Big Problems!!!Brakes won't Bleed!!! Help
12-15-2005, 09:07 PM
#1
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Big Problems!!!Brakes won't Bleed!!! Help
I installed my LGT brake upgrade (front and rear) yesterday. Install went pretty smooth. Then is came time to bleed. Unfortunately I couldn't recruit my wife to pump the pedal, so I used a mighty vac to such fluid across. I thought this worked pretty well. I buttoned everything up and went for a drive. SPONGY AS HELL!!! This morning I did the tried and true method. Wife was pumping I was bleeding. Again I though everything was good; started it up went down the road, same as before. Chitty mang. Tonight, Jeremy and I broke out the pressure bleeder and forced 32oz of fluid through the system. No bubbles everything is good right? Wrong again, still wicked spongy. What to do? HELP!!!
Jeff
Jeff
12-16-2005, 12:09 AM
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Mine were like that the first few hours of driving after I bleed them, and I thought I did something wrong. After about a hundred miles of driving, they got better and finally had good feel.
Maybe you should try driving your car for a like a hundred miles, do some hard braking sequence and see if things get better?
Maybe you should try driving your car for a like a hundred miles, do some hard braking sequence and see if things get better?
12-16-2005, 11:43 AM
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Jeff, I'm going to ask my friend David for the right order. I know we had to bleed the other David's brakes twice, since the first time we went in the wrong order. I'll give you an update as the day goes on.
12-16-2005, 12:59 PM
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Jeff, here's what I heard from David, this is what we did when we did the Red Subaru 4 Pots & Rear LGT's on the other David's car.
The order is: passenger front, driver rear, passenger rear, driver front.
Notice that you went: pass front, drive rear, drive front, pass rear. It should be the way I posted. Try it again in that fashion, this is out of a text book by the way. Sorry you are having so much trouble with your brakes. After we bled the brakes in the right order (which is the second time we did it) they were rock solid.
The order is: passenger front, driver rear, passenger rear, driver front.
Notice that you went: pass front, drive rear, drive front, pass rear. It should be the way I posted. Try it again in that fashion, this is out of a text book by the way. Sorry you are having so much trouble with your brakes. After we bled the brakes in the right order (which is the second time we did it) they were rock solid.
12-16-2005, 01:08 PM
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That's exactly how I did it.
Good news!!! Car is back from Midas. They had the same problem. They had to bleed it with the engine running. The brakes feel great!!! Just got done done bedding the pads. There is a little rattle I have to find. All in all I pretty happy. I need to get it into the mountains for some fade testing. Thanks or the replies.
Good news!!! Car is back from Midas. They had the same problem. They had to bleed it with the engine running. The brakes feel great!!! Just got done done bedding the pads. There is a little rattle I have to find. All in all I pretty happy. I need to get it into the mountains for some fade testing. Thanks or the replies.
12-16-2005, 01:57 PM
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Originally Posted by Onizuka
Hrm... I thought you would have known to bleed the brakes with the car on? Hehe, oh well, glad it's working man!
actually that is not always necessary, I have never bled my brakes (on any car) with the engine running......but depending on the calipers design, and where the air bubbles are hiding, it may be necessary to have the engine running so you get the power assist for the brakes to help pump fluid through the lines, and get those pesky bubbles out of there that can get stuck. In anycase, I'm glad to hear you got it all worked out Jeff! Good news.
-Ted
12-16-2005, 02:00 PM
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Originally Posted by GotBoost?
actually that is not always necessary, I have never bled my brakes (on any car) with the engine running......but depending on the calipers design, and where the air bubbles are hiding, it may be necessary to have the engine running so you get the power assist for the brakes to help pump fluid through the lines, and get those pesky bubbles out of there that can get stuck. In anycase, I'm glad to hear you got it all worked out Jeff! Good news.
-Ted
-Ted
I would have thought the car needed to be on while it's done. Doesn't the brake vaccuum at a certain point if you pump it too much while the car is off? That's the thing that would lead me to believe you'd have to have the car on, hehe.
Well, that is certainly new info for me
12-16-2005, 02:16 PM
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the brakes dont create a vacuum.....if anything, you would suck air into the line from the master cylinder while bleeding, but that would only happen if you let the level in the reservior to drop too low. Brake systems dont operate on Vacuum.....they operate by the compression of the brake fluid.....but since liquids dont compress, when you step on the pedal the extra pressure applied forces more fluid (from the reservior) into the lines, while (at the other end) the fluid is forced into the calipers, thus making the pistons apply a clamping force onto the rotors via brakepads. Since we have power brakes, if the engine is running, the power assist module for the brakes will also "Pump" the fluid through the lines at a higher pressure than just stepping on the pedal alone would do....but with more pressure......if there is a stubborn air bubble in there somewhere, the extra pressure from the power brake system, will help dislodge the bubble. Plus, as Jeff mentioned.....warped rotors can exacerbate the problem.
-Ted
-Ted