brakes spongy after brake pad replacement (didn't open bleeders though)?

Discussion in 'SN95 V6 Mustang Tech' started by jmanng, Aug 23, 2005.

  1. I'm fairly new to mustangs and I had to do my first front pad replacement on my 2000 v6 yesterday night.. and now the brakes feel a bit spongy. It feels like air had gotten into the system but I did not open up the bleeder screws - I just used a C clamp to slowly push the pistons back into their bores. I've done this for eons with other vehicles and never run into this issue. I've searched other posts and I see others are using the same method and didn't find anyone running into the similar problems (on pad replacement without opening the bleeders). Has anyone else experienced this closed system syndrome???

    I'm wondering if I've damaged the MC pushing the pistons back in, although it doesn't seem to drop the pedal (it feels more like air). I guess I'll start with front bleeding to see if it resolves the problem, and then have to look at the MC.

    Any insight would be appreciated.

    2000 v6
  2. Not MC, pedal doesn't drop if it's held steady. I'll start by bleeding the system and changing the brake fluid. Just doesn't add up.
  3. I changed my pads and rotors all around and didn't have the same problem. You did right but just c-clamping the pistons back in.....however I think either the front or rears (don't remember which) need a special tool to twist while pressing in.

    hopefully you didn't damage the cylinder
  4. you have to bleed the MC too if it's ABS
  5. I bleed all the calipers on the weekend starting from the farthest from the MC (but not the MC itself). Well the fluid was pretty dirty and seemed to have a few minute bubbles... so a fluid change was a good thing but the brakes are still spongy for my liking. I'm fairly convinced now that the pedal has always been this way since I got the car at the beginning of the year, but it wasn't until I did the pad replacement and testing the system out that I looked at it with a critical eye (the PO had a certified mechanic doing all of his maintenance)

    The other good thing from looking at the entire system this weekend, was that one of the rear caliper's parking brake mechanism was seized, so I was able to work that free with some penetrating oil (and yep, it's the rear calipers pistons that need to be turned to get them to sink back into their bores).

    I'm going to rebleed the system again starting with the MC (I should have included it to begin with, so now I get to do it over again...). Tom, per your note, yes the car has ABS. From your comment, are you saying that on ABS equipped car, it's standard procedure to bleed MC and all calipers on pad replacement... why is this (understandably if the reservoir went low)??

    Thanks for yor replies,
  6. Every mustang brake job I've done on non-abs never needed to a MC bleed, I'd just leave the cap off and take care the lines. Whenever I did it on my cobra (abs) I wouldn't be able to get all the air out until I did the mc.
  7. That seems to fit this case as well.

  8. How To Bleed Your Brakes in Three Easy Steps

    1.Add brake fluid to the Motive Power Brake Bleeder tank.

    2. Firmly connect the supplied adapter to brake master cylinder and pump the Motive Power Brake Bleeder to pressurize.

    3. Starting with the furthest away brake bleeder valve (typically on the rear of the vehicle), open brake bleeder valve and purge the air and old brake fluid from your brake system.

    For more info visit: Motive Products - Power Bleeder DIY Brake Bleeder
  9. Suggestion. Don't force old brake fluid BACKWARDS through a system with ABS brakes. Open the wheel bleeder screw when compressing the wheel cylinders to let the fluid out the bleeder screw.

    Bleed and flush the system until the fluid is clear and bubble free.