As dumb as this may sound....... have you tried to simply gravity bleed the brakes and see what happens?


Find it hard that you are still getting no brake pedal pressure after everything you have done....

 

^
what do you mean by gravity bleed?

Tomorrow when I have time I'll check the calipers to see if its a piston

 

my brake issue is early lockup before reaching the grip limit of the tires. I've replaced everything but hardlines trying to track it down (with no luck). anyways, if you get to the point where you need new calipers, just send me a PM. I'm down in the peninsula but might actually be up at infineon next thursday.

have you found many other cases of people having issues with the piston seals?

 

I rebuilt all my calipers as well when I got them powdered, I was having a similar issue where I was not getting the same bite prior to my powder work.


I bled my brakes till I was blue in the face and I was using AMSOIL fluid as well.


Got to the point where I just got my car up on the rack at work and just broke open the bleeders as I was going to bleed em and just let em sit open so the air pockets or blubbles would just find their own way out.

Pedal has been great ever since. Your problem seems a bit more involved as air is some how making into your system, or you are not ridding the system of the air.


Very dumb question......you do have the calipers positioned so that the bleeder is on top on all sides? Yeah.... I know....its worth a shot though.

 

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intresting, yep I have all my bleeder valves pointing up as they should

Grahamab that's a weird brake issue your having, people have problems with the piston seals all the time..they get fried from the heat at the track..and my car was over due for them anyways.

when i did the rebuild my pistons looked ok but maybe I over looked something.


:-/ I have a track day coming up and very little time to actually work on my car

 

Have you tried pulling back on the dust boots to the calipers to see if fluid is making its way passed the actual seal?


I would imagine if it was making its way passed the seal you would see it on the caliper/wheel.......I give up.


Please keep us posted.

 

That's what I'm going to have to do..today or tomorrow ... it might only be a small amount of fluid leaking?

for not having any time to work on my car

 

Made time tonight to work on my car any other suggestions?

 

Activating ABS did not help.

Pedal goes to the floor....

I didn't have time to pull the calipers and check the pistons...I'll keep you guys updated when I do.

 

Hang in there & keep chipping away at this issue. Obviously something not correct

Looking back at what has been changed (Both front calipers rebuilt, Replaced brake master cylinder & replace 1 SST brake line)

Seems to me, the problem lies with one of those components

 

Guys over @ track HQ think I should bench bleed the Brake Master Cylinder

..after I pull the calipers I think I'll try this...gonna use cheap brake fluid this time till I get my firm pedal back...just not looking forward to the extra work to flush in new fluid if that does fix it

 

So I'm back to my original problems, My calipers are still leaking!

looks like the dust boots were keeping most of the fluid from spilling onto the floor..and the leak is small but this has to be my problem

so I'm out 200 dollars for a rebuild kit on top of being out for buying a brand new master cylinder.

So for sale!
Brake Master cylinder
Evo Front Caliper rebuild kit...installed and removed less then 1 mile of use.

 

Hey bro, if you need a rebuild kit, I have a kit for both fronts, yours for free if you PM me your addy.

When you put the seals and stuff in, clean brake fluid is a most and you must make sure the pistons go in VERY straight or it could pinch/tear the seal.

Or you can send me the calipers and i'll rebuild em for you.


Rebuild kit is yours for free if you need it though.

 

^
thanks but I already have a rebuild kit and I just put on a set of brembo's I bought and I'm still having this issue!

help! any idea's?

So recap

brake system wont hold pressure.

replaced MBC...no effect.
noticed brake calipers were leaking from around pistons
rebuilt calipers...still leaked
replaced calipers...still doesn't hold pressure.

notes:
replaced 1 brake line that was damaged during caliper rebuild
if you pump the pedal I get pressure but loose it again
if feels like boiled fluid on the race track.

 

WOW, I am completely out of ideas. Please keep us posted as I cant imagine what the problem is at this point.


How many calipers did you replace? If only two, did you check the others to make sure they were'nt losing fluid too?


Sorry man.........