6mmbr

hi
My story:
I replaced all 4 caliper brakes in my '06 with powder coated rebuilt ones. I have done multiple bleeds of all four brakes and no air returns in any lines. I have gone through almost 2 bottles of honda DOT3 doing the bleeds. The brakes work and will stop the car fast enough it makes me a little dizzy (50 year old inner ears!) although I have not had the opportunity to test the ABS. My concern is that the brake pedal does not seems to be as "high and tight" as I think it used to be. 1st pedal press seems a little mushy. Subsequent presses (rapid pumping) it gets more firm. I made sure the slots in the rear piston matched the tab on the pad. I might have let the fluid get too low in the master cylinder during the replacement since I was initially planning to switch to DOT4, but changed my mind and used the OEM honda DOT3. The service manual implies after changing pads that a few braking episodes will restore the pedal to normal "tension", but this has not been the case in my opinion. Before going to the dealer (admission of defeat), I thought I would tap the collective intelligence here. Thank you for your help.

jeff

CKit

Did you change the pads and rotors? Or just the calipers? 2-person bleed or gravity bleed? Is it really spongy and then distinctly firms with pumping or just sort of spongy with sort of improvement? Are you sure that all slides are working and your pads have snugged up to your rotors?

iam7head

1) what consist of the rebuilt of the caliper? did you bake those before you rebuilt them?

2) did you bleed the brake right? running low on fluid during bleeding = time for redo

3) it's a common thing for bubble to be trap after a full flush, most people drive it for a week before rebleeding them again, if you found big amount of air during that time then you have a leak somewhere.

check for leaks in the MC too

CKit

Because a little bit of mushiness is normal if you have worn rotors and pads. The service manual likely refers to full thickness parts which will be firmer.

Maybe the cheapest thing to do is buy a single "solo-bleed" or "speed-bleeder" and pump the crap out of the brake lines to clear a master cylinder bubble. Single, slow pumps might not get it out if you really did suck in a bubble.

Or just go to your dealer and get the brake fluid flushed.

6mmbr

thank you for the responses:

Rebuild consisted of: complete disassembly, steel shot blast metal, professional powder coating, rebuild with original parts using Honda rebuild ket (gaskets, seals, grease, etc). Pistons moved without binding. Used same rotors & pads (16000 mi and well within spec). Calipers moved by hand after initial placement (no fluid in them), now are firm up against rotors and no motion.

1 person gravity bleed with about a 1/2 dixie cup removed from each. I have done this at the initial change and now twice after driving about 5 miles each time.

no leaks seen anywhere.

1st press spongy, and improves "distinctly" after that. When I read in the service manual of testing the vacuum booster; pedal improves with each press" I remember thinking "mine does that, it must be ok". (at work right now can't go give it another subjective test).

Thank you.
jeff

6mmbr

Thank you.
I think I will see if the dealer can flush.
Will they do a "power flush" i.e. push it out from above?

CKit

For less than $10, you can order a couple Earl's solo-bleeds and put one on the valve nearest the master cylinder. It's a one-way ball valve that lets you pump the pedal repeatedly without having to do the two person open-close song and dance. That might very well give you enough flow to push out that air bubble.

I think I bought mne from Summit Racing.

irv_usc

i'm new to the S, but some other cars have a bleeder valve in the master cylinder.

i use a power bleeder and do it myself.

SpitfireS

Its the rear calipers.
The e-brake system is hard (close to impossible in the mounted position) to bleed.
Bleed it while its off the car with the rear of the caliper where the e-brake system is up high.

Gravity bleed works well.

6mmbr

hi
you mean dismount the caliper, hang it so that the e-brake pin bearing is at the lowest position (allowing trapped air bubble to rise) and gravity bleed it at that time? hmmm... rotating it back and forth a few times then might get the bubble out of the piston closer to the reservoir where the bleed screw is (I have a vision of a lava lamp).

I have an appt for a Honda svc flush in the am. If that is not successful I will try this.

thank you

I will report results of the flush tomorrow.