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Replaced front pads and rotors, then went for a test drive... Brake pedal went way farther to the floor than before. Had a very soft feel to it. Do I need to bleed the MC? Or is there another problem?
 

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More than likely you have air in the system. If you can not get the air out by simply bleeding the brakes, you will need to bleed the MC. Did you allow the MC to run dry when you were changing the brakes?

Dave
 

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Discussion Starter #3
No, I don't think so...Do you know how air can get in the system from changing the rotors/pads?
I'll bleed the brakes later. Thanks.
 

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Replaced front pads and rotors, then went for a test drive... Brake pedal went way farther to the floor than before. Had a very soft feel to it. Do I need to bleed the MC? Or is there another problem?

When changing the rotors, Pads, it is impossible to enter air in the system.

You did use a C clamp, or other means to push the piston back in the calipers, that is a fact we know.

Anytime this is done, the pedal will travel a considerable distance further down till they "The Pistons" are set.

After a pump or two, all should be well.

Dan @ Chockostang
 

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Discussion Starter #6
Okay, but I drove around the block and it didnt get any better. Is there anything else that could contribute to soft brakes?
 

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I agree, no air could have/should have entered. Thinner pads? Crappier pads? Usually only takes a couple pumps until they are normal again, but I do notice a SMALL difference between different brands. Try 'breaking them in' with hard slowdowns then letting them cool.
 

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well yea when i was working in a shop i used the C clamp to push in the pistons. it is possible that if the bleader valve was just opended slightly that when you do this it would suck air in through that hole have you ever noticed that the calipers were covered with fluid. yea and if the MC runs dry then it would suck air in.
 

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yea possible smaller pads, or they are getting jamed on the slides so they are only going in partially. riped any of the break lines because i believe they are metal in the front from the MC they they turn into rubber tube.
 

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My guess would be that you need to get some of that new pad material transfered to those new rotors by 'bedding them in'. Here is the procedure I send out with our kits:

Bedding in Pads & Rotors
Now that you’ve verified the new system works and there are no leaks, its time to bed in the new pads & rotors.

Street or Track LLC does not endorse speeding on public roads and takes no responsibility for any injuries or tickets you may receive while following this procedure.

From a speed of approximately 60mph, gently apply the brakes a couple of times to bring them up to operating temperature. This prevents you from thermally shocking the rotors and pads in the next steps. Make a series of eight near-stops from 60 to about 10 mph. Do it HARD by pressing on the brakes firmly, just shy of locking the wheels. At the end of each slowdown, immediately accelerate back to 60mph. DO NOT COME TO A COMPLETE STOP! If you stop completely and sit for any length of time with your foot on the brake pedal, you will imprint pad material onto the hot rotors, which can lead to vibration, uneven braking, and could even ruin the rotors. With some less aggressive street pads, you may need fewer than eight near-stops. If your pedal gets soft or you feel the brakes going away, then you've done enough. Proceed to the next step. The brakes may begin to fade slightly after the 7th or 8th near-stop. This fade will stabilize, but not completely go away until the brakes have fully cooled. A strong smell from the brakes, and even smoke, is normal. After the 8th near-stop, accelerate back up to speed and cruise for a while, using the brakes as little as possible. The brakes need 5 to 10 minutes to cool down. Try not to become trapped in traffic or come to a complete stop while the brakes are still hot.


After the break-in cycle, there should be a slight blue tint and a light gray film on the rotor face. The blue tint tells you the rotor has reached break-in temperature and the gray film is pad material starting to transfer onto the rotor face. This is what you are looking for. The best braking occurs when there is an even layer of pad material deposited across the face of the rotors. This minimizes squealing, increases braking torque, and maximizes pad and rotor life.


After the first break in cycle shown above, the brakes may still not be fully broken in. A second bed-in cycle, (AFTER the brakes have cooled down fully from the first cycle) may be necessary before the brakes really start to perform well.
 

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well yea when i was working in a shop i used the C clamp to push in the pistons. it is possible that if the bleader valve was just opended slightly that when you do this it would suck air in through that hole have you ever noticed that the calipers were covered with fluid. yea and if the MC runs dry then it would suck air in.
If you had Fluid on your calipers, that indicates either your loosed the bleeders to push in the piston, or a hose leak. Either is a very good chance air has entered.

Clean the pads throughly, reinstall, then bleed the front brakes, I believe this will help.

Then do as Shaun stated, break in the brakes.

GOOD ADVICE Shaun.

Dan @ Chockostang
 

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I'll bet the rear shoes need adjusting. If too loose it will lead to a low brake pedal. Pull the wheel and rotate the drum by hand. Keep tightening the shoes until you can just barely turn it.
 
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