soft pedal after q45 brake upgrade?

[One_love_silvia]

so i just did my 5lug swap, and q45 front brake swap.
heres the just of it:

used q45 calipers
new brake pads for front and rear
new brake rotors for front and rear

we very thoroughly bled the system. once last night and again today. however im still getting a very soft response from the brake pedal. from what ive read, and just using logic, my brake pedal should be fairly stiff after upgrading to q45 brakes in the front, and have all new rotors and pads all around.

im worried that im going to have to replace the BMC. my brakes were working perfectly fine before we did the swap tho. do i need to replace the BMC? do i need to upgrade the size of my BMC?

my brakes still work, but they work even worse than stock 240 brakes, and i have to push all teh way down for them to work.

help please!!:wtc:

[dleep25]

did you flush the whole system? when i did mine they were a bit then i flushed the system and put new fluid. it helped a bit, but you are still going to have more peddle travel since you are basically filling a larger caliper then before.

[One_love_silvia]

no didnt flush the whole system, but for how much we bled them, it should all be brand new fluid. not to mention the fluid that was in there was only like a month old synthetic fluid.

and even if its more pedal travel, it would still have a point where it gets stiff, no?
its like soft all the way through. trying to prevent the use of the word "spongy"

[wangan_cruiser]

how did you bleed them? bleed sequence? you should bleed them this order


rear passenger, rear driver, passenger front then driver front.


i did mine and they were softer than stock. i think u dont have to change the bmc, you could adjust the pedal by looking underneath and there is an adjustable screw right there.

[One_love_silvia]

how did you bleed them? bleed sequence? you should bleed them this order


rear passenger, rear driver, passenger front then driver front.


i did mine and they were softer than stock. i think u dont have to change the bmc, you could adjust the pedal by looking underneath and there is an adjustable screw right there.

ironically enough, thats the exact order we bled them in. il try seeing if i can tighten the brake pedal, but even then the braking will still be worse than stock will it not? from what ive read, the q45 front brake upgrade is supposed to be a day and night difference, and so far, im not pleased. meaning, its not working properly.

anything else i could do to help my brakes work better? im hoping they might get better over time.

[upsdude]

you're just gonna have to keep bleeding them. there's still air in the system. i had the same problem when i did my z32 brakes...we just had to bleed the hell out of the system. buy a big jug of brake fluid and go through the bleeding process another 2-3 times...and no for q45 brakes you don't have to swap out your bmc.

[street240sx]

q45 can run stock 240sx bmc and did you install them on the correct side? with the bleeders pointing up?

[NMs14.5kouki]

how did you bleed them? bleed sequence? you should bleed them this order


rear passenger, rear driver, passenger front then driver front.


i did mine and they were softer than stock. i think u dont have to change the bmc, you could adjust the pedal by looking underneath and there is an adjustable screw right there.


the bleed sequence is actually rear driver, rear passenger, front passenger, front driver.

[One_love_silvia]

ya theyre on the right sides. i just looked at the caliper, and found brake fluid leaking out of the piston boots... its not pooring out, but its still quite a bit. its splashing all around the inside of my fender well...

also, when i took it off, i pushed the brakes in to get a piston out, and only one came out. i went to push that one back in with my fingers, and the other one comes out as i push that one in. is that how these are supposed to work?