mushy brakes

[quikveedb2]

my brakes are less than confidence inspiring; the pedal feels like crap, kinda woody i guess would be a good way to describe it. it requires a pump or 2 to get it feeling ok, which makes me thing the mc has blow a seal & needs to be replaced, or rebuilt if that's a DIY kinda thing. i understand some of these cars have a brake booster, what is that all about, could it be causing my symptoms, or is the mc being blown a pretty safe bet? are these mc's rebuild-able for a competent DIY-er, or should i just get a new one?

[jlevie]

I can't say, based on the information presented, whether you are seeing a "pad knock back" issue or a problem with the brake hydraulics. "pad knock back" occurs when the rotors aren't running totally true and they force the pistons back further than necessary. This situation can be aggravated by worn caliper guide parts. If the pistons retract more than necessary a pump of the brakes will be desirable to reposition everything.

A hard brake pedal would be a sign of a failing brake booster or a problem with the booster vacuum supply. A soft pedal or one that requires pumping, especially one that sinks when holding constant pressure on the brake pedal, would be a sign of a leak in the lines or calipers or a failing master cylinder. A visual inspection will reveal if there are any leaks. Since a leak in the master cylinder can result in brake fluid going into the booster, and since brake fluid will destroy the diaphragm in the booster, if the master cylinder has leaked into the booster both need to be replaced at the same time.

[quikveedb2]

i don't think it's a leak, i'd have found it by now or at least had to add some fluid after using the car as a dd off and on for the past 2 years or so. the pumping of the pedal seems to build pressure, but it does not bleed down quickly, at least as far as i've noticed (but i'll look into it, it seems likely). i'm leaning towards replacing the mc & booster, thanks for the info.

[///digitalme]

mine felt like that...i was told the master cylinder was bad, i replaced it with a good working one, still made the same thing, and changed the booster and solved my problem :), but now i have a bad caliper i need to rebuild it asap!

[briansjacobs]

pull both front wheels and hand turn the rotors, if all seems normal it may be a good time to do a 7 series master cylinder (think I saw someone selling one on here)

if you are running 15's you can buy my wilwood 4 pots :)

[quikveedb2]

whats the advantage of the 7-series mc?

[Uber E30]

no advantage per say, just a firmer pedal, some people like that more.

[llll1l1ll]

7-series MC gave for a lot firmer pedal feel. It was neat.

It's a "direct fit." Some assembly required.