brakes feeling weird.

[redmugenjazz]

hey oz hondars' i would need some of your help on this one i;ve just replaced the brake pads on my front wheels (disc brakes) and went for a test drive down my street, i've noticed that the brake pedal stroke is alot longer than the old ones. Is this normal or am i just noob and didn;t install the pads correctly??

[OMG.JAI xD]

did you pump the brake pedal after you pushed the caliper piston in?
if there sufficient brake fluid in the resevoir?
did you perform a bleed after the pads were replaced. if you did, maybe check that the bleed nipples are done up.
if you didnt, maybe it is a good idea to bleed the system, if its feeling a bit spongy.
check that you didnt kink any brake lines, hoses, check for leaks if you have.

either that or you just start noticing the brake pedal sicne you just replaced the pads. its a mental thing. you start paying more attention to something that just got replaced to try and point out a fault.
check the above and come back to us. =]

[aaronng]

Did you use OEM pads again or did you go aftermarket?

[redmugenjazz]

did you pump the brake pedal after you pushed the caliper piston in?
if there sufficient brake fluid in the resevoir?
did you perform a bleed after the pads were replaced. if you did, maybe check that the bleed nipples are done up.
if you didnt, maybe it is a good idea to bleed the system, if its feeling a bit spongy.
check that you didnt kink any brake lines, hoses, check for leaks if you have.

either that or you just start noticing the brake pedal sicne you just replaced the pads. its a mental thing. you start paying more attention to something that just got replaced to try and point out a fault.
check the above and come back to us. =]

good, point. but lol i think my procedure is incorrect, i didn't touch the brake fluid resevior at all so no bleeding was done. the brake fluid is still full despite a slight leak when i tried forcing the piston in on the right hand side caliper. But woundn't i need to replace the fluid if i bleed the brake fluid. btw i got the bendix pads from autobarn.

[OMG.JAI xD]

well you dont need to replace brake fluid when you change your pads and/or discs, it is recommended though, but it depends when you last got your brake fluid flushed. which is an interval of once a year at least.

and taking 'aaronng' 's comment. reason why he asked which pads you got is, aftermarket pads might have less meat on em. (brand new). hence the longer stroke feel.

try without the car running. pump the pedal afew times.
soon as you start the car first time you pump the pedal will go to the floor. or nearly to the floor. thats normal. once u pumped the pedal with the car off, with the car on pump the pedal slightly, just a touch each time (youll hear that sssss ssss sound from the brake booster), till you feel a pedal. if the stroke is still the same then itd have to be the pads.

long story short. if your car stops. then its all good. lol

[redmugenjazz]

yea, i agree, the pehdal goes stiff when i pedal the brake when the car'f off. when i turn it on, the pedal goes right to the floor. i did what u sed, pumped it heaps of times but lol, still goes to the floor. when the car;s on all i hear is a whoosing hydraulic sound from the brake piston (this was after i changed to the new ones). B4 with the old pads, (their worn to half the depth of the new ones) it only took say max of 5 cm pedal stroke to apply full brake force. now, with the new pads its all the way to the floor. wtf eh? you think i screwed up my cailipers.? thnx dude

[JohnL]

With your old pads, it sounds like the pedal motion was already excessive (5cm pedal motion is too much with four wheel disc brakes, about what you'd expect with rear drums in need of some adjustment), so you may need to bleed them.

With new pads the pedal can feel soft until the new pads bed in to the rotor surfaces, i.e. the new pads will be nice and flat, but the rotor surface may not be, and the pad material that is touching the high spots on the rotor will compress as the piston pushes against them, then decompress as the pressure is released (pushing the pads away from the rotor in the process).

The problem is worse with rotors that are worn with grooves etc, but gets better as the pad wears into the uneven rotor surface and the piston pressure can then be applied over the entire pad area rather than just a small % of it. When this problem exists, the brakes are far less effective in hard useage until the pads bed in, so be careful.

Your pedal going all the way to the floor after you fitted new pads may be a combination of gas in the hydraulics, and un-bedded pads.

[redmugenjazz]

Hey i bleed the brakes today in response to jai's and jonh's recomendations, it really helped, the pedal strokes is similar to what it was before i changed the pads, however, the brake pressure does seem a little uneven during hard braking. So i guess i just have to wait till the pads 'bed' in to the uneven rotors.

[JohnL]

Try to avoid hard braking until the pedal firms up (i.e. pads bed in). Before they bed in you're effectively braking with a smaller pad area, and so X heat is going into a smaller surface area of the pads.

If you brake hard, you run the risk of overheating the surface of the pads where they are heavily contacting the rotors, and you may glaze them more easily than with bedded in pads, not to mention that the brakes just won't be as good until the pads bed in.

[55EXX]

sorry for the mini thread hi jack but what does it mean when you are able to push the brake pedal in so it cannot be pushed further, eg waiting at lights, but then if you continue to push it , eg still waiting at those light, it slowly sinks further and further down.

[aaronng]

sorry for the mini thread hi jack but what does it mean when you are able to push the brake pedal in so it cannot be pushed further, eg waiting at lights, but then if you continue to push it , eg still waiting at those light, it slowly sinks further and further down.

How far down does it go down? All the way to the floor?

[Joe kickarse]

Sounds like a leak?