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Old 18th March 2016, 20:55   #241
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Since the quote about anticipation came, just a few minutes back saw an Innova and Linea crossing the highway junction in the place where I work at high speeds. Little did the two guys know (I suppose) that the particular point is the hot favourite among rural jaywalkers. Almost weekly, 2 RTA cases come to mortuary being hit by speeding vehicle. Though I am not supporting the jaywalkers, being a Medical College & Hospital junction, the car drivers should exercise utmost caution and anticipation while crossing that spot. I wonder how the villagers there survive after 40 years because every alternate human being I see there doesn't even have the basic idea to LOOK and cross a 4 laned NH. They walk, run, drive bikes at their own will. Having discussed with some of them as patients, they seem to have the mindset that, " It's our turf. Our village. The Govt has built roads in our place. The car guys should slow down and go. We can't stop for them ". (These were original words from their mouth). With a multitude of people with the above mindset running to and fro, please exercise caution while crossing that place. Always prepare for the worst and hope for the best.

Location :
Mundiyampakkam Hospital bus stop at NH 45. Just 5 kms from Vikravandi toll gate towards Trichy.

This information is shared to benefit the regulars in that stretch, both BHPians and public.
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Old 22nd March 2016, 22:25   #242
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re: Safe Driving on Indian Highways & Ghats

A few more points to make your night drives safe:

Close one eye when exposed to bright light to help avoid the blinding effect.

Move the eyes more slowly than in daylight.

Blink the eyes if they become blurred. Some people use clearine eye drops. Maybe it helps.

Concentrate on seeing objects. This helps while driving over river bridges. North India has a few long bridges. At times, the ripples in the water may make you dizzy.

Force the eyes to view off center. It avoids getting hypnotized by road markings.

Visual autokinesis can occur when you stare at a single light source for several seconds on a dark night.

The result is that the light will appear to be moving. The autokinesis effect will not occur if the driver expands the visual field.

It is a good procedure not to become fixed on one source of light.

Distractions and problems can result from a flickering light in the car. A phone, camera, GPS devices or chargers may have a blinking light.

We should try to eliminate any light source causing blinking or flickering problems inside the car.
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Old 1st June 2016, 10:28   #243
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re: Safe Driving on Indian Highways & Ghats

Amazing thread. More people should have access to this as our RTO's are not really doing a good job at conducting the necessary written and driving tests. The RTO's should also customize their tests as per the geographical locations.

e.g Driving on Ghats is altogether a different art than riding on expressways.
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Old 5th June 2016, 10:24   #244
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Brake fluid overheating in hill driving

Guys,

I am a frequent hill climber and while descending down, the thumb rule says to descend in 3rd gear or so, depending upon the steepness. I believe that this would act as engine braking rather than using the car brakes completely.

Recently, In my Ford Fiesta, While I was coming down from Ooty, I felt that the brakes went ineffective because the brake fluid got over heated and its properties became different. I had to pull my vehicle over and parked it for an hour till the brake fluid gets normal

Here are my doubts

1) I would like to know if there could be any additives that can be added to the brake fluid that may help over come this problem
2) When my brake fluid got heated, The brake pedal was dead and the brakes were completely ineffective. Why the manufacturer doesn't consider an option to override the hydraulic brakes with some kind of manual push-pull linkage under emergency situations ?
3) I know that there are even bigger hills in North India than Ooty. While descending down those hills, do people normally experience this problem?

Thanks in advance for your help

Last edited by Gannu_1 : 5th June 2016 at 10:30. Reason: Smileys = 2 per post. Please stick to the rules of the board. Thanks!
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Old 5th June 2016, 11:09   #245
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So I don't think it's the brake fluid but the brake pads which over heated and lost their grip due to over usage. Are you riding the brake while doing down? You might want to shift to an even lower gear to limit the usage of brakes
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Old 5th June 2016, 11:13   #246
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Re: Brake fluid overheating in hill driving

Quote:
Originally Posted by sriramaero View Post
Guys,

I am a frequent hill climber and while descending down, the thumb rule says to descend in 3rd gear or so, depending upon the steepness. I believe that this would act as engine braking rather than using the car brakes completely.

Recently, In my Ford Fiesta, While I was coming down from Ooty, I felt that the brakes went ineffective because the brake fluid got over heated and its properties became different. I had to pull my vehicle over and parked it for an hour till the brake fluid gets normal

Here are my doubts

1) I would like to know if there could be any additives that can be added to the brake fluid that may help over come this problem
2) When my brake fluid got heated, The brake pedal was dead and the brakes were completely ineffective. Why the manufacturer doesn't consider an option to override the hydraulic brakes with some kind of manual push-pull linkage under emergency situations ?
3) I know that there are even bigger hills in North India than Ooty. While descending down those hills, do people normally experience this problem?

Thanks in advance for your help
Do you keep the brakes continuously pressed or you press them say for a second or two and let them go when you have to slow down on a downslope?

The second option gives the brakes heat dissipation time, and what you are facing is the brake pads overheating, not the brake fluid.

I feel, its the technique of braking that you are using which is the problem (No offence), try a lower gear next time and the heat dissipation technique I told you above, see what happens. That is what I use all the time.
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Old 5th June 2016, 11:21   #247
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Re: Brake fluid overheating in hill driving

Quote:
Originally Posted by sriramaero View Post
Guys,

I am a frequent hill climber and while descending down, the thumb rule says to descend in 3rd gear or so, depending upon the steepness. I believe that this would act as engine braking rather than using the car brakes completely.

Recently, In my Ford Fiesta, While I was coming down from Ooty, I felt that the brakes went ineffective because the brake fluid got over heated and its properties became different. I had to pull my vehicle over and parked it for an hour till the brake fluid gets normal

Here are my doubts

1) I would like to know if there could be any additives that can be added to the brake fluid that may help over come this problem
2) When my brake fluid got heated, The brake pedal was dead and the brakes were completely ineffective. Why the manufacturer doesn't consider an option to override the hydraulic brakes with some kind of manual push-pull linkage under emergency situations ?
3) I know that there are even bigger hills in North India than Ooty. While descending down those hills, do people normally experience this problem?

Thanks in advance for your help
Buddy I have driven downhill on a variety of hills of varying steepness but have never faced this issue. Could it be that you used third gear when instead you should have used second and as a result were riding the brakes? How do you know for sure that the problem occured only due to overheating brake fluid? Did you get the brake pads and the rest of the system checked out?
The problem you describe is known as brake fade which can occur when brake oil may vaporise on absorbing heat at the pads. This usually occurs when either brake oil has degraded with age or has gotten contaminated. Regular Brake oil replacements are required as the boiling point of prake oil is reduced by the moisture it entrains. After a few years brake oil may contain upto several percent water.
If hill descend requires third gear then it is not that steep at all and your brakes should not be overheating. Get them checked.

Last edited by bullrun87 : 5th June 2016 at 11:25.
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Old 5th June 2016, 17:00   #248
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Re: Brake fluid overheating in hill driving

Hi, how did you come to a conclusion that your brake fluid overheated? If you meant by a hard and non responsive pedal, it's because the brakes have faded. Happends when the brakes dont have enough time to cool down, between application.

Solution: Well, technically you should be driving down an incline in the same gear you drove up. Preferably, one lower.

Last edited by dhanushs : 5th June 2016 at 17:03.
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Old 5th June 2016, 22:03   #249
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Re: Brake fluid overheating in hill driving

Quote:
Originally Posted by v_2rahjo View Post
So I don't think it's the brake fluid but the brake pads which over heated and lost their grip due to over usage. Are you riding the brake while doing down? You might want to shift to an even lower gear to limit the usage of brakes
Quote:
Originally Posted by humyum View Post
Do you keep the brakes continuously pressed or you press them say for a second or two and let them go when you have to slow down on a downslope?

The second option gives the brakes heat dissipation time, and what you are facing is the brake pads overheating, not the brake fluid.
Quote:
Originally Posted by bullrun87 View Post
Buddy I have driven downhill on a variety of hills of varying steepness but have never faced this issue. Could it be that you used third gear when instead you should have used second and as a result were riding the brakes? How do you know for sure that the problem occured only due to overheating brake fluid? Did you get the brake pads and the rest of the system checked out?
The problem you describe is known as brake fade which can occur when brake oil may vaporise on absorbing heat at the pads. This usually occurs when either brake oil has degraded with age or has gotten contaminated. Regular Brake oil replacements are required as the boiling point of prake oil is reduced by the moisture it entrains. After a few years brake oil may contain upto several percent water.
If hill descend requires third gear then it is not that steep at all and your brakes should not be overheating. Get them checked.
Quote:
Originally Posted by dhanushs View Post
Hi, how did you come to a conclusion that your brake fluid overheated? If you meant by a hard and non responsive pedal, it's because the brakes have faded. Happends when the brakes dont have enough time to cool down, between application.

What I meant by brake pedal being dead was... The pedal was completely free as if nothing is attached to it. Though I press the brake pedal, I couldn't feel like I am pressing the brake, it was that free.

I know that my front brakes are disc brakes and rear ones are drum type. I would like to understand how both will get heated at the same time and both going ineffective at the same time..
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Old 5th June 2016, 22:35   #250
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Re: Brake fluid overheating in hill driving

Quote:
Originally Posted by sriramaero View Post
What I meant by brake pedal being dead was... The pedal was completely free as if nothing is attached to it. Though I press the brake pedal, I couldn't feel like I am pressing the brake, it was that free.
There is : Air in your system. You need to bleed it. Or, there is a leak in your master cylinder. However hard you use the brakes, the pedal wont give up.
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Old 5th June 2016, 22:40   #251
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Re: Brake fluid overheating in hill driving

Quote:
Originally Posted by sriramaero View Post
Guys,
I am a frequent hill climber and while descending down, the thumb rule says to descend in 3rd gear or so, depending upon the steepness. I believe that this would act as engine braking rather than using the car brakes completely.
While descending the thumb rule is to use the same gear that had been used while ascending. Even then for steep slopes for cars with tall first gear you may still need to tap the brakes. If you feel you have been using a lot of braking, please take frequent breaks to cool down the brakes. What you faced is most probably brake fading. Even then get the brakes checked at the service centre once.
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Old 5th June 2016, 23:33   #252
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Re: Brake fluid overheating in hill driving

Quote:
Originally Posted by sriramaero View Post
Guys,

I am a frequent hill climber and while descending down, the thumb rule says to descend in 3rd gear or so, depending upon the steepness. I believe that this would act as engine braking rather than using the car brakes completely.
Glad that you are safe.

For starters, your thumb rule is Wrong!!! The thumb rule of driving on the hills is "Drive down in the same gear in which you climbed". If while climbing you used 2nd gear in a particular incline, you have to climb down in 2nd gear.

You seem to be riding the brakes while driving down the hill. This has over heated the brake discs and have made the brakes ineffective. Never do that. Use engine braking as mich as possible and do not rush while driving down the hill.

Drive Safe.
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Old 5th June 2016, 23:43   #253
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Re: Brake fluid overheating in hill driving

Quote:
Originally Posted by sriramaero View Post
What I meant by brake pedal being dead was... The pedal was completely free as if nothing is attached to it. Though I press the brake pedal, I couldn't feel like I am pressing the brake, it was that free.
Let me assure you that a hydraulic assembly is very, very reliable.. at least for the most part barring a few circumstances. Heat has very little or nothing to do with this. Hydraulics are where mineral oils with a certain viscosity are used to create pressure within a chamber and to transfer the physical force into greater pressure thus making the human effort far lesser.

There are 2 sure ways that the failure will happen in the way you have described it 1) Leakage in the hydraulic chamber - if there is no oil to begin with there will be no hydraulics 2) Interference in the assembly - mechanics will always, always ignore clutch & brake line bleeding.. air gets into the pipes every so often and to maintain optimum hydraulic pressure and factory operating efficiency the lines have to be bled of the air so that there is only 100% oil running in the system and not flexible air-pockets which will give a frighteningly vague feel.
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Old 6th June 2016, 00:15   #254
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Re: Brake fluid overheating in hill driving

As the you say that the brake pedal was almost 'free', I would say that it is not brake fading. Please get your system checked. Or do this:
1. Start your car.
2. Press the brake pedal and hold it there.
3. If there is a leak in the system, your pedal will sink complety.
4. If the pedal sinks completely, you must get your brakes checked up.

Also, as others have said, descend downhill in the gear you would have climbed up. In this way, you will use brakes in a minimal way and that will avoid overheating.

Consider flushing the entire system if the fluid inside is over 2-3 years old. Refer to the manual to know the flushing interval of the brake fluid.

Regards

Last edited by saket77 : 6th June 2016 at 00:18.
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Old 12th June 2016, 05:44   #255
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Re: Brake fluid overheating in hill driving

Quote:
Originally Posted by sriramaero View Post
Why the manufacturer doesn't consider an option to override the hydraulic brakes with some kind of manual push-pull linkage under emergency situations ?
Did you try the handbrake? That is independent of any hydraulic system.

How did you stop the vehicle when you found the pedal going all the way to the floor?

I guess the last option would have been to force a downshift to 1st gear and graze the vehicle against the hill. It'll probably go into the rain water drain.

Still, better to come home embarrassed with a broken bumper, than silently in a black van.

Last edited by hangover : 12th June 2016 at 05:46.
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