Brake line is not bleeding

JYOUNYA1 · Post by **JYOUNYA1** » April 9th, 2006, 12:51 am

Replaced my Rotors today, and notice that my passenger rear brake is not engaging...when I change my pads today...I notice that the passeneger rear pads were almost new looking...so I tried to bleed the pass. rear brake line and nothing came out...nothing at all. I put a new boot on the caliper pistion...and the caliper moves and functions properly.

PATDIESEL · Post by **PATDIESEL** » April 9th, 2006, 1:53 am

Check for a pinch in the line. It could also be that the proportioning valve is messed up, but I doubt that.

JYOUNYA1 · Post by **JYOUNYA1** » April 9th, 2006, 4:03 pm

Thanks Pat...I checked the lines, and no pinches...I followed the lines and it looks like it may be the Dual Proportioning Valve...if it is what do I do, IUm guessing it may be cloogged...I checked the other brakelines and they are bleeding properly? Disconnecting the lines there is gonna put alot of hir in my brake system. What would you suggest?

~Jay

PATDIESEL · Post by **PATDIESEL** » April 10th, 2006, 12:42 am

Try taking the line off the caliper first and see if it will bleed straight from the line. If so then you know it is the caliper.
I honestly cannot see the lines getting clogged. Someone would have to have let something go into the master cylinder without the filter basket on it. That would be (A.) be stupid and (B.) a difficult thing to do.

Changing the proportioning valve is not easy as the lines are hard to get to. The valve is also expensive and only Mazda has them that I know of. You might try RockAuto.com they have alot of MX-3 parts at good prices.

JYOUNYA1 · Post by **JYOUNYA1** » April 10th, 2006, 1:33 am

Hey Pat, today I did as you ask...I check the caliper and is moving fine and not seized at all...so I disconnected the brake line from the caliper and had my roommate press the brake a couple of times and no fluid what so ever came out...so I followed where the rubber hose meets the metal tube, disconnected it, pressed the brake pedal and nothing again...I followed the metal tube to a knuckle/elbow...disconnected it from both side, pressed the brake pedal and nothing....from this point I think the next stop in the brake line is the Dual Proportioning Valve...and like you said it looks real difficult to inspect...I managed to get a wrench in to loosen the line for the pass. rear brake, and then realized if I dissconnect it, it's gonna be a pain to reinstall, cause it was getting dark outside. After work I will disconnect the line from the proportion valve and see if fluid is getting to that line.

JYOUNYA1 · Post by **JYOUNYA1** » April 17th, 2006, 11:23 am

Hey Pat, i didnt get a chance to play with the Dual Proportion valve...but the car is running ok...Here is the new delima...I have replaced my stock rotors with Brembo Slotted and (get this) Dimpled rotors...Slotted in dimpled my drill holes don't gp all the way through...I get this weird nose coming from my Rotors while driving sort of like...have you ever heard the noise that bugs make on a real hot day...its similar to that noise (like a extremely fast high pitch rattle or scratch), is this normal on drilled(dimpled) and slotted rotors...I mean the car stops and goes fine with the exception of the passenger rear.

PATDIESEL · Post by **PATDIESEL** » April 17th, 2006, 9:08 pm

Do you have the brake clips on? It is probably a pad bouncing off the rotor and you hear it hitting the slots as they pass by.

If you don't have the clips you can buy them from Mazda or Napa carries them also I think. They are cheap from either and should stop that chirping. The brakes will make more noise as you brake, but that is to be expected.

Did you ever get the rear lines to bleed?

That was a strange problem if I've ever heard one (wierd)

JYOUNYA1 · Post by **JYOUNYA1** » April 17th, 2006, 9:46 pm

I havent been able to make the pass rear brake line bleed...there may be a clog between the DPV, and the knuckle connection under the gas tank...a friend said I should be able to run air into the line...I cant see how all three brakes can be bled except the pass rear...

Oh yea, scary story...I am coming from my friends job and my dirvers caliper comes off while driving and gets lodged between the rotor and my rim, praise God that the rubber line didnt brake.a md everything is in tact...it was probably my fault rushing the rotor swap so I could get to work...but that day I took my time and inspected each brake line and re bled them,a nd made sure everything was tight.....phew....

any ideas as far as blowing air in the brake line?

PATDIESEL · Post by **PATDIESEL** » April 18th, 2006, 1:52 am

Air will not produce any force that the master cylinder cannot. (it may even blow the line so I would stay away from it) Besides how would you hook the air line into the brake line so that you are not loosing air around the connection?
As for the one brake not bleeding; You disconnected the lines and it will run fluid to the back, but not through the one caliper? If so I'd say it is the bleeder or the whole caliper. Take the caliper off, take the pads off, run the caliper piston in and press the brake a few times. Does the piston come back out? Is the wear on the rotor even? If all that is yes then jsut replae the bleeder. If not replace the whole caliper.

JYOUNYA1 · Post by **JYOUNYA1** » April 18th, 2006, 9:55 am

Well I mean I totally took off the rear caliper(disconnected it from the brake line). I pumped the brake and nothing came out the rubber line that connects to the caliper. I then disconnected the rubber line from the metal line...pumped the brake a couple of times and no brake fluid...now...between the connections of the rubber to metal hose and the metal hose to the first connection knuckle, there is a slight pinch in the plastic shroud, but doesnt look to have damaged the metal portion of the line...I disconnected both sides of the first knuckle and no brake fluid...so regardless of pinch or not it still should have show a slow of fluid...

As far as the brake noise is due to no brake shims (the slim back plating that goes on the back of teh brakes). Because my new brake pads didnt come with new shims, or is there something else you are talking about?

Thanks

~Jay

PATDIESEL · Post by **PATDIESEL** » April 19th, 2006, 3:54 am

No I guess I misunderstood one of your earlier posts. I cannot honestly say why in the hell it would not be getting fluid at least to the end of the metal line. (unless it is a blockage or bad proportioning valve)

Man what a PITA this is going to be to fix. You really need to find and fix it though. An emergency brake with only one rear pad working will cause you to loose controll quickly.

I would suggest jsut going to a J Yard and getting the whole rear brake line and prop valve. Then at least you have all the pieces to replace whatever it is that is messed up.

JYOUNYA1 · Post by **JYOUNYA1** » April 19th, 2006, 9:33 am

Right...when I get a change to go back to pull-a-part, I will get them...in your opinion do you think I should get both rear lines or just thr troublesome one?

The ebrake works of course because it's cable operated (of I knwo you know this), and I have tried pulling and releasing the E-brake like crazy hoping it will build pressure free up what ever it is that is not letting that brake line fill with fluid to the caliper, but that didnt work.

I probably will have to wait until next weekend to get those parts...I have military duty this weekend....I am strickly driving to work and back and thats it.Anyway I will be sure to keep you updated.

Cy · Post by Cy » April 20th, 2006, 12:38 am

If you pump the brakes with the rear lines uncapped.. they will suck in air ... the lines are long enough that they produce enough or not enough force that it doesn't open the valve in the master...

I had the unpleasentry of fixing a guys GS so he could drive it 200km to sell it...Back flex lines were exploded from rot.. so i capped them both off and bleed them both using the cap nut as a bleed screw..

a couple times because the nut wasn't on tight and if sucked in air.. and when my buddy pumped the brake again it wouldn't have ANY pressure..

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When you disconnect the lines from the calipers they WILL drain.... either taking the whole master cylinder resivoir with them or just the fluid in the lines..

you HAVE to bleed them out with the bleed screw and preferably with the car running to get the advantage of the brake booster...if you disconnect BOTH of the rear rotors and all that fluid drains.. then it will take you filling the resivoir back to the VERY top and then bleeding 1 side and then filling it again because it will be at the min level... then bleed the other side.... then fill it then bleed the clutch... then do ALL the brakes all the way around...
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Buying a few 1l jugs of fluid is better because once you open a bottle of fluid it's chemically useless as brake fluid after 2 months (too much air in it = brake fade)...

JYOUNYA1 · Post by **JYOUNYA1** » April 20th, 2006, 1:50 am

Thanks

WHoa...I didnt think about bleeding the car while the engine is running, for the extra boost pressure...I hope and pray that can fix it...i have two bottle of DOT 3 Brake fluid...

So tomorrow after work I will
A) Unscrew the bleed screw with the engine running and pump the brake to see if fluid flows with assistance form the booster...

B) As for the brake noise on my new cross drilled and slotted rotors, I will install some brake shims to see if that fixes the noise...

C) (off topic) Pat I still need to get back to you on those autometer gausges I have...I am gonna find a different wiriing path for them and give you a personal made diagram...I will post it in the original forum we dicussed it in.

Cy · Post by Cy » April 20th, 2006, 2:13 am

not just unscrew and pump...you need 2 people... or a 1-man bleeder...

you have someone PRESS the brake pedal.. then when they do that you open the screw and you close it as soon as it stops coming out(lightly though.. not 3 turns after snug) the whole time your inside the wheel well they're pressing down HARD on the pedal...then after it's tightened down they let up..

basically same as bleeding but your bleeding air, atleast until the fluid makes it down the line... then do the clutch... then do all the lines again...

there's a FAQ on the order .... but i start rear pass, then rear driv, then front drive then front pass... if it's still squishy i start @ the rear again...