contaminated
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| posted on 6/8/08 at 09:00 PM |
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Brake help please
Just got back from a run and had a bit of a brake problem. I was taking it very easy luckily and coming down a hill when the car in front braked and
indicated to turn off. I applied the brakes and not a lot happened. It slowed down, but was in no hurry to stop. I would say there was perhaps a bit
more pedal travel and then what felt like very bad brake fade as I gradually slowed.
The above problem has remained - it doesn't matter how hard you brake, it just slows to a gradual stop rather than actually stopping. Forget for
instance doing an emergency stop! I figure there are three possible problems:
1. Air in system - but no obvious leaks or fluid loss. Resevoir full and why would you suddenly get air in there unless there was a leak?
2. Mechanical failure - bad disks or pads, sometihng come adrift. Not check properly yet but I doubt it.
3. Servo failure (I have one) - if you have a servo, if you start the car with your foot already on the brake you should feel the pedal soften as the
vacuum builds. Mine doesn't do this - the pedal stays hard. When you switch off and pump a few times there is no hiss and the pedal does n ot
stiffen. The one way valve back to the manifold is fine. There is some damage to the bottom of the servo, although it has not been punctured.
I guess I'll start by bleeding just in case - but I doubt that's the issue. Any comments appreciated and if anyone has an unused Ford
servo PM me for beer tokens!
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mookaloid
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| posted on 6/8/08 at 09:45 PM |
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Sounds like you have already sussed it - the servo - has the vacuum pipe come off?
Cheers
Mark
"That thing you're thinking - it wont be that."
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contaminated
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| posted on 6/8/08 at 09:54 PM |
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Sadly not, no.
The thing I'm confused about is what happens when a servo goes bad! Is the effect just non-servo assisted brakes, or does it bu**er them up
altogether?
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daviep
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| posted on 6/8/08 at 10:01 PM |
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You just end up with non-servoed brakes, but they'll feel like they're not working at all.
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Macbeast
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| posted on 6/8/08 at 10:29 PM |
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I still have the servo out of my Sierra and it could be in Maidstone on Sunday if that's any help ?
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contaminated
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| posted on 6/8/08 at 10:50 PM |
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quote:
Originally posted by Macbeast
I still have the servo out of my Sierra and it could be in Maidstone on Sunday if that's any help ?
It would be a big help - except that I'll be in Norfolk! Are you in Maidstone then? Plenty of places you could drop it if so.
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zetec7
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| posted on 6/8/08 at 10:59 PM |
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If I recall correctly, the way to test the servo is to put your foot HARD on the brake with the engine OFF, then start the car. If the servo is
working correctly, your foot will go fairly quickly to the floor. If this doesn't happen, the servo is definitely...uh...pooched.
Very uncommon failure these days (obviously for safety reasons, these things are generally pretty much bulletproof), - more common is loss of vacuum
supply to the servo canister, via cracked/poorly fitting hose, leaky fitting at manifold or servo, etc.
http://www.freewebs.com/zetec7/
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contaminated
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| posted on 6/8/08 at 11:11 PM |
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thanks - I'll check the connections again tomorrow
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Macbeast
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| posted on 6/8/08 at 11:27 PM |
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Contaminated - U2U awaits
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contaminated
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| posted on 6/8/08 at 11:47 PM |
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superstar!
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