Rubish brake pedal...

[stevespic]

Hi, Guys.... i have had the great pleasure of replacing the discs, pads and front flexi hoses on my S2 this weekend... What a NIGHTMARE ! after having the problem with the pad plates and then after dealing with nearly everything which needed undoing being sized up i finally got the job done, i then used the pressurised system for brake bleeding witch seem to have removed the air a treat, BUT after i finished bleeding the brakes i had a good pedal... but after driving the vehicle home i can only get a good pedal after pumping it once or twice, i wasn't sure if this was down to the car having new discs and pads so i bedded the brakes in over a 30 mile drive which included some quick stops, once i have pumped the pedal and i get a hard pedal the brakes are A1... is it possible i could still have air in the system and should i bleed them again...? []

 

[stevespic]

1. 944 Turbos, 944 S2, and 968s there are two bleeders on each caliper. Bleeding should be done separately through each bleeder on the caliper... Just read this on another site dose anyone know if its true ..?

 

[random hero]

What are the rear flex-hoses like as i had a soft pedal caused by a perished rear hose !!

 

[stevespic]

The rears were ok but badly corroded so i didn't change them as i would of had to change the hole brake pipe and i would still be there now...before i changed anything i always had a good solid pedal...

 

[Riverside]

ORIGINAL: spic01 944 Turbos, 944 S2, and 968s there are two bleeders on each caliper. Bleeding should be done separately through each bleeder on the caliper... Just read this on another site dose anyone know if its true ..?

Yes you need to bleed all eight. Each caliper has one on top of each half, inner & outer.

 

[stevespic]

Ok, so it looks like my nightmare continues... Now i have been driving the car will i have to bleed all eight again or can i getaway with just bleeding the four which i have missed ?

 

[Riverside]

ORIGINAL: spic01

Ok, so it looks like my nightmare continues... Now i have been driving the car will i have to bleed all eight again or can i getaway with just bleeding the four which i have missed ?

I would. It doesn't take twice as long to bleed both nipples at each corner. Twice as many chances to shear one off though []

 

[stevespic]

When i bleed all eight should i bleed the two on one calliper one after another or should i bleed one at a time on each corner and then carry on and do repeat the same on the other nipples on each corner [X(] ?

 

[Riverside]

ORIGINAL: spic01

When i bleed all eight should i bleed the two on one calliper one after another or should i bleed one at a time on each corner and then carry on and do repeat the same on the other nipples on each corner [X(] ?

Each caliper has one brake line going to it, this line is screwed into the inner half of the caliper and feeds the inner two pots directly, and the outer two pots via a short connecting pipe (visible beneath the caliper). Think of the path for the brake fluid inside the caliper as a U shape with a nipple at the top of each side.

To get any air out of the brake line between the master cylinder & the caliper you can use either nipple, then once you've done that bleed the other nipple on that wheel to clear any air out of the bit of the U that was missed by the other nipple.

As a general rule always bleed from the longest line to the shortest line (from master cylinder to nipple) so start with OSR, then NSR, OSF, NSF, doing both nipples on each wheel before moving to the next.

 

[stevespic]

Thanks for that info...I will give it a whirl tomorrow...

 

[Hilux]

And when you`ve done it, do it again. You will get more out the second time.

Its a bit time consuming but better time spent now than barreling down a road with potentially no brakes after a hard stop attempt.

 

[zcacogp]

A bit of advice I have read (but can't vouch for) is that sometimes you can get small air bubbles trapped in the caliper which can affect things. A good 'thump' on the caliper while bleeding will dislodge them - they will come rushing along the bleed tube.

If you have a pressurised bleed system then bleeding the brakes isn't a hard job. Are you sure that the fluid you have put in is decent (i.e. new, and hasn't been sitting in a damp garage for the last decade or so)?


Oli.

 

[morris944s2john]

You have you bleed both sides of each callpier, so yes, all 8 nipples! I did this last year when I refurbished the front callipers and got a great pedal after that.

 

[Neil Haughey]

ORIGINAL: zcacogp

A bit of advice I have read (but can't vouch for) is that sometimes you can get small air bubbles trapped in the caliper which can affect things. A good 'thump' on the caliper while bleeding will dislodge them - they will come rushing along the bleed tube.

If you have a pressurised bleed system then bleeding the brakes isn't a hard job. Are you sure that the fluid you have put in is decent (i.e. new, and hasn't been sitting in a damp garage for the last decade or so)?


Oli.

I have a Sealey pressure bleeder, it is one of the ones you have to pump up rather then the ones which are fed from a workshop supply. My question is do I need to push the pedal afterwards as well? I have conflicting advice on this one, some say you still need someone to help press the pedal and do it all again after pressure bleeding some say the pressure bleeder is all you need.

 

[zcacogp]

ORIGINAL: Neil Haughey
I have a Sealey pressure bleeder, it is one of the ones you have to pump up rather then the ones which are fed from a workshop supply. My question is do I need to push the pedal afterwards as well? I have conflicting advice on this one, some say you still need someone to help press the pedal and do it all again after pressure bleeding some say the pressure bleeder is all you need.

Neil,

Strictly speaking, no you shouldn't have to push the pedal if you have a good pressure bleeding system such as you describe. Pusing the pedal generates pressure to push the fluid through the system, but this isn't necessary as you have the pressure reservoir instead (i.e. the thing you have pumped up.)

HAVING SAID THAT, pushing the pedal for the final bleed on each nipple may not be a bad thing to ensure that there are no errant bubbles in the master cylinder. (But I didn't bother, and it seemed to work fine.)

As an aside, when I bled my brakes after rebuilding the rear calipers, it seemed to take a good few days before they settled down. What was doing this 'settling down' I'm not sure (it may have just been me), but they seemed nothing more than 'OK' when I had done the job, and I earmarked it to do again the following weekend, but 3 or 4 days later they were really very good so I didn't bother.

Make of that what you will.


Oli.

 

[stevespic]

Job Done Thank the Lord...After my first attempt of cracking off one of the rear inside nipples and shearing it straight off (even though i was working it on and off slowly with the free off spray...)I have to say i felt sick because i wasn't sure if it had opened or not ? (there goes my weekend at silverstone.)..luckly it was closed and after testing the brakes numerous times i was sure it was not releasing any fluid but had to reside to the fact that i could not bleed that side of the calliper...Anyway my mate who's garage i was using kindly opened the rest of them for me by bouncing a hammer of the top of the nipple and gently cracking it off at the same time with a spanner, anyway i used the one man brake bleeder so i didn't lose any fluid along with the pressurised bleed system which also had a bottle with the fluid in and then screwed on top of the brake fluid res taking the air from the nearest tyre... this worked a treat, the pedal is nice and firm and after replacing the discs,pads for EBC yellows and adding super blue its braking like a new car...Cheers for all your advice, it was a great help. Steve.[][][]