Okay, so I have a 91 dx and I just put disc brakes on it, from a crx si
Bought brand new 300 calipers for the rear and new rotors pads all around.

Heres the problem... I can't get the brakes to work correctly

Heres what Im using...
Stock 91 dx MC and booster.
DA 4040 valve
Crx Si discs trailing arms in rear
stock disc setup in the front


Ive done some reading on here, and ive bled them several times pass rear, driver front, driver rear, pass front...
so the pedel is rock hard when OFF and as soon as i start the car they go weak.
when I drive the car I can push it all the way to the floor and it still does not want to stop the car unless i pump them a bunch... 20 to 0 mph verrrry untrusted!! LOL
please help someone everything worked before the swap... and everything is new..
no leaks in the lines..
can't figure it out.
Thanks in advance

 

if you are are having to pump the brakes to get pressure it means there is air in the lines. i'd suggest getting a pneumatic brake bleeding kit that uses air movement to create a vacuum that draws all of the air out. 1 person can do it and it cuts the time to almost nil.

 

Okay im on my way to shucks right now....
Ill try that and be back in a hour or so with a verdict.
Ive never had disc brakes all around so im super stoked to get these working properly... and have room to stop on a dime if needed..
thanks again

 

also, now i personally have not had this problem before, but it is also recommended to bench bleed the master cylinder any time you swap out the proportioning valve, master cylinder, or brakes booster, or any combination of the three. just a possibility. but again like i said, any time i have changed out just the proportioning valve, i have never had a problem without bench bleeding th m/c.

 

here...

 

Thank you both... I will try checking those tommarow Clipsed.
I bled them again today and it got a little better... still having to pump the brakes multiple times to get it to grab barely..
Tommarow is the day, Hopefully after a few more bleeeds and checking those diagrams it will be perfect.

any one else have any input on bench bleeding the MC if I changed the prop valve?
thanks

 

aanother thing... a friend of mine today at work, also plays with hondas :D
he told me to try bleeding them with the car running :/ says hes had to do it before...
will this hurt anything or safe or just a no go ? haha
ready to fix this :D

 

Id go with ef's advice, and then if you still have problems, then id replace the booster/cylinder. And when you do that you have life time warranty, which means if people need those parts, you can sell your warranty to them! Lol

 

haha thats good thinkin... just take their broken one in?

and must have been massive air in the lines from dripping all day ad then hooking everything up.. cause went out this morning bled them once and it works semi good.... enough i can drive around on and bleed them in about a week or so and hopefully be back in full swing...
was kinda happy when i put my foot to the floor and all 4 locked up ;/
hahah
i SHOUULD have taken pics and wrote a great write up because as far as ive read all these dx drums to si disc write ups... suck
thanks again for everyones help

 

since i don't have a machine to help me, i always bleed my brakes with the vehicle on and running so i get a real time feel. plus i've always thought it was hard to tell if the brakes were bled good or not when the car is off because of the whole stiff pedal thing after one or two pumps due to no vacuum draw on the brake booster.

so yes, try bleeding them with the car on. that is how i do it, and have never had any problems with mine (that were related to bleeding lol. i have had a line blow out that should have been replaced 5 years ago, and a caliper get stuck, but that was because i believe it was 19 years old)