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Brakes.. Too soft?

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Old 09-03-2004, 01:10 PM
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Default Brakes.. Too soft?

Whenever I hit the brakes, it feels too soft.

On the highway, during over 60~70 miles, when I push the brakes, it stops and works immediately, but, when it slow on the local, I should press harder and deeper.

Interesting thing is that when I hit the brakes, it reduces the speed and the pedal starts to go down. I mean once I press the brakes and reduce the speed, I have to keep pushig harder and deeper, and the pedal goes down gradually.

Is it something wrong?/ or normal?.
Old 09-03-2004, 01:13 PM
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When was the last time your brakes were bled? Are your calipers or rear brake cylinders leaking? What about the master cylinder? Is the reservior properly filled? What does the fluid look like?
Old 09-03-2004, 05:57 PM
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yeah it sounds like good ol' spongy brakes which shouldn't ask for more than a fluid bleed.
How long since last brake job?

mike diaz
Old 09-03-2004, 06:53 PM
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Hoses.
Old 09-03-2004, 11:01 PM
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Default brakes job,

It was last year that I bled the brake fluid.

I very often check the reservoir and fluid level. It seems ok to me and no leaking at all.
It'* been almost two years with this symptom.

When I stop at the traffic light, to remain the car stop, I have to press the pedal deeper and deeper. I can stop the car by pressing slightly, but after that, I have to push deeper and deeper..... Or, I have to off the pedal and push it again...

Is it urgent?.
Old 09-04-2004, 01:14 AM
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I can't say that it is or isn't urgent (since you know how hard is to get it to stop and not me) but that post above does bring up a good point about brake hoses.
Stock rubber hoses which go from caliper to the steel brake line in the enginebay eventually wear out and start to expand some each time you apply pressure (i.e. when you brake) which makes it require more pressure to keep applying your breaks.

The hoses should be about ~15.00 dollars (us) a piece from a chain parts store, obviously more if you go to the dealer. You might try looking into braided steel line (which lasts a whooooooole lot longer cuz the steel doesn't ever expand like rubber) but i'm not sure where you can find some of those.

If i were you i'd check those hoses and see what they are like, i just changed mine because there were slits in the rubber part on both front hoses (inside the rubber portion there is a second portion but i wasn't going to wait till that cracked too).

Anywyas take a look, if they look worn out, just replace em... i guess it'* hard to know if they're worn out by looking, any idea if they are the original ones or not?

mike diaz
Old 09-04-2004, 05:03 PM
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Pop the tire off and have someone push the brakes very hard. Expansion over 1/8" in diameter is out of compliace and warrants replacement.
Old 09-04-2004, 06:09 PM
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If the pedal slowly needs to be pushed further and further, it could be the master cylinder going bad. I had a similar experience.
Old 09-04-2004, 09:59 PM
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I agree with jwickoff99.

The symptoms you describe are exactly what happens when the rubber cups in the master cylinder piston begin to leak. As you press the pedal, the master cylinder piston pushes fluid through separate passages to the front and rear brakes. When the cups on the piston begin to leak, fluid on the high pressure side leaks past the cups back into the reservoir causing the pedal to slowly go to the floor as you maintain pressure on the pedal. This fluid under a couple thousand psi, can quickly turn a little leak into a bigger one by cutting a groove as it squirts past the edge of the rubber cup(*). Typically, you can release the pedal and press again to maintain pressure in the lines. This is "pumping up the brakes." The reason you notice it more in town is because you have to hold the pedal for a while at a red light or stop sign. On the road you typically only have to brake for a few seconds to slow down.

Replacing the master cylinder is a pretty easy and inexpensive job. Make sure you "bench bleed" the new cylinder, and fill the reservoir before you put it in. Don't let the reservoir empty as you are connecting the lines, or you will need to bleed the master cylinder again.

You will want to bleed your brakes after you get the new master cylinder installed.

Good luck.
Old 09-06-2004, 02:38 AM
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Default Bench Blend?.

Please tell me more about the Bench blend?.


the manual says,

1. secure the master cylinder in a soft jawed bench vise,with the frond end slightly down'
2. ...

..
it seems that I need a spcial tools. Is there any better way to do this without special tools?.

By the way, Do I have to really replace the master cylinder?...
It'* been almost two years...


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