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BRAKES ARE DRIVING ME NUTS (NO PRESSURE) by antinull.com
Started on: 05-20-2008 05:18 PM
Replies: 56
Last post by: max1 on 06-09-2008 01:21 PM
antinull.com
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Report this Post05-23-2008 07:38 PM Click Here to See the Profile for antinull.comSend a Private Message to antinull.comDirect Link to This Post
this is really upsetting me does anyone have any idea what the problem might be?
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Report this Post05-23-2008 08:11 PM Click Here to See the Profile for antinull.comSend a Private Message to antinull.comDirect Link to This Post
ive adjusted the brakes as much as they will go ive replaced the master cylinder 1 hose and 3 calipers
and still nothing
WHATS THE DEAL DOES ANYONE KNOW WHY MY BRAKES HAVE NO PRESSURE?
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Report this Post05-23-2008 08:17 PM Click Here to See the Profile for antinull.comSend a Private Message to antinull.comDirect Link to This Post
im going to try putting the old less worn pads back on the rear side so that both rears have the same amount of pad.....
i have no idea if this will work
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Report this Post05-23-2008 10:27 PM Click Here to See the Profile for antinull.comSend a Private Message to antinull.comDirect Link to This Post
put the other pads on and they are rubbing HARD and still low pedal
so whats the deal? is the new MC **** ?
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chrishahn87
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Report this Post05-23-2008 10:40 PM Click Here to See the Profile for chrishahn87Send a Private Message to chrishahn87Direct Link to This Post
Just a suggestion:

Could the fluid that you're using be the problem? I know its DOT 3 (which is correct), BUT could the fact that the fluid thats being used is SYNTHETIC have anything to do with it?

I know someone is an expert out there that may be able to say if it would make a difference.
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chrishahn87
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Report this Post05-23-2008 10:44 PM Click Here to See the Profile for chrishahn87Send a Private Message to chrishahn87Direct Link to This Post

chrishahn87

1580 posts
Member since Dec 2004
 
quote
Originally posted by chrishahn87:

Just a suggestion:

Could the fluid that you're using be the problem? I know its DOT 3 (which is correct), BUT could the fact that the fluid thats being used is SYNTHETIC have anything to do with it?

I know someone is an expert out there that may be able to say if it would make a difference.


The reason that I posted this suggestion is this:
I asked an ASE certified master mechanic, who has over 30 years experience what kind of fluid to use in my truck. My truck is a 2002 Silverado, and I recently replaced the brake pads and rotors. Before I did the job (since im too lazy to check the owners manual) I asked this mechanic if I should use DOT 3, or DOT 4. His reply was: "Do NOT use DOT 4, because it is a synthetic fluid, and will make your pedal feel "squishy"." Those were HIS exact words, so dont quote me. In a way, it kinda seems like this "squishy" feeling is what you are getting, like you would have if you used "DOT 4" fluid, and according to what that mechanic said.

Good luck getting it fixed.
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joesfiero
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Report this Post05-23-2008 11:12 PM Click Here to See the Profile for joesfieroClick Here to Email joesfieroSend a Private Message to joesfieroDirect Link to This Post
Im not an expert, but I have a pretty good knowledge of physics and fluid properties. Either fluid will provide pressure to the brakes in a properly set up brake system. The difference between DOT3 and DOT4 is merely its heat and deterioration resistance. I believe all fluids react the same from a hydraulic standpoint. You put 1 PSI at the end of one hose, and you get 1 PSI at the other end. The reason we dont use water or oil or trans fluid is heat, boiling point, lubrication, etc. Long story short you should not feel a difference in the pedal by using DOT3 as opposed to DOT4. Please someone correct me if I am wrong.

That being said, I would take another look at the bleeding of the brakes. It seems there may be air trapped that is being difficult to get out. Do you get 100% clean bubble-less fluid out of the bleeders? Every time? I know someone before mentioned how hard it is to bleed the brakes on these cars without a pressure bleeder, maybe that is something to try. If not, I stand by my previous statement about the different hoses.

-JOE
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joesfiero
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Report this Post05-23-2008 11:18 PM Click Here to See the Profile for joesfieroClick Here to Email joesfieroSend a Private Message to joesfieroDirect Link to This Post
BTW I did want to add it is possible you got a bad MC. If it was a rebuilt one I would say you have a better chance of it being bad. Keep in mind a lot of "new" MCs from the discount stores are just rebuilt cores. If it is bad, however, you should have noticed it while bench bleeding it. I put one in a family member's 4 runner and went through no less than 4 bad MCs from Advance Auto Parts before getting a good one. When I tried to bench bleed it, it would never build any pressure. Good luck and let us know how it works out.

-JOE
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afRaceR
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Report this Post05-23-2008 11:22 PM Click Here to See the Profile for afRaceRClick Here to Email afRaceRSend a Private Message to afRaceRDirect Link to This Post
Like I said before, it is a royal pain to bleed the brakes correctly on the Fieros without a pressure bleeder. I've tried every other way. Jack the front up and bleed the back, then switch; one man bleeders; vacuum bleeders; stand on my head while I talk dirty to it, none of them work all that well on these cars except for pressure bleeding. You can eventually get the system bleed with conventional ways, it just takes awhile.

I have actually found that gravity bleeding works fairly well to get most of the air bleed, plus you don't have to do much work and you can drink alot of beer while yuo do it

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ray b
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Report this Post05-23-2008 11:27 PM Click Here to See the Profile for ray bClick Here to Email ray bSend a Private Message to ray bDirect Link to This Post
to bench bleed brakes
THERE IS NO NEED TO USE A BENCH

just bolt the MC in the car
use the plugs and clear lines that come in the box with the new MC
fill the MC rez and loop the clear temp line into the rez under the fliud
pump intill the bubbles stop
swap to the other plugs in turn
and pump intill the bubbles stop


NOTE IF YOU SKIP THIS YOU WILL NEVER GET THE AIR OUT
and will have a soft pedal
as the MC is the high point and the air will not bleed out thru the lines to and thru the calipers

then hook up the brake lines and let them fill with fluid
the hook the lines to the hose and or calipers
and bleed the calipers
be sure to get all the old fluid out along with all the air

BTW bleeding the system once a year is a VERY GOOD IDEA
as brake fluid collects water
and the water will damage the calipers inside and cause the lock ups
stick cars should also do the clutch line at the same time

------------------
Question wonder and be wierd
are you kind?

[This message has been edited by ray b (edited 05-23-2008).]

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antinull.com
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Report this Post05-23-2008 11:44 PM Click Here to See the Profile for antinull.comSend a Private Message to antinull.comDirect Link to This Post
Okay,
we are using sythetic dot 3 fluid
we bench bled the mc using plugs there were no tubes?
the mc built pressure fine bench bleeding it
we have run 3 large bottles of fluid through no old fluid or bubles
we bled the system 2 times
we adjusted the rears then installed newer replacement pads (they scrape while driving)
my EBRAKE works great now
but i still have low pedle
so, going to try driving it now

my former friend patrick says his wrist feels bettter after rubbing all the brake fluid on it bleeding the car for the last 6 hours
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Report this Post05-24-2008 12:20 AM Click Here to See the Profile for antinull.comSend a Private Message to antinull.comDirect Link to This Post
okay, the brakes are about 20% better and the ebrake grips sooner but still doesnt stop very fast
it seems as i drive more they get a little better then again the fronts are carbomets and the rears are stockish replacement pads
I still have no idea what the problem is
im going to my autocross school tomorow anyways
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skstibi
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Report this Post05-24-2008 02:39 AM Click Here to See the Profile for skstibiClick Here to Email skstibiSend a Private Message to skstibiDirect Link to This Post
I would think that if you bled the crap out of everything they would work pretty well. I took both calipers off the front of my GT (along with the entire suspension) and the brakes work fine after bleeding.

My other thought would be a small hole in a brake line somewhere. Check around and make sure nothing is wet. Had this problem in my sisters '71 Bug.
Another thing, Synthetic brake fluid makes things leak a lot more than regular. Same goes with motor oil.
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Report this Post05-24-2008 06:45 AM Click Here to See the Profile for antinull.comSend a Private Message to antinull.comDirect Link to This Post
::sigh:: we didnt realise we were even using synthetic untill chris hahn87 mentioned it.....
i might run regular through when i replace the remaning hoses/lines when i get more $$
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Report this Post05-25-2008 06:26 PM Click Here to See the Profile for antinull.comSend a Private Message to antinull.comDirect Link to This Post
well i lost my class to the corvette by about 1.5 seconds
i did alot better than last year and it was a hell of alot of fun driving the fiero with the new suspension
Thanks to everyone here who has helped me fix my suspension and brakes

my brakes still are not 100%
but i figure new lines/hoses and non synthetic fluid will fix that
but thats for another day

[This message has been edited by antinull.com (edited 05-25-2008).]

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Report this Post06-09-2008 10:14 AM Click Here to See the Profile for antinull.comSend a Private Message to antinull.comDirect Link to This Post
Well i have chewed through a brand new pad on the passenger rear lol
looks like new hoses all around will probably even my pressure
(that hose is SS)
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max1
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Report this Post06-09-2008 01:21 PM Click Here to See the Profile for max1Click Here to Email max1Send a Private Message to max1Direct Link to This Post
The only time I ever had a "soft" pedal that went almost all the way to the floor before working was when I didn't bleed My brakes right. I had changed the rear calipers and not thinking it through I only bled the rears, figured They were the only ones I broke the lines to. 1st time I had to apply the brakes I felt it at the pedal, the brakes worked, just not right. I was on My way to visit My Parents who lived nearby so I just kept going and planned to re-bleed when I got home. I had already realized I should have bled all 4 but when I got to talking to an Uncle of Mine that was there visiting too, He's a mechanic.....said I had uneven pressure going to My brakes so that was the cause, just re-bleed them but re-bleed them all. The uneven pressure is what ate up Your right rear pad I imagine.....I use speed bleeders so I can do it Myself and never had a problem bleeding brakes with them...other than when I didn't do it right..lol...Doh!
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