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Old 15th February 2009, 21:36   #46
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On the steep gradients and bad roads the oil from the filled up half of the reservoir kept getting splashed into the empty portion and getting lost.
That makes sense, it is quite possible especially when driving on steep slopes or bumpy roads. On highways it should be hopefully less serious. Based on this thread, I have drawn following conclusions that everyone should be aware of-
1. Do not take dual-circuit theory for granted, there is some chance, though a slim one, that even a single leak may lead to total failure.
2. You must have handbrake in properly working condition, which is much lesser effective, but it may rescue you in case of brake failure.
3. You must ensure that there is a lot of clearance from brake pedal to floor, it may give you more time to fix the problem after a leak develops (provided it is detected).
4. While all dashboard warning lights are to be taken seriously, the brake warning is particularly important. I wish all warnings were accompanied by an audible buzzer as well. While driving, it is possible that you may not notice a red light, but a sound can not go unnoticed.

OR
Forget everything and just make sure you carry boot full of bananas all the time! Stuff them whenever and wherever required

BTW, coincidentally, I read that 2CV story on it's 50th anniversary!
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Old 15th February 2009, 21:47   #47
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Forget everything and just make sure you carry boot full of bananas all the time! Stuff them whenever and wherever required
BTW, coincidentally, I read that 2CV story on it's 50th anniversary!
That's about when I'd read it too!
But I am inclined to imagine, that like SS before you, you are taking the bananas too seriously and professing them as a cure-all!!
Application of mind .... remember?!
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Old 16th February 2009, 10:59   #48
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Brake fluids are hygroscopic. If a can/bottle of fluid has been left standing for long without being tightly capped, the fluid will have absorbed moisture.
This can cause emulsification and will certainly cause lowering of the boiling point of the brake fluid.
The hygroscopic nature of the fluid is main reason why periodic replacement is necessary. It hard braking it is possible for the (absorbed) water to come out as steam which is like air in the brakes.

I did have a friend who drove his car around for four years, had a wheel cylinde rjam, an we found the oil had become a gel inside it.
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Old 16th February 2009, 11:13   #49
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Originally Posted by sgiitk View Post
It hard braking it is possible for the (absorbed) water to come out as steam which is like air in the brakes.

I did have a friend who drove his car around for four years, had a wheel cylinde rjam, an we found the oil had become a gel inside it.
I've also seen such gelling of the brake oil due to water sorption, but don't remember such a thing happening after DOT3 fluids were introduced (around the same time as Marutis came to India). Vapour formation in the wheel cylinders under repeated hard braking can lead to "brake fade" - can happen even if the brake oil itself starts to boil. That's the main reason why downhill drives are to be done in gear using engine-braking, rather than depending on the brakes completely all the time.
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Old 16th February 2009, 15:34   #50
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Vapour formation in the wheel cylinders under repeated hard braking can lead to "brake fade" - can happen even if the brake oil itself starts to boil.
Can you please elaborate- What is it and how does it happen?
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Old 16th February 2009, 21:58   #51
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Can you please elaborate- What is it and how does it happen?
Heavy braking causes heat generation (can even be 500 deg C), which in turn does two things - heats up the brake oil, and cooks the brake shoes/disc pads. Poor quality brake oils or old oils which contain hygroscopically absorbed water, will boil at these super-high temperatures and form vapours inside the wheel cylinder - since vapours/gases are compressible, the hydraulic effect of transferring your foot pressure from the master cyl to the wheel cyl does not happen. As a result, even when you stand up on the brake pedal, a faded brake refuses to stop the car. Also poor quality shoes/pads can "melt" and lose their frictional properties, leading to fade.

Brake discs, ventilated discs, drilled discs etc. were inventions only to prevent brake fade by exposing more surface area to the airstream - otherwise, drum brakes are equally good at stopping your car.

Check the information at Brake fade - Wikipedia, the free encyclopedia.
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Old 11th March 2009, 19:44   #52
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Since I have been physically checking brake fluid every day, I thought of waiting for some more time and watch. It has been over 5 weeks now, and there is not even a single mm of drop! So, I conclude that there is no need to do anything for now. If still there is any possibility of onset of a leakage in that cylinder, then I think that should be equally probable for rest 3 cylinders as well! Will consider brake overhauling 2 years later (when next fluid replacement will be due).

I have stopped making manual checks now, but I do check dashboard lights before every start (well, almost), as per my good habit, and manual check before long trips.

Thanks for all the responses!!
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Old 11th March 2009, 21:55   #53
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I have stopped making manual checks now, but I do check dashboard lights before every start (well, almost), as per my good habit, and manual check before long trips.
And what are your views about keeping some bananas in the car, for contingencies, LOL!!?

Seriously, your car's brake system seems to be in satisfactory condition presently. All the best!
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Old 11th March 2009, 23:16   #54
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Right now I am busy getting a subwoofer to be kept in the boot, no space for bananas!
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