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Old 21st May 2011, 13:44   #16
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Default Re: Emergency driving - Without brakes

{offtopic}

Power-assisted steering, on a small to mid-sized car, is just a luxury, and is only really felt at parking speeds. I have no muscle: when I first parked my late mother's tiny Micra, with no power steering, I thought, "How did an 89-yr-old manage this?" Two days later I wasn't even noticing.
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Old 21st May 2011, 14:37   #17
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Default Re: Emergency driving - Without brakes

Quote:
Originally Posted by gotzuk View Post

I would like to mention here that all modern cars run diagonal braking circuits, which separates the braking circuit right from the brake booster, which even in case of total failure of one circuit will provide you enough braking force to stop the vehicle.
A small correction. All cars have dual circuit in the Brake system, not all have diagonal split, some have "H-type" circuit also. The failure in a "X / diagonal type" circuit becomes more pronounced as braking on the RH and LH side would be different.

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Old 22nd May 2011, 14:40   #18
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Quote:
Originally Posted by YaeJay View Post
Have you experienced it yet? The 6 lane highways you talk about are pretty recent. And these are not stunts. Once you experience your first moment, you will realize the true meaning.
Well, I was fortunate enough to manage without dashing into someone when my Indigo left me stranded without brakes or PS (the PS pump failed which also powers brakes i guess). And I've had a little share of driving a manual steering Santro, but its not the same with heavier/bigger cars. For those in Bangalore would know the traffic on Marathalli bridge as soon as you get down at the HAL end after an empty bridge where you gain speed. I can tell you that managing it through that rush without PS and without brakes needed a lot of prayers.

To my luck, the handbrake worked, though the stopping distance isnt anything to talk about, it atleast got the vehicle down to speeds where even I'd bumped into people nobody would have gotten hurt seriously.

Quote:
Originally Posted by YaeJay View Post
There are cars without power steering even in this age! And there are a few of us that still like the feed back from such sets of wheels. When you have absolutely no brakes, ( who said you always have to loose them on a 6 lane highway?) even 10 km/hr can feel really fast.

Unless one is on a boat, most cars can steer clear without PS.
Well, imagine my wife driving the safari and this happens. Do you think she'll manage fine with manual steering? When you talk of a few who've lived through the manual steering age, I guess there are most new drivers who havent tasted it even on smaller cars, let alone the big wheels. I'm sure the Safari would be fun to drive without PS for you, but for me it would mean a disaster. So generalizing may not be a good thing in this case.

My point was that changing too many variables during an emergency adds to the panic which is what we dont want to have in a situation when your brakes are out. Lets put it this way, switching off the engine knowing that PS would go away and being able to steer successfully may be a good option for a seasoned driver.
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Old 22nd May 2011, 17:06   #19
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Default Re: Emergency driving - Without brakes

On anything less than a truck, I'd bet you wouldn't even notice the absence of power steering, until the vehicle was going slow enough that hitting something wouldn't do that much damage.

Getting back to the stopping issue: some say judder to a halt in 1st gear (engine running) and others suggest turning off. Leaving out the ancillary issues, although potentially engaging the steering lock is a very serious one), which f these two do people favour?

I'm with leaving the engine running and changing down, although that is only a gut feeling.

By the way, I can't believe no one suggested this, but, just in case they didn't: try to find a turn or place where you can make the car face up-hill!
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Old 22nd May 2011, 20:14   #20
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Default Re: Emergency driving - Without brakes

Sorry to be missing after starting the topic. Just felt like a drive today so went to Kasauli and back. Nothing like nice long drive to relax and catch up on life with your better(?) half.

On the way up we passed a spot between Parwanoo and Chakki Mor (those who know the area would be able to relate and for others this is few km's after start of hill climb when going to Simla) where almost 20 years back both of us experienced a brake failure driving a Standard 2000 downhill at pretty brisk pace. Just yesterday I was describing this thread to her and at time we had no plans to do this drive today. When we passed that area she just gave me a smile.

I think I have written about this elsewhere but in brief we, me and cousein, were mildly "racing" downhill in a convoy of cars ranging from M800 to Gallant To Corolla and a Standard 2000. I was driving the last and was last trying to catch up with others. When brakes failed I did all the actions as I described at the start of thread. PLUS used handbrakes only during the straight lines.

Now Standard 2000 was a heavy car but I switched off ignition only at the last moment when wanting to come a full stop. While shifting down the engine was engaged and so power assist was available. IMHO even when you do switch off ignition the rotating engine will keep driving the old type hydraulic power assist due to belt drive.

Again let me say switch off is only the last step when you are down to lowest speed the first gear is able to get to.

Most important use hand brakes with great caution - I know panic and all that - but if you do this without thinking you can end up in worst trouble.

And excellent inputs by others.
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Old 22nd May 2011, 21:31   #21
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Default Re: Emergency driving - Without brakes

Quote:
Originally Posted by sudev View Post
Now Standard 2000 was a heavy car but I switched off ignition only at the last moment when wanting to come a full stop. While shifting down the engine was engaged and so power assist was available. IMHO even when you do switch off ignition the rotating engine will keep driving the old type hydraulic power assist due to belt drive.

Again let me say switch off is only the last step when you are down to lowest speed the first gear is able to get to.

This is something I forgot to mention! I guess everyone forgot to mention.
The key is try not to panic. I have said that in a similar thread elsewhere.



Quote:
Originally Posted by Thad E Ginathom View Post
O

Getting back to the stopping issue: some say judder to a halt in 1st gear (engine running) and others suggest turning off. Leaving out the ancillary issues, although potentially engaging the steering lock is a very serious one), which f these two do people favour?

Steering lock happens only when one pulls out the key and just like sudev pointed out, one needs to turn off the ignition at the very last moment when enough speed is lost.

I'm with leaving the engine running and changing down, although that is only a gut feeling.

That is actually what we meant, once in lowest possible gear turn off the engine!

By the way, I can't believe no one suggested this, but, just in case they didn't: try to find a turn or place where you can make the car face up-hill!
Yes, that is a good suggestion. In most cases we all tend to think much faster at situations like this and ofcourse all this seems to be in slow motion

A lot depends on what,who, when and where. There is no fail safe method. its just the experience of a few fortunate ones (to be alive) to probably reduce the panic?

Quote:
Originally Posted by amolpol View Post
Well, imagine my wife driving the safari and this happens. Do you think she'll manage fine with manual steering? When you talk of a few who've lived through the manual steering age, I guess there are most new drivers who havent tasted it even on smaller cars, let alone the big wheels. I'm sure the Safari would be fun to drive without PS for you, but for me it would mean a disaster. So generalizing may not be a good thing in this case.

My point was that changing too many variables during an emergency adds to the panic which is what we dont want to have in a situation when your brakes are out. Lets put it this way, switching off the engine knowing that PS would go away and being able to steer successfully may be a good option for a seasoned driver.
Amolpol, point taken! Ask her to join the forum!

Last edited by YaeJay : 22nd May 2011 at 21:34.
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Old 22nd May 2011, 22:37   #22
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Default Re: Emergency driving - Without brakes

One more point people. Usually, You dont lose the brakes all of sudden. It happens gradually. So when you realise that the brakes have failed, dont just forget about them. You may still have little braking available. So keep pumping the brakes. It will help you lose some speed.

One of my experience...
Back in 1996, I was just 9 and was seated in my Mothers lap in the passenger seat of our Premier Padmini. We were going to Banglore on the beautiful open Bangalore highway. My Dad was driving and we were doing around 80kmph. There was a Toll booth in the way and my Dad applied the brakes to slow down, but they did not work. He managed to get it in 3rd and lose some speed but by then the toll booth was just about 10 meters away. At this point, we were doing around 70, the toll booth gate was closed and many vehicles were waiting ahead of us. The gate on the right side (wrong side) was partially open and there was just enough space for the car to pass through. Dad swerved the car at that speed to the right narrowly missing cars ahead and aimed at the open space. The toll guy thought we were trying to flee without paying and ran in our way. He managed to save himself and we fortunately escaped. Then the engine braking was employed to slow down the car. If there were oncoming vehicles, or if the other gate was shut, that would had been a disaster. Dads presence of mind and a Great Luck saved the day. The reason of the failure was diagnosed to be oil leakage. Though this is an old incident, its still vivid in my memory.
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Old 23rd May 2011, 10:16   #23
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Default Re: Emergency driving - Without brakes

Point well made - evasive manoeuvres are essential and can add to your probability of escaping unhurt or damage to car.

Brakes may fade or fail. Gradually or all of a sudden. Double circuits makes them more reliable. But the point I am making is that be prepared and chances are you'd live to tell the tale.

RECOMMENDED EXPERIMENT #1:
Drive on at your usual speed and try stopping to standstill using downshift etc. and without touching brakes. Treat the brakes as back up. Usual caveat about doing this in an open patch of road applies.

RECOMMENDED EXPERIMENT #2:
Repeat the above but use hand brake only and no gear down shifts. Modern cars have pretty efficient hand brakes but stopping a car just using hand brakes will show you while they have good grip the actual stopping distance is much more. Reason? Brakes are being applied to two wheels only. Weight transfer to front wheels means lesser "grip" from the rear tyre.

Last edited by sudev : 23rd May 2011 at 10:18.
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Old 23rd May 2011, 19:19   #24
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Default Re: Emergency driving - Without brakes

I have heard that Tavera is not very reliable with the brakes. If its only belt snaps, the brake booster and the power steering fail. It has no backup belt. The driver gets a double blow.
Is this true?
The Tavera also has suspension issues. The front suspension usually fails.
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Old 23rd May 2011, 19:32   #25
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Default Re: Emergency driving - Without brakes

Excellent thread-very useful. Rated 5*

I have slightly naive question: in a well-maintained car (serviced every 6 months and all niggling replacements etc. made) is brake failure a real possibility? I always associated failed brakes with run-down or badly maintained cars. How real is the threat that my brakes may fail?
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Old 23rd May 2011, 19:44   #26
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Default Re: Emergency driving - Without brakes

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Originally Posted by noopster View Post
Excellent thread-very useful. Rated 5*

I have slightly naive question: in a well-maintained car (serviced every 6 months and all niggling replacements etc. made) is brake failure a real possibility? I always associated failed brakes with run-down or badly maintained cars. How real is the threat that my brakes may fail?
Yes. Brakes of any car can fail. I have had two experiences on my two perfectly maintained cars. One was with Premier, and the other one was with Santro. There was a leakage in the rear brake cylinder of the Santro. The brakes of the Santro did not fail completely though and I could drive it io the service station. Then there were other two instances I have come accross where my friends faced the situation on their Maruti's. These thing happen quite regularly.
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Old 23rd May 2011, 20:27   #27
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Default Re: Emergency driving - Without brakes

@noopster : Thanks for the rating. Brakes can fail. Period. Statistically very very rarely nowadays.

TO BE DONE CAREFUL EXPERIMENT #3:

Repeat the experiment #2 but this time instead of doing it in straight line do it while taking a corner or doing steering manoeuvres. Watch for the rear end slide out and be prepared to control it. Do not do this at very brisk pace.

If you do the three experiments you get fair idea of what to expect when a brake failure occurs. Hand brake only braking distance increases and it is also important to apply handbrake with release button firmly under control. This way you will not accidentally lock the rear wheels.

The last one also gives you idea of what can happen if you are using handbrakes very aggressively.
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Old 23rd May 2011, 20:42   #28
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Default Re: Emergency driving - Without brakes

I have observed that the tow guys tow guys tow away cars when the hand brake is still applied.I guess this will screw up the rear brake liners and will cause a loss of braking power. What do you think about that?
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Old 23rd May 2011, 20:45   #29
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Default Re: Emergency driving - Without brakes

@TI : You are letting the cat out of bag. In the triology about Emergency Driving that wil get covered under the next thread.
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Old 24th May 2011, 05:54   #30
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Default Re: Emergency driving - Without brakes

Now adding a twist to the tale.

Down shifting is the most recommended option. Now how to down shift and stop an Auto Transmission car with No brakes.
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