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For some reason my brake pedal feels kinda hard now, not mushy at all. The car is a year old now and has 25,5xx miles on it so far. I know how they're suppose to feel and it doesn't feel right for some reason. It feels somewhat shorter and harder. Does anyone know what's wrong w/ them? :dunno:
 

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Harder, shorter, or "wooden" feel indicates possible water contamination.
As water is not compressable it will make the pedal feel very hard.
The only way to remove it is to bleed the system.

You can do it yourself at home with the help of another person.
You'll need the correct size box wrench that will fit the bleeder valve on the caliper, clear silicon tubing which will attache to the bleeder valve, and an empty clear jar with some brake in it this is where the other end of the tubing will go. Make sure the tubing is secure in the jar and that the open end is submersed in brake fluid to ensure that you will not suck any air into the tube. You will also need compatible brake fluid that is brand new, clean, and unopened. NEVER leave brake fluid exposed to air as brake fluid is prone to absorb moisture.

The process is very easy. As you have your box end wrench attached to the bleeder valve and the tubing is attached to the bleeder valve, and the tubes other end is submersed in some brake fluid in a jar you are ready to begin.
Have your assistant pump the brakes 3-5 times and then hold the brake in and steadily apply pressure and keep holding pressure until you say "pump", which will start the process over. Once the assistant has pumped and is now holding steady pressure on the brake, you will lightly crack the bleeder valve enough so that fluid will come through it an into the clear tubing.
MAKE SURE YOUR ASSISSTANT IS STILL APPLYING PRESSURE DURING THE WHOLE TIME. Also, make sure they DO NOT do any pumping of the pedal while you are cracking the valve open, or you will run the risk of sucking in air which will make the bleeding process even longer.
So, once you've cracked the valve open and the fluid flows into the tube, as soon as the fluid stops moving (it may only move about 1/4" at a time), close the valve and tell your assisstant to "pump" again and hold, crack the valve again, more fluid flows, close the valve, pump the brake and hold, open the valve, more fluid, close the valve, pump and hold, etc...
You will repeat this process until you no longer see any bubbles or water.
If you have water, which it seems you do, you will likely see the water very early in the bleed process as it tends to get pushed to the caliper end during normal brake operation. The water will look "gloppy" as it's trying to mix with the brake fluid. You'll want to get that out of there and you'll want to make sure there are no bubbles (air in lines) coming out. Once that is fine, the bleeding is done. Move to the next caliper.
There is normally a caliper you want to start with first. A repair manual will tell you. Or, call a BMW service center and they can tell you in which order to bleed the calipers in. The caliper farthest from the master cylinder will take the most time as the brake is longer and the caliper nearest the master cylinder will take the shortest time.

If you want to change the brake fluid completely then keep repeating the pumping process until you see the new fluid come into the clear tubing.
Once you see the new fluid you know that you have new fluid in that line.

MAKE SURE you keep checking the brake fluid reservoir as you do this process and make sure to keep adding brake fluid. YOU DO NOT want to let the fluid level in the reservoir get low as you can suck air in through that point and it will make bleeding that much longer as you'll then have to remove that air as well. If you have a 3rd person they can keep an eye on the reservoir and keep filling as needed. You can keep the reservoir cap off during this process but make sure to not let it sit exposed to the air too long.

It's very easy. If you need further clarification, just ask or email me.

TT
 

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hamann330ci said:
I'm gonna check my brake fluid levell but if I have to bleed the brakes is that under warranty?
You would have to show that a BMW problem cause water to get into your brakes...which is not likely. Have you done anything to your brake system?

If you are going to have a shop do it I would recommend and independent shop over the dealer, simply to save some money.

Tim
 

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I'm not sure but the warranty is a FULL warranty that is supposed to cover performance as well.
If you have not done anything to the brake system then water may simply have got in. Braking systems are sealed but they are not perfectly sealed.
Even BMW recommends changing the brake fluid every 2 years? I'm not positive about the 2 year thing but I think so.

When the brake caliper pistons push on the pad to engage the brake, a part of the piston is exposed to the atmosphere. Over time small amounts of condensation can bring moisture into the brake system from that area.
If you have a seal that is compromised more than normal, it could be letting even more moisture in than normal. A bad seal would be a part defect.
If the seal was put in incorrectly, it would be a manufacturing defect or both. So, barring brake system changes where you've opened up the system, it should be covered under warranty.

Call a BMW dealer and ask. It can't hurt. :)

TT
 
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