lkailburn

Looking for help troubleshooting which part is faulty here.

Car is a 97 civic dx. already swapped on 10.3" and milled ITR calipers up front a few months back. Just did a GSR rear disk swap, started to bleed the system then decided i better swap in my new MC and booster. 1" gsr MC and booster from a 94-97 integra gsr ABS model. (does abs vs non-abs matter?).

i do the booster/MC swap, run new lines to the mc and bench bleed the MC. Now, bleeding the calipers in the proper sequence starting at RIGHT REAR. bleed it out like 15 times bubbles here and there then no more bubbles on the last 5 bleeds. good, so i move to the FRONT LEFT. bleed out bubbles on the first few, then no more bubbles on the next bunch.

<u>HERE"S THE IMPORTANT PART</u>
Then i move to the LEFT REAR. my dad says "hm your pedal is WAY at the very top". he holds the pedal and tells me to open the bleeder. i open the bleeder 1/4 turn and he says "the pedal is not going down at all?". i close the bleeder we try again. same thing pedal doesn't go down. then we hear a loud POP and the pedal falls pretty easily to the floor. i close the bleeder and we try to maybe bleed it again. this time the pedal sinks fast and practically no fluid or air comes out the bleeder valve on the caliper. try two more times nothing. theres no pressure getting to the back.
I test the pedal out myself and theres a bit of resistance on the pedal, it does always come back up to the top, but you can still easily hit it to the floor.

Today i read Helms and Haynes and did some tests on the booster:
--I checked the booster vacuum line by removing it from the booster and starting the engine. the line has PLENTY of vacuum so it seems the check-valve booster line is good.
--i held the brake pedal and started the car and the pedal did sink a little. but it was also VERY VERY easy to put the pedal to the floor.
--i turned the car off and pumped the pedal a few times, it would build up to the VERY top. so basically there was no travel in the pedal at all. if i hold moderate pressure on the pedal, it did seem like it would eventually sink down a bit.
--I visually checked MC, Propvalve and four calipers, i'm not leaking any fluids and the resevior level has not gone down.

SORRY FOR THE LONG STORY.

What do you guys think is the problem? Bad MC or bad booster?

Thank you!!!
-Luke

BrakeExpert

its possible that the diaphram in the brake booster went bad or the 'stick' on the master cylinder bent. I've never had this problem. Bump for answers.

cxSHOE

abs has no bearing on your upgrade, i use a '99 ls abs 1" m/c and booster, no problems, in a non abs car.

as far as the "pop" check to see if the clip on the rod is still attached, you'll have to look up from the floorpan area of the drivers side.

when i did my swap, i also have to entend the rod for it to activate my cruise control brake sensor (incase you have problems with your cruise control)

bleeding the brakes from front to rear...doesnt matter where you start as long as you get all the bubble out. most will say it does and even the helms says to do this way, but unless you take the time to test if it does matter you will just follow what everyone says and you will never know for sure.

but check the small clip on the booster (the rod that pushes into the back side of the booster) follow your brake pedal to the brake arm all the way to the clip. you need to be upside down with your head on the floor, unless you have a long kneck. lol

lkailburn

both haynes and helms post the proper bleeding sequence as RR, LF, LR, RF. might as well do it in the correct order no?

anyways, i'm not entirely sure which clip you're talking about. the pin that connects the booster to the pedal?

here's two pictures of how everything is at the moment.





-Luke

lkailburn

up to the top for quick help!

UPDATE: I removed the master cylinder and bench bled it again. after a few pumps (6 or 7) the lines were clear of bubbles. its not leaking anywhere. and both ports seem to be pumping out the same amount of fluids. anything else i should do with the MC to test its functionality? block off the ports and push the rod to see if its bypassing internally?

-Luke

lkailburn

Hey Mike (brakeexpert),

what are symtoms of a brake booster with a blown diaphram? during one of my tests, i had the engine running and when i fully depressed the brake pedal the idle would fluctuate. then return to normal when i let up on the brake pedal.

-Luke

lkailburn

bump

so lazy

i've had this problem before on a customer's car.. he just replaced his MC and bled it the same way you stated. well i pulled the car into the shop bled it myself and i ran into the same problem as him. after 10mins into this i had a co worker pump on the brakes.. and i sprayed like soap and water between the MC and booster where the MC is mounted on the booster where the 12mm bolts are. well i figured out there was AIR coming out between there. he didn't tell me there was a gasket there before.. it great to work behide people.. also the car was a 96 gsr with abs.. good luck hope this helps you

i usually dont post here but thank " rnp007 "

so lazy

also not to be a JACK but that MC doesn't look new.. nor does the booster..

lkailburn

thanks for the input. are you talking about this gasket?



-Luke

so lazy

nope.. thats a seal.. the gasket is around that and sits back to the MC.. but i just found out this is not a new MC.. i acutally made it cause the guy was wanting it done that day.

lkailburn

hm i didn't know there was supposed to be a flange gasket. a gasket that matches the 2 bolt flange on the mc?

-Luke

serio_ENDLESS

i thnk this is not possible ive had a 95 civic and tried using a 96 gsr mc it didnt work do to the fact civics usually come without abs 4 dr models comes with abs

lkailburn

serio-endless --- i've had multiple people confirm that it IS possible to run abs MC/boosters on non-abs cars

-Luke

marshun

i thought the abs MC had extra **** on it. oh well.

it sounds like yer booster is done.

lkailburn

marshun i wish i had more knowledge myself. (i hate playing he said/she said) but i can't find any exploded diagrams or blue prints of either model. all i know is a few people (reputable guys i might add, such as a well known 'brake expert', and a honda certified engineer) agreed that it was possible to run either on a non-abs car.
have you first hand experienced a bad booster? any clear cut indicators? when people say their booster went out they usually say that braking the car is VERY hard. aka they basically have manual brakes and no longer have the vacuum assistance of the booster. i don't have this at all. my brakes are assisted by the vacuum. my problem is i can just push the pedal to the floor and get hardly any pressure to the calipers. (this is confirmed on the rears as they are still on jacks. i spin the tire and hop in the car with it running and it takes me about the time to bottom out the pedal before the wheel slowly stops)

-Luke

BrakeExpert

Let me clarify something. ABS is a separate unit in the engine bay. On some hondas, it will affect whether or not it has a proportioning valve. Some cars simply have an "H" turned sideways on the firewall, which simply lets fluid to the ABS unit. THe ABS unit does everything and has the proportioning set.

ABS seems to be used with our civics to IDENTIFY the master cylinder dimensions, whether or not the two ports are on the same side. Cars equipped with ABS have one shape, cars without it may have another shape. However, the ABS unit is downstream and has no affect on how the MC works. Remember, ABS is a series of pistons and **** that backs off the brakes to stop the wheels from locking, so you may feel the pedal stiffen at a certain point. but this is via the fluid pushing back FROM the ABS unit. The internal mechanics of the Master cylinder on any honda are all the same, two internal plungers and two outlet ports. The master cylinder and brake booster from any ABS car can work on any non-ABS car or vice versa. The hardlines may or may not line up, so they would have to be bled. Talking ABS may just mean the hardlines are in one spot, and thus makes it easier to select an MC since no bending is required, which is easier for a lot of us.

ABS does not 'affect' the brake booster or master cylinder on our civics. the only reason ABS is talked about with the master cylinder is because that particular ABS-equipped car may have a different shaped MC, so it is for identifying which MC is which.

lkailburn

OK. rebench bled the MC. with a better setup that did not allow any air back in. i realize now the old bench bleed setup did allow the suction of a few air bubbles back into one port on the MC.

-regreased the piston on the MC, the seal, and the rod on the booster
-reinstalled it on the booster. double checked torque specs for MC-booster
-cleaned out the resevoir basket (it now had rusty particles inside the basket. ??) topped off fluid.

to eliminate any chance of somehow super offsetting the chambers of the mc we only bled each caliper about 5 times. last time we started off fully bleeding the line (15-20 on the rear). we successfully did the RR, and then the left front again. now we were at the left rear. the same place it went POP last time. we start off bleeding and have LOW pressure. hardly much coming out the bleed line. on the 3rd bleed i feel a big wiggle in the bleed line and then BAM we have full pressure again!! bleed about 3 more times. good solid pressure.

we finish the sequence. top off the fluids again and went all the way around successfully a second time, still only bleeding about 6 times on each caliper. i think i might run the engine and see what i feel. if all is well i'll do a full bleed.

what do you guys think? particles clogging the propvalve? something weird like that?

-Luke


Modified by lkailburn at 10:19 PM 1/22/2008

lkailburn

well.. bled the car until there was nothing but brand new clear fluid coming out the end. kept testing the brakes with the engine on and off. pedal felt normal. but possibly a bit low and still perhaps a bit squishy. not sure if i'm paranoid now or what.

dropped the car off the blocks and took it around the blocks and parking lots. i don't know what else to say but... it works? brakes are working, ebrakes are working (might need a bit more tightening) but all in all...everything seems to be working? the pedal may be a bit low and squishy. could this be attributed to shitty *** old rusty rotors in the back? i used the ones that came with the swap.

as you can tell i'm still cautious about it all. i'll do nothing but drive it around just the closest blocks before i have full faith in the brakes.

thanks for everyone's help. post up comments thoughts etc please

-Luke

BrakeExpert

The feeling bleeding the 3rd caliper is normal. See Honda uses a crossed brake system like many cars do. There are 2 ports on the MC. the fluid from each goes to one front and one rear brake, one left and one right. So one port controls the RR and FL while the other controls the FR and RL . You bleed the RR and FL brake and that sort of 'fills' that part of the hydraulic system. The right rear is one of two on the new area where you had no fluid before. Its not until you bleed the last brake that the pedal will firm up noticably.

Your brakes should feel spongy and have a long stroke right now because you are using old rusty rotors. The pad and rotor are not in sync, meaning the contact area is low. remember, the edges are jagged (we're talking fractions of a millimeter) but after say 200 miles of running used pads and rotors, they will bed into each other and your hard stops will suddenly feel like type-R sized brakes.

SInce its so damn cold, you could drive around with one foot on the throttle and another on the brake lightly. do it for maybe 5 seconds then stop, you don't want to fade the brakes. i don't know what pad compound you have so you don't want pads glazing.

lkailburn

dude you are the **** haha. thats exactly what i was thinking. the rears just need to bed into each other. i sanded the heck out of the rotors and even the pads, removing almost all the surface rust and cleaned em up. i figured they'd need a few miles to grind into each other.

It is freezing outside, i was freezing my *** off being out all night. it JUST snowed when i went driving so i was on an inch of fresh powder and it was super easy to lock up the tires.

but i'll let you know how it feels after some miles.

One of the good results from me working on a project is i always make a writeup so here it is:


"How to Swap your Brake Master Cylinder and brake booster"

http://www.lukekailburn.com/boostermc.html

-Luke

-Luke