal sinks..
I took the car for a drive today and realized that the pedal sinks to the floor whenever I'm at a long stop such as a red light. But becomes stiffer when the brake replenishes itself and remains stiff until I hit another long stop. I'm thinking about re-bleeding the brakes again but I need to know how to bleed the rear passenger side drum with the broken valve. Do you have to take out the bolt that connects the green line to the wheel cylinder? Or is there another way? Thanks
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Re: Bled my brakes, now brake pedal sinks..
Sorry for the bump, but I need some advice...
So the other day, I completely re-bled the brakes (all four using the specific pattern) and changed the pads. Tested it out, and it worked good; nice and stiff even at stoplights (first test drive was at night). But then after a couple of drives, it started acting up again. What's happening now is that the sinking (at long stops) is constant during the day when it's warm outside (like it was before I bled the brakes the first time) and is at random (sinking or stiff) during the night/dusk/dawn when it's cool or when the car isn't warmed up completely.
During stops, the pedal will slowly sink all the way to the floor, then I pump the brakes and replenish its stiffness but then sinks back down. I have to leave room between me and the car in front of me so I can keep replenishing the stiffness and not run into the car. I did the booster test and it seems to be working so I can only think of the master cylinder failing or the rotors are bad.
What do you think? What are the chances that it was the master cylinder the whole time? Thanks
So the other day, I completely re-bled the brakes (all four using the specific pattern) and changed the pads. Tested it out, and it worked good; nice and stiff even at stoplights (first test drive was at night). But then after a couple of drives, it started acting up again. What's happening now is that the sinking (at long stops) is constant during the day when it's warm outside (like it was before I bled the brakes the first time) and is at random (sinking or stiff) during the night/dusk/dawn when it's cool or when the car isn't warmed up completely.
During stops, the pedal will slowly sink all the way to the floor, then I pump the brakes and replenish its stiffness but then sinks back down. I have to leave room between me and the car in front of me so I can keep replenishing the stiffness and not run into the car. I did the booster test and it seems to be working so I can only think of the master cylinder failing or the rotors are bad.
What do you think? What are the chances that it was the master cylinder the whole time? Thanks
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Re: Bled my brakes, now brake pedal sinks..
How much should I spend on a new one? I'm seeing them on ebay ranging from $35 to $100+. I found this one for about $80.
http://www.ebay.com/itm/Brake-Master-Cylinder-23-72009-Honda-Civic-Del-Sol-CRX-w-No-ABS-/300671305958?fits=Make%3AHonda&hash=item46016808e6&vxp=mtr
http://www.ebay.com/itm/Brake-Master-Cylinder-23-72009-Honda-Civic-Del-Sol-CRX-w-No-ABS-/300671305958?fits=Make%3AHonda&hash=item46016808e6&vxp=mtr
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Re: Bled my brakes, now brake pedal sinks..
As much as I would like to get the best for my car, I'm actually on a tight budget (18 and no job). So I've decided to go to napa and get one from there for $50 and life time warranty.
After I install the new one, would I have to bleed all four of my brakes again? They should be all full of new fluid and no air. Unless installing a new M.C. would introduce air into the system.
After I install the new one, would I have to bleed all four of my brakes again? They should be all full of new fluid and no air. Unless installing a new M.C. would introduce air into the system.
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From: Hipstercouver, BC...unfortunately
Re: Bled my brakes, now brake pedal sinks..
Any time you remove a hydraulic component/lines. Bleed. Bleed. Bleeeeed.
Bleed it until the system doesn't even know what a bubble is.
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Re: Bled my brakes, now brake pedal sinks..
Yeah I installed the new M.C. last night and the pedal was really spongy however didn't sink. So today I'm going to bleed the whole system. I'll update later with results.
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Re: Bled my brakes, now brake pedal sinks..
After cold night testing and hot day testing, there has been no sinking whatsoever with the brake pedal. The only thing that I've noticed with the new master cylinder is every so often (like right after I get in and start driving; most frequent in parking lots), the pedal clicks/pops/snaps when I apply almost full pressure, but something I don't think of as worrisome (yet). Anyways, I think it's safe to say that replacing the master cylinder fixed the overall problem and I'm now pleased that I don't have a sinking brake pedal. Thanks everyone who helped.
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Re: Bled my brakes, now brake pedal sinks..
i've also experience this problem but very seldom. say at 10 times i stack on traffic only once or twice. should i replace my brake fluid since i dont know when was the last time it has been replaced on 96 civic? and for a 19 year old car, the MC should be replace to a new one? tnx
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Re: Bled my brakes, now brake pedal sinks..
i've also experience this problem but very seldom. say at 10 times i stack on traffic only once or twice. should i replace my brake fluid since i dont know when was the last time it has been replaced on 96 civic? and for a 19 year old car, the MC should be replace to a new one? tnx
1. Bleed your brakes - $8 (brake fluid) [50% success rate]
2. Replace your MC and bleed brakes - $50+ (MC and fluid) [90% success rate]
But I've only been driving/fixing cars for 6 months so I don't know for sure.
Steve at Heart
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Re: Bled my brakes, now brake pedal sinks..
A way to bleed the master cylinder while on the car.
https://honda-tech.com/suspension-br.../#post47188062
https://honda-tech.com/suspension-br.../#post47188062
...................
First, ensure that all of the old fluid is out of the system by bleeding it, or if the car was recently bled, you can do this. It can be done with old fluid, but I don't reccomend it, I'll tell why at the end.
Go buy 12 feet of brake bleeder hose, yes 12 feet. Starting with the right rear brake, connect the bleeder hose to the brake, but instead of using the jug or waste container, run the hose to the master cylinder and stick it in the master cylinder resovoir. Use towels, use duct tape, use whatever you want so it doesn't fall out, because remember: Brake fluid is a mild paint thinner! If you get it on your paint, wash it off right away. Its best not to let brake fluid touch your car's paint at all, finger prints and smears suck.
Now open the bleeder and pump the pedal. Again watch to make sure the fluid level stays above the bottom, keep it at the top. With the bleeder like this, it goes in an endless loop. So any air bubbles at all are now going out the brake hose, into the master cylinder resovoir where they will go to the top and exit, once again, thanks gravity. So with the hose set like this you can go ahead and pump the pedal a hundred times if you'd like. Then of course, close the bleeder, careful with the fluid dripping, and repeat this in the same sequence. Now you don't need to use a shop's vaccum system to remove air with the system. I admit this will be time intensive the first time, but it'll save you money and brake fluid, and helps if you can't get to a shop, or are a track racer who has to bleed his brakes every day opposed to every year.
The reason you don't re-bleed with old dirty fluid is that brake fluid is hygroscopic. It absorbs moisture readily. Thats why you have it capped. Over time, it will absorb moisture because that cap on your master cylinder isn't totally airtight, and as the pads wear, the fluid level goes down. It pulls air in while it goes down. So cycling in old fluid over and over is only going to add more moisture to the system, lowering the boiling point even more. In a full race application, if you cycled fluid through the system, you'd want to go and bleed each brake through with new fluid again.
First, ensure that all of the old fluid is out of the system by bleeding it, or if the car was recently bled, you can do this. It can be done with old fluid, but I don't reccomend it, I'll tell why at the end.
Go buy 12 feet of brake bleeder hose, yes 12 feet. Starting with the right rear brake, connect the bleeder hose to the brake, but instead of using the jug or waste container, run the hose to the master cylinder and stick it in the master cylinder resovoir. Use towels, use duct tape, use whatever you want so it doesn't fall out, because remember: Brake fluid is a mild paint thinner! If you get it on your paint, wash it off right away. Its best not to let brake fluid touch your car's paint at all, finger prints and smears suck.
Now open the bleeder and pump the pedal. Again watch to make sure the fluid level stays above the bottom, keep it at the top. With the bleeder like this, it goes in an endless loop. So any air bubbles at all are now going out the brake hose, into the master cylinder resovoir where they will go to the top and exit, once again, thanks gravity. So with the hose set like this you can go ahead and pump the pedal a hundred times if you'd like. Then of course, close the bleeder, careful with the fluid dripping, and repeat this in the same sequence. Now you don't need to use a shop's vaccum system to remove air with the system. I admit this will be time intensive the first time, but it'll save you money and brake fluid, and helps if you can't get to a shop, or are a track racer who has to bleed his brakes every day opposed to every year.
The reason you don't re-bleed with old dirty fluid is that brake fluid is hygroscopic. It absorbs moisture readily. Thats why you have it capped. Over time, it will absorb moisture because that cap on your master cylinder isn't totally airtight, and as the pads wear, the fluid level goes down. It pulls air in while it goes down. So cycling in old fluid over and over is only going to add more moisture to the system, lowering the boiling point even more. In a full race application, if you cycled fluid through the system, you'd want to go and bleed each brake through with new fluid again.
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