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Is my booster bad?

  • Thread starter Thread starter Les_Sr
  • Start date Start date Mar 11, 2004

Les_Sr

New Member
Feb 29, 2004
13
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0
Mar 11, 2004
#1
  • Mar 11, 2004
  • #1
I have a 90 LX 2.3, when I start the car in the morning and go to leave the first time I step on the brake it goes to the floor. every time after that it gets slightly tighter until the brakes drag. Usually about 5 times on the brake pedal and the brakes are draging. After it sits for a while it will go to the floor again (loosing vacuum?). Could this be a problem with the brake booster? Thanks for any input.

Les
 

mr_woodster

Active Member
Jul 28, 2003
1,314
0
36
Riverside, CA
Mar 11, 2004
#2
  • Mar 11, 2004
  • #2
you mean our cars came with something besides an E(entertainment!)- brake? hm, learn something new everyday!

have you check your resivor for brake fluid? it that is staying constant, maybe bleed your lines, perhaps have some air in them. If that (which is the cheapest fix) doesnt work first, then i would say on to the booster.
 

bhuff30

Founding Member
Dec 11, 2001
6,037
35
129
Olathe KS
Mar 11, 2004
#3
  • Mar 11, 2004
  • #3
sounds like it could be a master cylinder leaking.
After you drive a while, when you push on the brake, does the pedal slowly drop? if so, that is the MC.
 

Les_Sr

New Member
Feb 29, 2004
13
0
0
Mar 11, 2004
#4
  • Mar 11, 2004
  • #4
No, once the pedal gets tight it stays really hard, only moves a very little. The fluid is fine and the breaks have been bleed several times to try to fix the problem. The MC and the front calipers are newly rebuilt (from autozone) less that 2 months ago
 

mr_woodster

Active Member
Jul 28, 2003
1,314
0
36
Riverside, CA
Mar 11, 2004
#5
  • Mar 11, 2004
  • #5
well if you hold the pedal and it STAYS right where it is, then the MC should be fine, if allthose things are new and not leaking, that doesnt leave much but the booster? looks like you have your answer before you asked
 

khal101

Founding Member
Aug 25, 2002
358
0
0
Richmond, VA
Mar 11, 2004
#6
  • Mar 11, 2004
  • #6
To check your brake booster, turn off your car and pump the brakes until they are tight. If your pedal goes down some then you're booster is ok. If the pedal stays where it is then you're booster is bad. Also you may want to check your "check valve" on the booster. It is a one way valve. It is located under the hood on the booster itself. One part should have a hose on it, the other side is connected to the booster. Pull that off the car and blow in it. You should be able to blow one way through it and air goes through, but blow the other way and no air should pass through. If that doesn't happen, replace it and see if that helps.
 
P

Paul C.

Founding Member
Aug 27, 2001
321
0
0
Thrall,TX
Mar 11, 2004
#7
  • Mar 11, 2004
  • #7
You may need to replace the rubber lines. I've had this happen to a couple of cars. They look fine but swell up on the inside. If you open the bleeder the fluid will spurt out @ high pressure. This is because the fluid can't move freely thru the line.
 

Les_Sr

New Member
Feb 29, 2004
13
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0
Mar 11, 2004
#8
  • Mar 11, 2004
  • #8
Thanks for all the suggestions, I am going to replace the caliper hoses with braided steel lines and I ordered the booster from Advance today... We'll see what the cause is very soon I hope! I do believe it is the booster!
 
D

Dan'l

Founding Member
Aug 2, 2001
1,539
0
0
wisconsin
Mar 12, 2004
#9
  • Mar 12, 2004
  • #9
Back brakes are way out of adjustment, so they give no resistance untill the pedal has been pumped a few times. Jack the back up and adjust the rear brakes up(yes we do have rear brakes, marginal as they may be) until they start to drag when the wheels are rotated.
 

Les_Sr

New Member
Feb 29, 2004
13
0
0
Mar 12, 2004
#10
  • Mar 12, 2004
  • #10
the brakes already drag on all 4 corners without adjustment. I have sat the car on jackstands and pumped the brakes and none of the 4 wheels will turn after they're tight, I had to open the bleeder screw and release the presure from the calipers to be able to turn the wheels freely.
 

Les_Sr

New Member
Feb 29, 2004
13
0
0
Mar 13, 2004
#11
  • Mar 13, 2004
  • #11
Well, I replaced the booster and it solved the problem, The only thing now is the new booster would not adjust out any farther and there is a good bit of travle in the brake pedal before the brakes engage.....
 

Asha'man

Founding Member
Feb 5, 2002
1,909
0
0
Denver
Mar 14, 2004
#12
  • Mar 14, 2004
  • #12
You can screw and unscrew the brake booster rod so it's longer or shorter where it connects to the brake pedal, might wanna try that.

Ash
 
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