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braking issue

  • Thread starter Thread starter skywalker
  • Start date Start date Aug 20, 2004
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skywalker

Member
Dec 22, 2003
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Pensacola, FL
Aug 20, 2004
#1
  • Aug 20, 2004
  • #1
Okay, I've had this problem since day one with my brakes.
When I go to stop I have to "pump" the brakes to get good strong pedal feel when braking.

I originally had drums and the problem continued after my disk brake conversion. I've replaced most of my brake lines, have no apparent leaks and a new master cylinder. I've bled the living piss (figuratively) out of the brakes. I did a bench bleed on the master cylinder when I installed it.

what the heck is going on?
 
D

dj747

New Member
Mar 25, 2004
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Aug 20, 2004
#2
  • Aug 20, 2004
  • #2
I had a similar problem and it turned out to be the power brake booster. I can't figure out why pumping had an effect, but it fixed mine. Time for a new vacuum booster?
Good luck
Dan
 

skywalker

Member
Dec 22, 2003
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Pensacola, FL
Aug 20, 2004
#3
  • Aug 20, 2004
  • #3
manual brakes. So booster is ruled out.
 
O

Ozsum2

New Member
Jul 28, 2004
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Aug 20, 2004
#4
  • Aug 20, 2004
  • #4
new lines, new MC, gotta still be air in the lines or it is getting in there from an un-sealed breeder screw.
 

skywalker

Member
Dec 22, 2003
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Aug 20, 2004
#5
  • Aug 20, 2004
  • #5
I'll double check that (in fact I think I'm goint to get some speed bleeders) but I swear, I've done everything I could to prevent that. I actually snapped a bleeder screw in half tightening them down.
 

Cdaniel

Founding Member
Nov 29, 2001
220
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Arizona
Aug 20, 2004
#6
  • Aug 20, 2004
  • #6
Do you still have rear drums? Could be out of adjustment, worn linings or drums turned out to much. Or a combo thereof.
 

Cdaniel

Founding Member
Nov 29, 2001
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Arizona
Aug 20, 2004
#7
  • Aug 20, 2004
  • #7
Cdaniel said:
Do you still have rear drums? Could be out of adjustment, worn linings or drums turned out to much. Or a combo thereof.
Click to expand...

Nevermind, I just noticed the 4 wheel discs in your sig line.
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
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98
Cape Cod, Ma.
Aug 20, 2004
#8
  • Aug 20, 2004
  • #8
Cdaniel said:
Nevermind, I just noticed the 4 wheel discs in your sig line.
Click to expand...
IF it's 4 wheel disc , does it have a master capable of filling the rear calipers or is it a drum rear master? Calipers take more fluid than wheel cylinders
 
O

Ozsum2

New Member
Jul 28, 2004
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Aug 20, 2004
#9
  • Aug 20, 2004
  • #9
Ozsum2 said:
new lines, new MC, gotta still be air in the lines or it is getting in there from an un-sealed breeder screw.
Click to expand...




"breeder screws?" I really need to start proof reading.
 

skywalker

Member
Dec 22, 2003
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Aug 20, 2004
#10
  • Aug 20, 2004
  • #10
Ozsum2 said:
"breeder screws?" I really need to start proof reading.
Click to expand...


Don't worry, I do it too. It is a sign of superior intelligence.

I'm not sure if my master cylinder is big enough indeed (anyone want to suggest a good one for 4 wheel discs?) but I had this same problem with 3 wheel drums.

I was looking at a couple of wilwood aluminum ones but none seem that they will easily bolt up.
 
O

Ozsum2

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Jul 28, 2004
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Aug 20, 2004
#11
  • Aug 20, 2004
  • #11
skywalker said:
Don't worry, I do it too. It is a sign of superior intelligence.

I'm not sure if my master cylinder is big enough indeed (anyone want to suggest a good one for 4 wheel discs?) but I had this same problem with 3 wheel drums.

I was looking at a couple of wilwood aluminum ones but none seem that they will easily bolt up.
Click to expand...


Yea, since you had it B4, I'm thinking it isn't a parts compatibility problem, but a mechanical gremlin thing.
 

skywalker

Member
Dec 22, 2003
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Pensacola, FL
Aug 20, 2004
#12
  • Aug 20, 2004
  • #12
Ozsum2 said:
Yea, since you had it B4, I'm thinking it isn't a parts compatibility problem, but a mechanical gremlin thing.
Click to expand...

Yes and it's pretty bad too, sometimes the car will barely get brake pressure upon initially pressing the brakes. Not something I'm happy with.
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Aug 20, 2004
#13
  • Aug 20, 2004
  • #13
Ozsum2 said:
Yea, since you had it B4, I'm thinking it isn't a parts compatibility problem, but a mechanical gremlin thing.
Click to expand...

IF you had it before it could have just been the brakes out of adjustment

if you have to pump more than once to get the piston to reach the caliper, either the piston is too far away from the caliper or the master is not putting out enough fluid to push it far enough.

If you have air in the system, you'll always have a spongy pedal regardless of how many times you pump it, because air compresses.
 

monk302

Founding Member
Apr 18, 2001
742
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16
New Jersey
Aug 20, 2004
#14
  • Aug 20, 2004
  • #14
I was having a similar problem with mine and what had happened was I put the calipers on the wrong side. I switched them and it was fine. I still cannot believe I put them on the wrong side. Oh well, I can put someone through the windshield now.
 
O

Ozsum2

New Member
Jul 28, 2004
695
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Aug 20, 2004
#15
  • Aug 20, 2004
  • #15
WORTH said:
IF you had it before it could have just been the brakes out of adjustment

if you have to pump more than once to get the piston to reach the caliper, either the piston is too far away from the caliper or the master is not putting out enough fluid to push it far enough.

If you have air in the system, you'll always have a spongy pedal regardless of how many times you pump it, because air compresses.
Click to expand...


Then you'd have air brakes.
 

68GEETEE

5 Year Member
Nov 21, 2003
481
5
38
Texas, USA
Aug 20, 2004
#16
  • Aug 20, 2004
  • #16
What MONK said is what happened to me too. Someone had installed the right caliper on the left wheel, and vice-versa, so the bleeders were positioned at 4 oclock instead of 12 oclock. . You can bleed them all day long, lots of fluid comes out, but the air is trapped in a pocket ABOVE the bleeder screw. . NO pedal. . I reinstalled them correctly, bled them and I have great brakes.

Note, the bleeder has to be at 12oclock position, when it is corrrect, the screw itself will most likely point to the rear of the car.
 

skywalker

Member
Dec 22, 2003
733
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Pensacola, FL
Aug 20, 2004
#17
  • Aug 20, 2004
  • #17
Only one problem with that: I have wilwoods in front which can go on either side and my rears are from a newer ford and they're on correctly. The pedal is spongy at all times...but to feel any pressure at all in the pedal, I have to pump it up. Oh well, maybe I'll try doing a vacuum pump bleed tomorrow.

No one has yet to suggest a good master cylnder for 4 wheel discs.
 

Cdaniel

Founding Member
Nov 29, 2001
220
0
16
Arizona
Aug 21, 2004
#18
  • Aug 21, 2004
  • #18
skywalker said:
Only one problem with that: I have wilwoods in front which can go on either side and my rears are from a newer ford and they're on correctly. The pedal is spongy at all times...but to feel any pressure at all in the pedal, I have to pump it up. Oh well, maybe I'll try doing a vacuum pump bleed tomorrow.

No one has yet to suggest a good master cylnder for 4 wheel discs.
Click to expand...


Maybe your master cylinder needs those residual pressure check valves?
 

67coupestang

Founding Member
May 31, 2002
509
2
19
Aug 21, 2004
#19
  • Aug 21, 2004
  • #19
skywalker said:
Don't worry, I do it too. It is a sign of superior intelligence.

I'm not sure if my master cylinder is big enough indeed (anyone want to suggest a good one for 4 wheel discs?) but I had this same problem with 3 wheel drums.

I was looking at a couple of wilwood aluminum ones but none seem that they will easily bolt up.
Click to expand...

I recomend one from a 98ish explorer. Its aluminum bodied, with the plastic res, I think its a 1 1/8" bore and the ports are on the outside, not facing the engine.. It will have a weird switch but just leave it unhooked. best of all about $25 in a yard.
 

skywalker

Member
Dec 22, 2003
733
0
16
Pensacola, FL
Aug 21, 2004
#20
  • Aug 21, 2004
  • #20
finding a junkyard with an explorer might be an issue for me. So I might have to buy new, with this in mind does anyone have any suggestions? Aftermarket even?
 
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