Wassup guys, I had my max since july but never change brake fluid. I notice its black from wut i see. Can bad brake fluid make brakes weak bc wen i step on my pedal its soft not stiff and sometimes i have to pump it and i do have ABS.

 

Air in the lines can cause this, but if it's simply old that should not cause a soft pedal on the street.

It's probably your master cylinder, unfortunately. I recommend taking this pretty seriously.

Dave

 

yeah i had the brakes done last weak, and i told the mechanic to check the master cylinder. He told me he checked it and everything is fine and jus the pedal needed adjustment. So i got the car and the brakes were great but the next day the pedal was soft again. So i will get them check asap

 

yea sounds like a leak. i would get that resolved ASAP. they could fail while youre on the highway going 75.

 

If your brake fluid is black, that means there is moisture in it. You need to flush it and put in new fluid, then take it from there. Brake fluid over time and hard braking develops moisture, therefore causing 'weak' or bad braking. I would not discredit the Master Cyl being bad, or a leak/ air. But black fluid IS a sign of moisture, or aka old fluid. Bleed them thoroughly as I said, make sure you follow the procedure in the FSM or manual as there IS a sequence. Then take it from there.

Just for the record, most clutch fluid is the same. I JUST had to bleed my buddy's civic because of this issue. It was pure black, and from the below freezing temp lately, it froze and he had NO clutch response. After the bleed and all new fluid, it was perfect again. The fluid was 2 years old, and he road races this car in the nice months as well as DD. So it gets a lot of heavy use.

http://www.aa1car.com/library/bfluid.htm
http://www.afcoracing.com/tech_pages/fluid.shtml

 

thanks alot, will do. Im getting it done most likly today

 

in a sense, yes and in a sense ... no. old brakefluid can collect dirt and dust making it clot up. think of it like the Drano commercials .... nice new clean pipe -vs- old clogged up dirty pipe. I guess what I am saying is that it could block all of the fluid from going thru. not a bad idea at all to change your fluid if it is "black". new stuff is a light redish brown. DOT 3 or DOT 4 either one is ok ... same as clutch fluid.

better to get it fixed and not need them as opposed to needing them and not getting them fixed. or ... you can post pix after the accident

 

yeah thanks alot guys... today i was driving and i hit a bump and my brake pedal jus rattled and i lost pressure

 

If your pedal is goin to the floor when you stop then its the master cylinder. It an easy fix just make sure you bench bleed the cylinder if you install yourself.

 

jus wanted to ask guys, im taking it tomrrow to the shop to get ti checked and while its there ima tell them to flush out the old brake fluid. Jus wanted to know how much does it run to have the brake system flushed?

 

Maby 45-50 bucks.

Like previously said, over time the brake fluid collects moisture. Moisture as in water mixed with the fluid reduces boiling temp of brake fluid causing pedal fade or under hard braking maby down a hill you can loose all pressure.

 

Bleeding the system is quoted at .9 hours in a shop manual. However, because there is no flush listed it would most likely fall under how many hours it takes plus the fluid. It shouldn't take any more then 2 hours to do the whole thing. Expect anywhere from 70-150 dollars.

 

Thanks alot guys, great help

 

Find a friend with an air compressor and auto bleeder.It wont take you 30 minutes tops to do it.

OR....

If you get a shop to do it they will probably charge you around 40-50 bucks.

 

Water is just as incompressible as the brake fluid itself.

Moisture will only cause 'weak' braking if the fluid gets hot enough to boil the moisture, which is unlikely in street driving unless you're talking about a hot day, and repeated high speed stops. If this was happening, pumping the brake pedal wouldn't help.

The blackness of the fluid, as I understand it, is actually evidence of corrosion caused by the moisture. The pumping of the pedal suggests damage to the master cylinder, and in replacing the master cylinder the brake fluid would be flushed also.

It's also fine to get it bled properly and flush out the old/dirty fluid. Then if there is no improvement, replace the master cylinder. But I think changing the fluid won't be enough.

Dave

 

The brake fluid need not be flushed when you change the master cylinder, it should be, but that doesn't mean a shop will do it.

Blackness is almost always an indicator of wear. whether that be due to moisture and corrosion or wear on cylinders/seals/lines.

Have the fluid througly flushed, but as stated, this isn't likely going to fix the problem, unless of course you do have air in the system.

Also, check all lines, etc. you could just be getting air through a bad fitting/line.

keep in mind that moisture in the brake fluid does indeed raise the boiling point, but considering the time of year, it's more apt to say that it raises the freezing point, if there's enough moisture, the fluid can cavitate easily causing air pockets.