brake problems

[Chris@FreedomMotorsports]

Try this, first take a siphon pump and pull the old oil out of the master to start with and install some fresh new fluid. Then, get a buddy to help and with the engine off, have that buddy to pump the brake pedal about 15-20 times to build up pressure, etc through the pedal and once he gets to that point have him hold it to the floor as tight as he can, while he is holding it there, open the bleeder on one caliper. You may want to hold an open top drain pan out behind the bleeder at an angle to catch the fluid that shoots out. Do this two or three times per caliper to ensure that you are getting new fluid all the way through to the caliper and once you are satisfied that there is no air coming out of that caliper (IE: you have a good strong stream of fluid out of the bleeder) move on to the next caliper. Do this for all of the calipers to ensure that you have properly bled the entire system. Once you are done with that, you should have plenty of pedal if you haven't blown a seal in the master cylinder. IF after doing the full flush in this manner, you still have a soft pedal, then you are probably due for a new master cylinder.

This process is about the best DIY way of getting it done without a machine and taking the ABS into account as well. Making sure to refill the fluid as needed so that it doesn't run dry. Also, while you are doing this, DO NOT leave the cap off, debris isn't the only issue, brake fluid absorbs moisture from the air very quickly, so you really don't want to leave the cap off of the reservoir at all, you also do not want to save brake fluid that has been opened. Once opened, brake fluid has an extremely short shelf life due to it's absorption of moisture.

 

[joshmtz07]

I appreciate it.. same I trying to figure out what happened call I did was pads and rotor and not open anything then noticed the squishy pedal wen car is on put solid wen car is off.. master has full fluied and dint see any leaks anywhere

Did you ever resolved your issue ?
Same thing it’s happening to my 2011 raptor after new rotors and pads

 

[Chris@FreedomMotorsports]

For those experiencing soft pedal after installing new rotors and pads; it's come up many times now since 2013 when this thread was posted. After having several customers come to us with this issue, we finally figured out that the issue arises in the brake master cylinder after collapsing the brake caliper pistons without breaking the bleeder screw loose. Breaking the bleeder screw loose and allowing fluid to escape there, versus forcing fluid backward through the system is the right way to collapse the caliper pistons. Forcing the fluid backward through the system is ruining master cylinders and causing the soft pedal after installing new pads and rotors.

 

[pat247]

Another reason to crack the bleeder valve, as the brake pads wear the resevoir in the caliper gets larger and this fluid sits in the caliper and cooks until time for new pads. This contaminated fluid will cause all sorts of problems with the ABS module so it is best to remove as the piston gets pushed in. Don't let the brake resi run dry when pumping the pedal.

 

[New recaros]

I have these old spring loaded tent poles from a very old tent I destroyed. I wedge it between the seat and brake peddle after pumping the brakes up. Then I bleed one wheel at a time and repeat a couple times for each wheel.

 

[FordTechOne]

For those experiencing soft pedal after installing new rotors and pads; it's come up many times now since 2013 when this thread was posted. After having several customers come to us with this issue, we finally figured out that the issue arises in the brake master cylinder after collapsing the brake caliper pistons without breaking the bleeder screw loose. Breaking the bleeder screw loose and allowing fluid to escape there, versus forcing fluid backward through the system is the right way to collapse the caliper pistons. Forcing the fluid backward through the system is ruining master cylinders and causing the soft pedal after installing new pads and rotors.

This is good practice on all vehicles, especially older ones that have not had the brake fluid changed at regular intervals.

When the old/dirty fuel gets pushed back into the HCU it can cause the dump valves to hang open, which bleeds off pressure. Can’t say I’ve seen it affect a master cylinder, but I suppose it’s possible if the fluid is dirty enough.

 

[Chris@FreedomMotorsports]

Yeah, the ones we've seen here that ruined the master cylinder, all had pretty much never maintained their brake fluid at all. Some of the worst we've seen in that regard, so my thought was the combination of previous lack of maintenance and then forcing fluid backward through the system just did them in.