Need help diagnosing a brake problem – mz11

[Johnzoku]

sorry for the noob question. but you guys are good at helping me out in times of need

Recently I changed the front pads so I thought id change the rears to the same brand as well. All went smooth and the new pads went in a treat. Then I went to bleed them and I started by bleeding the longest line… no worries there. Then I went to the other side and bleed that… I couldn’t get rid of the bubbles. So I tried to bleed the brake master just like TSRM describes, and to no avail. I got the GF to pump the breaks (which was a problem in its self!!!) and all that was happening was little squirts of brake fluid and no change in the pedal.

I went back to TSRM and the trouble shooter says for “hard pedal but brakes inefficient” – piston frozen in caliper, brake booster faulty, vacuum leaks, or brake line restricted. Now since I tried to bleed the master cylinder im guessing it’s a faulty brake booster.

So my question I guess is, is there a way to know for sure (or did I already find it) and is there anyway around having to remove my brake booster/getting it rebuilt? Or even a replacement one I could use in its place?

i was hoping for a quick fix because i FINALLY got my RWC and then this happened!!! eRRR!!!

thanks.

[Major Clod]

Hey dude,

Just checking some pretty basic stuff here but might as well ask. She was pumping then holding while you opened the valve, and didn't release the pedal till you had tightened it up right...? Also made sure that the master cylinder was kept topped up with fluid throughout the process?

Ryan

[Johnzoku]

to tell you the truth, im pretty sure i told her what to do and im pretty sure she didnt do it... so i think she was pumping the brakes while i was bleeding them, which could be the source of my problems... dont get for GF to help you!!! hahahha

but the fluid didnt go to far under min while i was doing it...

p.s. i looked in my spare soarer and i dont have that spare mirror control but i bet you got something going by now anyway.

[Major Clod]

If ya need a hand on the weekend or something give me a yell dude... I reckon I can find a vacuum pump in the shed so we might not even need to pump the buggers.

[Johnzoku]

hey sounds like a plan, tho i think it might have something to do with the lose piston stop bolt. i got a cinder block and pushed the pedal in with it and tightened the bolt and the brakes are working alot better now... so maybe i got to pull the master cylinder apart and reposition the piston again?

[Jag7799]

Sorry, I can't see whether you made clear that the brake pedal did end up going hard?
I had my master cylinder die not too long ago after I put on the skyline brakes, I honestly can't remember whether I got a rebuild or a new one, but it cost about 180 bucks - if it comes to that.
My problem was that the cylinder wasn't releasing the pressure after you let go of the pedal, so the brakes just got tighter and tighter until the stuff down there caught on fire.. haha

[Johnzoku]

yeah my brakes arnt doing that... they were jsut stoped so i think like my last post, the piston the the master cylinder has moved out of place...

so my pedal wasnt going had it jsut was hard... like 10mm movement then nothing at all... the fire was was flexing. haha

it sounded like you had a serious problem on yours... lol.

[japlish]

yeah its a mission to get my wife to help do the brakes as well
she wasn't pressing on the pedal when you were tightening the bleed valve up,was she?
cause that can make your pedal hard.

[Jag7799]

You guys are far too trusting
what happens when you're driving(probably speeding) and go to hit the breaks and she hasn't done it right and you crash into a tree?
haha

[japlish]

oh she's learning

[Johnzoku]

well it was my GF's first time helping me so maybe ill sit her down and explain it a bit better... im pretty sure she was pumping the brakes while i was bleeding them... so ithink theres jsut a mega amount of air in the lines - well im hoping anyway.

[brett_celicacoupe]

tap the callipers gently with a hammer. it can sometimes get the bubbles to move straight to the top.

then re bleed them doing it the correct way

[PT1]

get 2 helpers. 1 filler, 1 pumper, 1 bleeder. do it right. give her the pumper job. if it doesnt come right then, youve got problems.

[CrUZida]

One man bleeder kit FTW

[Johnzoku]

lol, thanks for the advice guys, ill try that hammer tap thing.

i think i need one of thoes mity vac brake bleeder kits to suck all the air out now, lol!

after much suffing around, the only problem is air in the lines, everything else works im pretty sure.