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Old 16th May 2008, 20:28   #76
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Quote:
Originally Posted by srishiva View Post
I want to emphasize what simplythebest said. check the brakes and take a break. Allow them to cool down.
This is what the authorities do abroad. While coming down from a mountain, they check the temperature of your brakes midway and will ask you to take a break for 30 minutes.
Pls , I dont think any break is required if one knows how to drive properly -- !! And if you don't know how to drive properly then I guess you shudn;t be anyways driving in such situations cause you could be a hazard to others .

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Originally Posted by srishiva View Post
Don't know why auto manufacturers do not give a temperature sensor for brakes and warn if overheated.
Why dont we have manufacturers give sensors for everything ... infact why don't they make cars that work on audio control -- control a car with ones voice :-) ?


As for downshifting and the effect on the clutch .. if done properly then it doesn change/damage it much . And don't ask on the right technique to down shift as its not a thing that can be explained in theory .

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Old 16th May 2008, 20:33   #77
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This was not a fade but a boil over of brake fluid due to excessive heat. Even a small vapor bubble due to boil over will make the pedal go to the floor (hydraulic theory). The moment things cooled you got the brakes back as the vapour lock either got breathed out or condensed.

Answer, apart from anything else, is to do a complete bleed and fluid change. Opt for higher rated fluid to be really safe. I would really be concerned why this occurred.

The pad wear will not feel as pedal going down but feels as if there is no braking even with pressure on the pedal.

I agree with many here who have said that the fade builds up and a wise driver realizes this and slows down or takes a break.

The black dust on wheels are anyways result of heavy breaking and you can see this even after a long highway run at high speeds where you have to break hard many times.
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Old 16th May 2008, 20:55   #78
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Quote:
Originally Posted by sudev View Post
This was not a fade but a boil over of brake fluid due to excessive heat.
Sudev, a 'boil over' of brake oil cannot happen in isolation from brake fade. The two ALWAYS go hand in hand.
And fade does not necessarily mean total 'wear down' or wearout of pads. The phenomenon is that the brake-drums expand much more than the piston/pad assembly. Simultaneously, fluid vapourizing may occur, which will lead to 'total' loss of pedal feel.

The described event is, in fact, a 'classic' example of severe brake fade.
Luckily, the vapourization saved the day in that it did not allow the 'nearly molten' pads to connect with the drums. Had that happened, it would have destroyed the pads completely.
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Old 16th May 2008, 22:02   #79
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Originally Posted by anupmathur View Post
Sudev, a 'boil over' of brake oil cannot happen in isolation from brake fade. The two ALWAYS go hand in hand.
Abs correct. What I mean is that this was more than a fade. And the OP should have recognized brakes getting hot much before this situation happened.

As to drums expanding...sorry the total expansion is not that much. Do some calculations and you will see what I mean. And the front is disc and not drums so even if expansion of that magnitude occurs it will make the pads travel even lesser.

Ever seen rally shots with discs glowing red hot? Even at that sort of temperatures the pas do not melt. Yes I know they use ceramic pads+carbon discs and all that but I have yet to see or hear about a fused pad and disc.

Anyways getting vapor lock is bad and OP needs to make sure that he changes the fluid.
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Old 17th May 2008, 02:58   #80
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I silly question from a newbie:-

Situation:
I am driving uphill(going up) on a very steep slop.
Now for some reason, engine get turn off & car starts going backwards instead of forward.

Here is what i do now. please point out mistakes

1) press handbrake immediately to stop backward motion
2) get to neutral & start the engine again.
3) press clutch & throw gear stick in 1st

what would be the next steps?
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Old 17th May 2008, 04:51   #81
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Quote:
Originally Posted by gary4gar View Post
I silly question from a newbie:-

Situation:
I am driving uphill(going up) on a very steep slop.
Now for some reason, engine get turn off & car starts going backwards instead of forward.

Here is what i do now. please point out mistakes

1) press handbrake immediately to stop backward motion
2) get to neutral & start the engine again.
3) press clutch & throw gear stick in 1st

what would be the next steps?
Pulling handbrake is fine but I still advocate the foot brake ... I drive in the hills a lot and sometimes engage the hand brake only during parking . What you need to practise is finding the sweet spot with your car's clutch . I refer to it as the sweet spot as its very important when driving in the hills and if you know that point you will not need the handbrake to start from a standstill even in the steepest of slopes .

Sweet spot is the point where the clutch on being released engages into the gear but there is no forward or backward motion even when on a steep incline/decline .... once you find that spot , all you need to do is press the throttle and release the clutch slowly and you will move forward . If you can learn this then trust me you won't need to use the handbrakes .

Cheers
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Old 17th May 2008, 06:28   #82
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@OP - If it is really steep slope first point of decision will depend on if you car has enough torque to take a standing start on it?
If yes. Stamp on brakes and clutch. Restarts the engine and pull out.
If no, use brakes and good sense to roll back to a spot from where you can move forwards (or back). Sometimes it may make sense to guide the car in to a situation where the bodyworkd presses against hill side / solid object and comes to a rest so that you can take a deep breath, pray and then think what next ;-)
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Old 17th May 2008, 10:40   #83
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Sudev is right. It depends on how steep the road is and your car torque. If slope is too great and car does not have enough torque to pull off from standstill. The only choice is to back down until you reach area where slope is less steeper and gather enough speed.
However if your car has enough torque but you are not smooth enough with the control pedals (brake, clutch, gas). It is best to find a rock and jam it under the wheel(s).
Car these days have good brakes. Early days, I had lots of experience getting stuck in steep slope in Ambassadors. Ambassadors will not stop in such situations especially when backing. So I am always prepared.
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Old 17th May 2008, 11:48   #84
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Downhill drifts anyone? Now you know where to invest your next 100,000 Rs. in. Bigger discs, wider tires and stiffer shocks.

On a serious note, most of the suggestions mentioned in the thread so far are adequate, although I'd like to add that while downshifting from a higher gear and using the engine brake, you might want to blip the throttle and do a little rev matching. It will also reduce the "jerk" you experience while downshifting and make the shifts a lot smoother and quicker. And that way you also save the synchros and hence the gearbox in the long run.

Remember brake pads are much cheaper to replace than your transmission.
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Old 17th May 2008, 12:29   #85
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Quote:
Originally Posted by kaynmantis View Post
Ambassadors will not stop in such situations especially when backing. So I am always prepared.
Anyone who has driven those bygone era vehicles on hill roads will have no trouble at all with the current crop of cars!

The handbrake in those old cars were largely a myth; they never held on any incline. Everyone was perfectly accustomed to using pedal techniques and gears to hold the car on a gradient!
Even brakes used to be far less effective and changing gears used to be an art form - each car had its own unique character!

This thread has hardly anything to 'teach' such veterans from the yesteryears.
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Old 17th May 2008, 12:38   #86
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To practise your skills with the pedals, try stopping the car, while climbing an incline without using the the brakes

Then move forward without even an inch of movement in the reverse direction.
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Old 17th May 2008, 13:32   #87
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Just came across this thread.
Very informative and is helping me correct my driving in hills.
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Old 17th May 2008, 13:35   #88
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Quote:
Originally Posted by bblost View Post
To practise your skills with the pedals, try stopping the car, while climbing an incline without using the the brakes

Then move forward without even an inch of movement in the reverse direction.
I used to do this earlier, but I read somewhere that it could be hard on the clucth plates, so I changed over to handbrake technique thereafter.
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Old 17th May 2008, 13:40   #89
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Hmm. quite an interesting thread this. I have little experience in driving on the hills. I have mostly driven up-hill and and very little down-hill runs. I was aware that the brakes will fade on heating due to continuous use, but never ever imagined that braking will completely 'disappear'

Quote:
Originally Posted by anupmathur View Post
On any stretch of the road, the Vehicle going uphill has right of way.
Religiously stick to your lane, particularly on hairpin bends & blind curves.
Sticking religiously to our lane is not a very good idea,IMO when you are in a hairpin and you have the outerlane. If a bus/truck comes to the hairpin at the same time, it will be impossible for it to do the hairpin in the inner-lane(and in all probabilities, he will be in your lane). lane-switching has to be done here so that the car gets into the inner lane giving outer-lane for the heavy vehicle. Of course both the drivers must 'understand' this else will be a disaster!!

In normal cases, as you said sticking to the lane is the best practice.
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Old 17th May 2008, 13:49   #90
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For hilly region here is my advice:
1. drive slow.
2. drive in low gear.
3. keep the radius minimum, horn and be very carefull of cars from other side on
turns.
4. keep as close as to the mountain side as possible.
5. If you have a co passenger ask him/her to keep an eye far on the road (as the
mountain road is zig zag and cars many a time can be seen from far off so you
know in a minute you would be crossing it).


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