Soft brake pedal culprits?

[DONWATERS]

I would replace the master cylinder, maybe first looking at the brake hoses for bulges while someone holds the pedal down first.

 

[nthach]

Originally Posted by HangFire
Originally Posted by nthach
That's what I'm going to grab this weekend - https://www.harborfreight.com/4-piece-fluid-line-clamp-set-65116.html

Maybe it's just me... but I wouldn't use fluid clamps on original 2001 hoses. Really I wouldn't use them on brake hoses at all, but really not on 17 year old hoses. Maybe I'm just being superstitious... but if I were in there doing brake work, I would just replace the hoses, and the rear brake cylinders too.

And brake hoses are cheap for these things at Rock and Amazon too.

I've ordered a new aftermarket MC and hoses off Rock. We'll see what happens next.

 

[08z06]

Originally Posted by 14Accent
If it's still soft after you bleed, there may not be a leak OR air in the system. Seized from caliper pins will give you a low, mushy pedal, as will mis-adjusted rear drums (if I remember right, base Eclipse's had rear drums). If you have those plastic hose-clamp pliers just pinch off all 4 brake hoses (after you bleed) and pump up the pedal gently. If it firms up, you know the issue is post-brake hose. If it DOES fade, you have a failed master (or possibly ABS hydraulic unit, if equipped).

Remove the hose clamps one corner at a time a repeat the test. When your pedal drops again, you've found your culprit. Or, at least where to further your diagnosis.

EXACTLY

 

[HangFire]

Originally Posted by nthach
Originally Posted by HangFire
Originally Posted by nthach
That's what I'm going to grab this weekend - https://www.harborfreight.com/4-piece-fluid-line-clamp-set-65116.html

Maybe it's just me... but I wouldn't use fluid clamps on original 2001 hoses. Really I wouldn't use them on brake hoses at all, but really not on 17 year old hoses. Maybe I'm just being superstitious... but if I were in there doing brake work, I would just replace the hoses, and the rear brake cylinders too.

And brake hoses are cheap for these things at Rock and Amazon too.

I've ordered a new aftermarket MC and hoses off Rock. We'll see what happens next.

Cool, keep us posted. Sometimes it's better just to replace old stuff then figure out what went last (and wonder what goes next).

 

[nthach]

Yesterday, I bled and installed a new Car-Be-Done select MC - it was made in Taiwan. There was some improvement to the pedal - but it was still soft. I wanted to install new pads and rotors anyway so I installed new Centric C-Tek rotors, NOS Raybestos QS brake pads off Rock and Sunsong hoses. When I proceeded to take apart the passenger's side front wheel, the culprit was staring right in front of me - the inboard brake pad was down to the backing plate and shim.

When I tore things down to get even deeper, the piston boot was cut and I was able to remove the piston - surprisingly the piston is in great shape and the bore is in good shape with no rust or corrosion. Since it's still an OEM caliper, I'm gonna throw a seal kit on this. I clamped off the soon to be replaced hose with a pair of vise-grips and the pedal is now firm. Car ain't going anywhere.

The OEM MC is probably still good - but no sense in returning it to Rock now.