So I have been gathering all of the necessary parts for my Z32/Cobra BBK swap for about 8 months now and installed them yesterday. My current inventory is as follows:
30mm Z32 TT rebuilt calipers
Ford Motorsport 13" Cobra rotors
Jeff92Se's hubcentric rings & relocation brackets
PDM SS lines
Axis semi metallic pads

It looks phenomenal and install was pretty basic and went smooth until I had to bleed the brakes. I didnt even touch the rears and only bled the fronts using a 1 man bleeding kit with the small bottle and clear tubing. I followed the instructions closely until all the air bubbles were extracted from the front hydraulic system and only clear, clean synthetic fluid ran through the lines. Then I noticed that when I was depressing the brake pedal that the fluid was flowing through the lines without any issues but the caliper pistons weren't moving to squeeze the pads onto the rotor! Before installation I thoroughly inspected the rebuilt calipers to ensure proper function (new seals & rings, pistons were greased, all bolts tight etc...).

Could it be that I didn't bleed the rears first? My other thought is that when I installed the front calipers, the pistons were pushed ALL the way in. Could it be that the brake fluid is bypassing the piston cylinders all together due to no space for the fluid to seep in? Should I slide the pistons out a touch then retry the bleeding system? Any thoughs/help is greatly appreciated because my car isn't driveable as of today.

 

How much brake pedal travel do you have when the car is started? Does it stay up near the top or does it become spongy and sink as you push?

 

re bleed the system again, and do all the brakes..

So all pistons aren't moving at all?

 

Did you install the calipers on the correct sides with the bleeders up?

 

You have to bleed the whole system including the rears to get them to work, i had a similar problem when i bled the brakes following the average bleeding procejure for most cars: pass rear, driver rear, pass front, driver front...

I soon learned that this bleeding process worked, but i noticed a HUGE difference on my friends car with the same setup that we installed, and we followed NISSAN'S way of bleeding the brakes, something wierd like pass front driver rear, pass rear driver front or something check the FSM to make sure....I sood did that same process on my 4th gen and it improved the pedal feel and everything...

when i first installed them I only bled the fronts (same setup as you) and i ran into the same problem, only the pistons went down but did not brake at all...pedal just hit the floor pretty much and the calipers were not squeezing as hard as they should...i didnt check to c if they moved at all...i just noticed my car wasnt stopping ...

Im 99% sure you have to rebleed them following the instructions on the FSM...Let us know how it turns out.

 

Calipers are on the right sides. First thing I checked. I just rebled all 4 in order and I have slight grab now, but not enough to stop the car. Pedal is still mush.

 

You got air in the lines. That the only thing it can be mushy pedal= air in line.


I did the same technique you did. Jar with hose and just pumping brakes and the brakes were real mushy but then I picked up a pressurizer kit from a buddy down at automotive shop and well I hooked that up the next day and it got air out I didnt even think was in there. I was getting no air in the jar doing the old technique but when I hooked up the other thing I got alot of air from the fronts. Also some black fluid came out also that was inside the caliper or the line.

 

Yea. I heard the pump is the best thing to do. I'm probably going to invest in one b/c I just did my front brakes and they are grabbing but not the way I want them to. Also, I don't like to waste brake fluid by continuously adding fluid.