Michaels-Volvo-Offroader-Forum | SPEZIELLE THEMEN | Bremsspur / brakes | « vorheriges Thema folgendes Thema » |
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Autor | Thema: Problems with brake (Gelesen 3119 mal) | |||
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Hi all,
I have a problem with my brakes. It's strange, when i press my brake pedal suddenly my right front wheel brakes very very hard (it's stops imidiately and blocks for a second). Problem is also i got no feeling over my pedal, it's all or nothing, so braking slowly is out of quetion. Sometimes it goes over after several dangerous braking manoevers but today even not after 10 tries. Can somebody help me? Hallo alle, ich habe ein Problem mit meinen Bremsen. Es ist seltsam, wenn ich meine Bremse plötzlich mein rechtes Pedal Vorderradbremsen sehr, sehr hart (es hält imidiately und Bausteine für eine Sekunde) drücken. Das Problem ist auch ich habe kein Gefühl über mein Pedal, ist es alles oder nichts, so Bremsung langsam aus quetion. Manchmal geht es über nach mehreren gefährlichen Brems-Manöver aber heute auch nicht nach 10 versucht. Kann mir jemand helfen? | ||||
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I receive no warning lights!
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Hmm....can't answer the complete/agressive blocking itself, perhaps someone else has a suggestion? However: do all wheels brake equally, left/right and front/rear? (try disconnecting (shorting!) the brake-pressure sensor on the right side of the steering collumn, to avoid 4wd engaging (and messing up this part of the analysis)) But if the problem in your case is also that the brakes *stay* locked, then you might have a problem with quilled/swollen flexible brake lines....with age, they can swell up inside, blocking the hydraulic flow, but only in one direction (open up at pressure, close when pressure drops), mysteriously working as a one-way valve. Any other explanation for agressive locking should be found in the wheels itself I believe, as if the brake shoe's are too much 'self-inforcing'....but I have no clue how they could, physically. (even removal of all return-springs shouldn't cause this behaviour) Maybe Jochen can come up with some other possible scenario's, he has analysed the entire brake system from front to back, and even seems to have found the solution for another Volvo-typical persisting problem, trapped air (only full brake power after second pedal push). PS: can you exclude ice build up or baked mud, in the wheels, as possible alternative causes? | ||||
*Verkaufe Battery-Equalizer/Charge-Balancer/Wandler 24->12v/100A* Those who wander are not necessarily lost J.R.R. Tolkien ...and not all who launder are washed/WJ....;)) <w.j.markerink@A1.NL>
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The brakes don't stay locked. The flexibel of the right front have been changed 6 months agoI checked all the brakes and wheels, i cleaned it all.
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hello,
when you only change the right brakehoses maybe the other brakehoses are closed now and all force works on this wheel? ingo | ||||
schraubst du noch, oder fährts du schon?
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I have had a problem which looks alike: one front wheel is sometimes blocking while braking, even very soft braking. The reason was an old and rusty wheel cylinder. I believe it is a reason behind it in the construction of the drum brakes - every drum brake: On the front more than on the back the brake shoes are adjusted to produce an effect like power braking, because the drum will rubb on the shoes and the line of power is outside the turning point of the brake shoe. That will push the brake shoe to the outside and the pressure on the brake will be more - like power braking. Normally the springs in the wheel will bring the shoes back in the moment you lower the pressure on the pedal - the foot is very sensible to adjust the right pressure. It is a pulsating circuit - more - less - more - less. If the wheel cylinder is blocking the way back then it will only move outward what will bring the wheel to blocking as well. In most cases there are two ways to let the blocking end: A short very hard pushing the brake may help, by putting more power on the springs to pull the brake shoe back, but it is unlikely. The other way is by chance: If you lower the pressure one brake shoe brakes more, one brakes less, and the wheel cylinder is not following. There opens a gap between the wheel cylinder and the end of the brake shoe. Because the force is only on one half of the drum it will not be straight as it should be, and if the drum and the shoe come out of line there will start a kind of vibration and the shoe will jump back drawn by the springs. It hits the wheel cylinder from 1 or 2 mm above like a hammer and push it against the rust back to normal position. For me it was a first help to adjust the brake shoes in a way that the wheel cylinders worked in an other base position - even 0.5 mm are a big difference to avoid the rusty step on the inner side. I changed the wheel cylinder and the problem was gone. good luck michael | ||||
"oh, for sure, you can do it with a normal streetcar...."
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Sorry, I indeed overlooked that you wrote 'right front wheel'....;)) And since you went into the wheel drum itself, another possible scenario can probably also be ruled out, that of a brake lining separating from the shoe (not impossible with old/original components!), and somehow jamming/wedging itself in there....though I am not sure what the typical & possible failure-mode scenario's could be in that context....Jochen? Does the left front wheel brake at all? Same condition of slave cylinders & shoes/lining/drum? Btw, if your problem doesn't appear to be destructive or even just fast-wearing-down-components, we surely would like to know what might be needed to upgrade the brakes to get so much more(?) braking power....;)) | ||||
*Verkaufe Battery-Equalizer/Charge-Balancer/Wandler 24->12v/100A* Those who wander are not necessarily lost J.R.R. Tolkien ...and not all who launder are washed/WJ....;)) <w.j.markerink@A1.NL>
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Hej ChristophS!
Remove at first the Breakdrum and check if the return-springs are all mounted and in good contitions. Check all the moveable parts if they work well. Maybe, the old breaklining are very hard, replace it. New ones will be softer, the break works more sensitive. Good luck. Timo | ||||
keep your motor clean!
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Michaels-Volvo-Offroader-Forum | SPEZIELLE THEMEN | Bremsspur / brakes | « vorheriges Thema folgendes Thema » |