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Hi again. A question on brakes please. I acquired my third AX !!!(soon my front drive will turn into a Citroen memorabilia fair with bits of AX hanging everywhere). I got the said the car for 50 quid and its almost perfect. Done 70k, and the owner had to get rid of it as he bought a new car and the tax on this one had finished and he didn?t have a drive. Anyhow, the car has a brake problem which I am hoping your wisdom will help me to solve in the shortest time. (by the way those who helped with me with my other AX?s gearbox, thanks, done what was said and its better now). On this one, I have to apply the brakes considerable harder than my other two AX to stop the car. First thought was worn pads, checked them, almost new. Checked the fluid, no leaks. Checked the cables, nothing slack. I was puzzled until I realised two things. First if I `pumped? rather than just press as hard as I could, then the brakes worked better, second it seemed only the front left wheel and the rear right wheel are providing much of the stopping power (when I braked hard on a wet road, these two wheel locked up). I then jacked up the back and realised that rear left wheel fail to stop at ALL when either the brake pedal is pressed or the handbrake fully pulled. I mean even with the hand brake fully pulled and someone pressing the brake pedal I can turn the wheel by my hand. So my question is, what are the likely chances of a single problem being related to both these issues? What could that be? And could that also be responsible for the over all lack of any braking force? Could just a worn shoe lining be responsible for all this? Or has a circuit failure happened somewhere? Or I can?t tell until I open the rear brake drum (which I will do the coming weekend)?
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Initial thoughts are that a master cylinder seal has gone, which would explain the "pumping up" technique working, and also why only one circuit is functional. (They are generally split diagonally, ie O/S/F and N/S/R wheels on one circuit, N/S/F and O/S/R on the other)
However, with the handbrake not braking the N/S/R wheel I'd be inclined to think that either there is a fault in the handbrake mechanism as well as a hydraulic leak, or else there has been some sort of catastrophic failure of the N/S/R wheel brake mechanism which has taken out the brake shoe (or at least the part that the handbrake cable connects to) and also damaged the hydraulic system causing total pressure loss in one circuit.
It's not clear from your post, does the handbrake function normally on the other rear wheel, or not work at all?
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DTD, the handbrake functions perfectly on the other rear wheel. in fact if anything it seems to be \"harder\" than normal on the other wheel. If i pull up the handbrake hard enough, whilst moving, the rear wheel will skid, which is something neither of my other AXs can do. I would be tempted to think your second thought is more in line with whats wrong, i.e. something majorly gone wrong in the wheel which has efected both the handbrake operation and the circuit on that wheel, but what??? i have not openned the drum yet, but i did take off the wheel just to have a look and the drum did look knackered. it was so rusty that i could `peel\' off sections of the outer ring with my hand, but it didn\'t look cracked.
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The brake cylinder inside the drum has probably failed and leaked fluid over the shoes rendering them U/S on both foot and hand-brake operations.This could also explain why the pedal feels better when pumped,as air can enter the system from this fault too.
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Sounds to me as if a rear brake mechanism has seized up and can't do anything. Not unusual for an old car - just had a similar fix done on 93K 205. Perhaps the owner used a carwash more than necessary, accelerating rust in normally dry places.
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The chances are both problems are down to one fault. You won't know until you get the drum off, but I'll bet as soon as you see it it will all make sense. I just fixed the brakes on a Volvo that had a soft pedal and was pulling to one side - just turned out to be a seized caliper guide pin causing both problems.
My money would be on something having come adrift in there meaning that the shoes are not making contact at all and the piston has emerged from the end of the slave cylinder, causing that side of the brake circuit to fail.
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Well the drum came off, and as always it was a surprise, in fact the surprise was nothing, there was nothing wrong in there!!! Actually what I thought was one problem which caused all those symptoms, turned out to be several problems which incidentally looked like they were related. As far as the handbrake went, the cable had rusted inside the outer casing and had snapped right before it went into the drum, so in fact although when I was pulling the lever I felt some resistance, it wasn?t pulling the shoes, it was the force of the outer case ballooning up. As for the Brakes, the problem was as far as I can see due to severe neglect of the car. I am not sure, but this is what I think happened. At some point in the past, the master cylinder had gone and one of the circuits had failed. I could check this because little oil was reaching the cylinder. I thought it might be just the piping, but I checked at the master and it wasn?t much coming out of there either. The vacuum assist was working and seal was fine as no hissing could be heard. Anyhow, the owner had obviously carried on using the car with this fault and somehow the back cylinder seized up due to rust (because the circuit had failed and they weren?t moving), then the neglect continued and rust developed on the pipes just after the flexible bit (when the pipe comes from the front, there is a section of flexible tubing so that the pipe can sit on the rear axle before it goes into the drum). Somehow from this, air was being sucked into the system but oil was no leaking out. Because the car is not loosing oil, but every time you de-air the system, it comes back. I don?t think it?s the master, because air is trapped only before one of the rear cylinders (the wheel that was not braking). Anyhow, what I thought would be a simple fix, has turned out to be major repair due to some persons neglect of the car. It is amazing how many people think a car is just a `machine? and don?t realise it almost has a life if its own and if you don?t take care of it, it will die. In this case a simple neglect of a faulty cylinder which cost 10 quid, damaged the entire system. Anyhow now I am faced with a complete new brake system, including a master cylinder, real cylinders, and new piping, plus the handbrake cable. So there you go. pink fluffy dice happens, but that?s life!!!
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