bretx0r

OK, so this is ******* killing me, and yes ive done searches i just need opinions on what is going on.

So anyways, got my brakes, got a new master cylinder and proportioning valve:

the master cylinder i got was from autozone, refurb 7/8, when i press the pedal down firm with the car OFF it doesnt sink to the ground so i am assuming my master cylinder is good.

installed the brake master cylinder after bench bleeding it until only the smallest bubbles came out (to be honest, they wouldnt ******* come out and i figured couldnt make a huge difference because they were basically nothing)... anyways, on to bleeding the brakes, so i went the standard, Left rear right rear left front right front pattern, air comes out a few initial times, then no air, move to the next corner and same thing happens. We were doing the 2 person pump method, Pumped the pedal 4 times, held it down, i opened the valve, closed it and then he released.

Once i complete all this hassel the ******* pedal is still soft, re do it again this time with the car on, same process, makes absolutly no difference.

so i bench bleed the master cylinder again i pumped it probably 20 times until i could hardly see any bubbles, hook the master cylinder back up then bled and re bled the car 4 different times and the pedal still goes straight to the FLOOR (when the car is ON). I still have brakes, but the pedal is no where NEAR as firm as i want it, and the brakes work like ****

am i doing something wrong? i mean, i dont see any leaks or anything and the brakes worked fine before the swap. Or is my impatience getting the best of me.

Hopefully someone knows what is going on because i am about to flip

john666

up down left right a b select start.
thought your suppose to start rear right then left. front right then left

bretx0r

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

i even did it in a diagonal pattern passenger rear driver front driver rear passenger front.

im_poor

how many miles on your brake booster? i just replace an integra master cylinder and came to find out the master cylinder leaked into the brake booster so i replace both with autozone rebuilt parts...

schardbody

so after you bleed it and then check it and try to bleed it again you get air again??? if you keep getting air then your MC is bypassing. other than that you can check the rear brake adjustment, if its drum brake. and check the caliper slides. also, does the pedal have no resistance at all, or does it walk to the floor kind of slowly.

bretx0r

what would be wrong if the master cylinder is bypassing? bad seals?
my brake booster has 101,000 on it

schardbody

if the booster was bad the brake pedal would be rock hard. a bad internal seal will cause the pedal to slowly drop.

bretx0r

the pedal doesnt steady drop, the pedal hardens up when the car is off (like normal) and softens up when the car is on... Is it just that i am not bleeding the brakes correctly or spending enough time with them??

Is there anything i have to do when replacing the proportioning valve? Or do the bubbles just work themselves out through the individual wheel brake lines.

pissedEK

this is very slow and messy, but I promise it works if your lazy like me, put all 4 jackstands under your ride so its off the ground and level, take your brake resivoir lid off, (this will require a costco size bottle of fluid and a couple homies mind you ) open all 4 bleeder valves as the resivior drains add fluid. DO NOT LET THE RESIVIOR EMPTY, just chill and watch it. have your homies go around and check for bubbles, when the fluid comes out in a steady stream, close the bleeders. ur good to go, NOTE: this should only be performed by those so lazy that theyve had a honda-tech membership for 3 years and posted 9 times, like, REALLY lazy.

bretx0r

bretx0r

built562

sounds frustrating to me.

it may sound stupid but did you check all the hard lines to make sure they are tight, then check the hoses and maybe replace the crush washers on the banjo bolts, then maybe inspect the calipers and make sure they are on the correct side with the bleeder nipple on top.

these may sound bumb but they are free to check.

it sounds like you did everything correct, the MC might need to bench bled again since there was air bubbles in it. also check the seal between the booster and MC and the seal of the cylinder and the MC

good luck bro, just trying to help and give you a bump

schardbody

ok, the 100% bulletproof way of singleling out the master cylinder as being the culprit: take a hose clamp *vise grip w/ rag to keep from tearing the hose) and clamp off every hose, meaning all four wheels are clamped off. now crank the car and check the pedal, if its on top then the master cylinder is good. if its still going to the floor no if and or buts about it, its bad. now if it checks out and your pedal is hard, have someone hold the pedal solid w/ car running and have someone else remove each hose clamp one by one, the pedal will drop a little with every clamp, but when you take the clamp off the problem wheel you will know it for sure. hope this helps. this is the method we use at our shop and has been for 20+yrs, it works.

bretx0r

thx for the replies

more suggestions ppl!

fast+forward

i used a speed bleeder valve (lets out air and fluid, but doesn't suck in air, all you do is pump)..my old fluid was yellow, new fluid was blue,so i just pumped until the fluid coming out of the valve was completely blue, so i was sure there was very little chance of air being stuck in the lines and only new fluid was in there...this method worked for me, but then i was just flushing the system, not replacing a MC.

bretx0r

my pedal doesnt sink when the car is OFF... does this mean the master cylinder is still good? Or does the car have to be on to make a accurate guess on that?

i hope i didnt damage my brand new master cylinder in all this madness

Cyrus4g63

may be a leak in one of the lines or the booster is bad. I just changes my booster out with an integra and the car stops on a dime.

Luserkid

Your suppose to bleed with the car on. Run the car and bleed again.

bretx0r

bump

walters474

There's probably air in the propotioning valve. Crack the more accessable flare nut, in each circuit, as if bleeding. The bottom circuit can be accessed from the bottom. Celebration time after much frustration. 96 Accord, non ABS.

Former User

9 years later? You're a little late.