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Old 12th December 2007, 14:06   #16
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I have heard that doing so puts lesser load on the transmission while starting up and hence less wear and tear. Dont know how far it is true. Whatever it is, there is a reason why it is mentioned in car manuals. I have following it since some time now.
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Old 17th February 2013, 22:51   #17
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Default Re: Palio 1.2 nv - Pressing the clutch pedal while starting the car

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Originally Posted by madan80 View Post
IMHO it does not make sense, if the car is in neutral - what load is there on the flywheel anyway?
I have been starting the car in neutral - idling it for about 1 minute and then moving.
This are exactly my thoughts.

I know this is an old thread, but it didn't make sense to start a new one as the question is not answered. Does depressing the clutch have the same affect on the engine/transmission as when the car is on neutral gear?
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Old 18th February 2013, 00:20   #18
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Default Re: Palio 1.2 nv - Pressing the clutch pedal while starting the car

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This are exactly my thoughts.

I know this is an old thread, but it didn't make sense to start a new one as the question is not answered. Does depressing the clutch have the same affect on the engine/transmission as when the car is on neutral gear?
Yes it does.
If you are in neutral and dont depress the clutch, you will be rotating the engine, flywheel, clutch, input shaft of transmission, all all the 5 synchromesh gears(Meshing and running). Only thing that is not rotating is the output shaft.
However pressing the clutch disengages the complete transmission side, but there is an additional force. The friction between flywheel & clutch. But IMO there is still a minute benefit if you are depressing the clutch.
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Old 18th February 2013, 00:34   #19
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Default Re: Palio 1.2 nv - Pressing the clutch pedal while starting the car

Disengaging the clutch reduces the load on the starter motor while cranking as only the engine cranks without the gearbox. Reduced load translates to better life of the starter motor and the battery. On the safety aspect, inadvertent in-gear cranks can be made safely as the clutch is disengaged. Overall, a good practice and I personally follow it.
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Old 18th February 2013, 08:11   #20
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Default Re: Palio 1.2 nv - Pressing the clutch pedal while starting the car

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Originally Posted by oxyzen View Post
Yes it does.
If you are in neutral and dont depress the clutch, you will be rotating the engine, flywheel, clutch, input shaft of transmission, all all the 5 synchromesh gears(Meshing and running). Only thing that is not rotating is the output shaft.
Is there a video or an animation that you've come across that clearly explains this? I've searched how stuff works, but couldn't find something that explains this part clearly.

Also, in the statement above, you've mentioned that the engine is rotating. This happens even if the clutch is depressed or not.
As these components are freely rotating, there shouldn't be any additional strain on the starter. Like you said... if there is any difference, it's a minute one. But minute enough for me to start depressing the clutch when starting the car.
Come to think of it, the micro hybrid starts the car when the clutch lever is depressed. So it may be a good practice after all.

Last edited by triedeverything : 18th February 2013 at 08:15.
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Old 18th February 2013, 09:49   #21
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Default Re: Palio 1.2 nv - Pressing the clutch pedal while starting the car

The whole reason companies recommend depressing the clutch when you start is that it ensures the vehicle is in neutral irrespective of whether you put the gearshift in neutral, there is a fault with the gear lever and it is stuck in a gear, you forgot to put the vehicle in neutral because you were in a hurry etc.

Last edited by pganapathy : 18th February 2013 at 10:05.
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Old 18th February 2013, 10:34   #22
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So the conclusion is that its a good practice that prevents accidental damage.
Something like idling the turbo.there the goal is to not engage the turbo after starting or shutting down - idling ensures that.

So depressing the clutch is a protocol to be implemented for all drivers with varying experience and /or mechanical empathy .its a good practice to implement especially if you're not the only driver of your car.


Am I correct?
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Old 18th February 2013, 11:11   #23
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Thanks pganapathy. I think it is a simple reason as that. But I always had this question in mind. The clutch is surely a mysterious engineering piece that I ve tried understanding over several websites. But then came the dual clutches and what not! That sent all my learning through the window.

But I ve read on another automotive forum that the procedure minimizes the load on the starter motor by disengaging the transmission from the starter motor which in turn reduces load on battery. Does that make sense?

OT query but since this thread is about clutches, it may be worthwhile posting this here. For instance a redsignal at abiut 500m away and you know you need to come to a stop from say 70kmph. Whats the ideal procedure? There is braking and then engine braking. And then of late I ve found myself doing something subconsciously. I depress clutch pedal and coast to the point decelrating and then use the brakes to come to a full stop. Can this be termed as riding the clutch?

Last edited by mempheS.D : 18th February 2013 at 11:14.
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Old 18th February 2013, 11:40   #24
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Default Re: Palio 1.2 nv - Pressing the clutch pedal while starting the car

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Originally Posted by mempheS.D View Post
Can this be termed as riding the clutch?
Riding the clutch is when you keep one foot on the clutch and exert some pressure on it (usually absentmindedly, in anticipation of a gear change, or a stop) What you are doing is not riding the clutch. But neither is it good for your brakes. You want to use whatever resistance is offered by the engine to slow down and then stop. By depressing the clutch, the car moves at a much faster rate (since it is rolling without any resistance) and to stop, the brakes are applied to wheels that are rotating at a higher rpm. Instead, don't depress the clutch as soon as you know you are going to stop. In the scenario above, take your foot of the accelerator as soon as you know you have to stop, but don't depress the clutch yet. Allow the car to slow down while it is in gear. Just before you start to think that it will stall... press the clutch and change the gear and then apply brakes.
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Old 18th February 2013, 22:12   #25
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Default Re: Palio 1.2 nv - Pressing the clutch pedal while starting the car

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Originally Posted by triedeverything View Post
Is there a video or an animation that you've come across that clearly explains this? I've searched how stuff works, but couldn't find something that explains this part clearly.
Nope. I Just happen to be in the business.

Quote:
Originally Posted by triedeverything View Post
Also, in the statement above, you've mentioned that the engine is rotating. This happens even if the clutch is depressed or not.
Engine is always rotaing. In Neutral / while clutch is depressed, it is rotating at idle RPM which is around 800 RPM in steady state. The engine stops rotating only when you switch off the engine.


Quote:
Originally Posted by triedeverything View Post
As these components are freely rotating, there shouldn't be any additional strain on the starter.
Even freely rotaing components contribute to friction although it may be minute. Friction in bearings, meshing of gears (5 synchromesh gears) etc.
Do search for working of a gearbox, it will clear your concept quite a lot.

Quote:
Originally Posted by triedeverything View Post
Like you said... if there is any difference, it's a minute one. But minute enough for me to start depressing the clutch when starting the car.
Come to think of it, the micro hybrid starts the car when the clutch lever is depressed. So it may be a good practice after all.
In older cars these losses can be quite significant. In neutral some cars have a whining sound that goes away when the clutch is depressed. I am not sure about microhybrids but it is a good practice to depress the clutch. And if you do that, you dont even need to shift to neutral. Technically makes no difference.



Quote:
Originally Posted by mempheS.D View Post
Whats the ideal procedure? There is braking and then engine braking. And then of late I ve found myself doing something subconsciously. I depress clutch pedal and coast to the point decelrating and then use the brakes to come to a full stop. Can this be termed as riding the clutch?
The ideal way is to leave the accelerator and let the car stop. If needed apply brakes and/or downshift. However if you are doing ~4000 RPM you should avoid downshifting as the can lead to catastrophic damage. Read over revv.
In my opinion, clutch should be used only during changing gears. Rest everything is clutch riding.

The worst nightmare of a clutch is half clutch and high rev. Bottom line, the lesser you touch the clutch pedal the better.

Last edited by oxyzen : 18th February 2013 at 22:23.
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