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Having some braking problems. Anyone had a similar issue?

  • Thread starter Thread starter stang8urimport
  • Start date Start date Jul 19, 2007
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Fett

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#21
  • Jul 20, 2007
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You might also want to unbolt the master from the booster and look inside the back of the master. I have seen a lot of reman masters have a slight leak internally, causing the same issues.
 

Nibbie

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#22
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If the booster had a leak of anysort will it be dripping brake fluid in the engine bay or under the dash near the firewall? I dont know but thats what happend to me once. Oh if the calipers where bad the brake pads would wear unevenly, I see that somtimes with cars/trucks.
 

Fett

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#23
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If the booster had a leak, he would hear it. The booster doesn't contain fluid.

If a master is leaking bad, you will see the paint on the booster start to bubble and peel away just under where the master is mounted. But that is a normal leaking master. I have seen a lot of reman masters have a very slight leak, that hurts pressure when applying the brakes. You can notice this by unbolting the master from the booster and looking at the booster rod and inside the master. It should be dry of fluid.
 

jrichker

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#24
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If you have a low vacuum condition (less than 17" at idle), the brake booster may not supply all the assist you need with your particular combination of pads and rotors.

Check out the booster and vacuum lines for leaks. Do a basic vacuum test to make sure you have good vacuum (more than 17") at idle speeds.

Pay close attention to the rubber gromment that the brake booster check valve fits in. Also pull the check valve out and try blowing though it. One way it should pass air, the other way it should block all air with no leaks. If it leaks at all replace it.
 

stang8urimport

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#25
  • Jul 20, 2007
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I agree with a leaking master cylinder would do that.. But I've seen many seals rolled in a master with no visible leaks giving the same problems. Thus I replaced it. I think I will look more into it this weekend. Thanks a lot guys for all your help. I didn't mean to be an ass... I'm just getting frustrated.
 

Roland69

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#26
  • Jul 20, 2007
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have you inspected the rear wheel cyl's for any signs of leaks... (or are you 4 wheel disc)

My initial thoughts was booster ( I knew you would check the basics since you are a fellow tech)

did you feel any pedal fade at all


check the vac line to the booster maby you are loosing some vac there causing bad power assist
 

stang8urimport

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#27
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Wheel cylinders are good. They're new. Vac line seems to be in good condition. It might possibly be a booster problem.
 

Mustang5L5

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#28
  • Jul 21, 2007
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Might i suggest a 93 cobra booster as a replacement, especially if you are considering any future brake upgrades
 
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BullittAndy

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#29
  • Jul 21, 2007
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If its not the booster then you might replace the front pads with another softer set. I had a set of performance pads that after the install had the exact same problem, hard brake pedal but no brakes.
 

Roland69

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#30
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can you just go to a parts store and buy a BB for a 93 cobra
 

stang8urimport

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#31
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Roland69 said:
can you just go to a parts store and buy a BB for a 93 cobra
Click to expand...

Yep, but it will probably be special order
 

Mustang5L5

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#32
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Yes. but it's special order

http://www.autozone.com/R,APP272231...partType,00143/shopping/partProductDetail.htm
 

Roland69

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#33
  • Jul 21, 2007
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what about a SN95 booster and master will the work fine on a fox without much mod's
 

Fett

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#34
  • Jul 21, 2007
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Yea, but everything I read says that a 93 Cobra BB is a direct swap, and the master only requires modification to the lines and PV because of the missing port.
 
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