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Old 18th May 2011, 22:30   #31
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Default Re: Emergency driving - Without clutch

@Sudev & Dkg >> The techniques mentioned by you are similar to driving the old school buses and trucks where one had to double clutch for every gear change, up or down. The idea remaining the same here to bring the revs to match only difference here is that we are discussing a failed clutch.

The sweet spot you speak about in the rev range is similar to clutchless up & down shifting on a bike. Point is to be in tune with your vehicle to know just 'when to'.
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Old 18th May 2011, 23:48   #32
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Default Re: Emergency driving - Without clutch

Quote:
Originally Posted by sudev View Post
Please contribute more.
Methinks DKG has explained it better than I ever could!

Regards
Sutripta
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Old 19th May 2011, 00:17   #33
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Default Re: Emergency driving - Without clutch

Hello everyone!

Very detailed and intresting discussion indeed.
For those who need pictorial refrence try - www.howstuffworks.com > Automotive section.

I have personally experienced fading clutch in my 19yr old Padmini while on a Long drive - http://www.team-bhp.com/forum/travel...r-padmini.html (1400 Kms in 18 yr old Premier Padmini)

Since clutch plate was hard to find , i dragged my car till kolhapur.
Flywheel was scratched as per mech, had to replace the Clutch plate and pressure plate.

Any TIPS for drives when you feel Clutch is slipping and you have long way to go?

I have heard some mechs putting some thread or some material to increase the Friction.

Experts please comment.
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Old 19th May 2011, 01:33   #34
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Default Re: Emergency driving - Without clutch

Quote:
Originally Posted by silverado View Post
Any TIPS for drives when you feel Clutch is slipping and you have long way to go?
Do not allow the clutch to heat up. ie, do not slip the clutch.

Also, be gentle on the clutch, ie, no sudden take off's. Also, try to avoid sudden accelerations with pedal to metal et al.

Be gentle on the right foot too. In short, drive as if you are driving for the best FE contest.
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Old 19th May 2011, 01:44   #35
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Default Re: Emergency driving - Without clutch

@Dhanush

Im talking about the roads which is a mix of small hills and plain roads.
Also in situations when you have a full load of passengers?

I was lucky to have a Jeep following my padmini with my family in it, while i alone kept her in 1st gear for nearly 30 odd minutes and 9kms while climbing the Gaganbavda Ghat in Maharashtra.

Also after that i made it to Kolhapur which was a good 55 kms with mix section of road levels, ie there were small hill sections as well which were a challenge.

So the question is - What would some one do if you realise your clutch is slipping and you dont find a new clutch plate easily wherein you might have to drive for reasonable distance ( 40-50kms can be a real challenge is such conditions) to reach a Town/City to get one.

I want to know a TEMP fix which can be carried out ( By a mech ) in such situations so that you can drive normally.

Of course you would be taking precautions as you have mentioned already in such situations.
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Old 19th May 2011, 01:47   #36
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Default Re: Emergency driving - Without clutch

Thanks for the great discussion.
I have a doubt regarding something I do during regular driving.

As you guys mentioned, the gear shifts out into neutral very freely (without the clutch depressed) once the accelerator is released.

Often while driving in the city, when there's an open straight stretch of road ahead of me (people who've driven in Chandigarh will know what i'm talking about). So I accelerate upto 60-70 Km/H and shift into neutral without pressing the clutch.

My question is, am I damaging my car by doing this?

For the record, the clutch in my last car lasted for >100000 Kms (Sold it after that) and the one I have right now has clocked almost 60000 Kms without any replacements.
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Old 19th May 2011, 02:08   #37
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Default Re: Emergency driving - Without clutch

@Sugam

Without Depressing clutch if the gear changes happen , then TEETH have worn out and there must be considerable PLAY in the gearbox, is slots will not be PERFECT.

You get to see many all OLD Padmini Taxis in which you can shift in such manner.

Also many State Transport bus drivers do the same on Old buses.
I guess you are damaginig the Gear selector by doing so.
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Old 19th May 2011, 04:50   #38
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Default Re: Emergency driving - Without clutch

@Sugam : Re. shifting to neutral without clutch - I think not. The problem area is gear engagement and not disengagement. If there is no "load" one can shift without pressing clutch without harm. Load here mean acceleration or de-acceleration while doing this.

Professori jee do I pass?????
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Old 19th May 2011, 08:01   #39
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Default Re: Emergency driving - Without clutch

Quote:
Originally Posted by sugam View Post
shift into neutral without pressing the clutch.
...am I damaging my car by doing this?
Quote:
Originally Posted by silverado View Post
Without Depressing clutch if the gear changes happen , then TEETH have worn out and there must be considerable PLAY in the gearbox, is slots will not be PERFECT.
What Silverado says is correct. With the clutch engaged regardless of whether you are accelerating or coasting the gears are in mesh and driving each other. In such a situation when gears are being pulled apart the teeth are scraping against each other more forcefully than when the clutch is disengaged. Further the gear selector moves a gear along the main shaft splines and if this is done in stress when gears are driving each other then you end up slowly grinding the splines too, not to mention spoiling the selector mechanism too. Over time both the gear teeth and the splines will wear out as a result of the practice and your selector will develop more play. Obviously your clutch is not affected so while its lasting longer the health of the gearbox is being slowly compromised.

You will notice that gears pull apart with some resistance when you don't press the clutch in as compared to when you shift out with the clutch pressed in. That resistance is basically the teeth catching onto each other and over time it will wear teeth out

So please always use the clutch to shift out of a gear should you desire to coast in neutral.
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Old 19th May 2011, 22:51   #40
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Default Re: Emergency driving - Without clutch

Quote:
Originally Posted by sudev View Post
@Sugam : Re. shifting to neutral without clutch - I think not. The problem area is gear engagement and not disengagement. If there is no "load" one can shift without pressing clutch without harm. Load here mean acceleration or de-acceleration while doing this.
Disengaging: Let the car be under power. Firm hand (not with all your strength!) trying to push gear into neutral. Release throttle. Should pop out of gear (will happen when power is not being transmitted in either direction.

Engaging: You have to match speeds. Else you'll a) hear a grating sound b) Fill your gear oil with metal particles c) If you are brutal enough to still engage a gear, high chance something somewhere will give way.

Double declutch with the clutch. Even in a synchro box, there is a very definite qualitative difference to the shift feel when one gets it right. Should prepare one for clutchless gearchanges, without damaging anything.

Sudevji, you know you are right!

@ DKG. Constant mesh gears. It is the dogs which slide.

Regards
Sutripta
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Old 19th May 2011, 23:08   #41
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Default Re: Emergency driving - Without clutch

I had a crazy and really wild experience with this issue. This is about 15 years back. I had gone for a nice drive with my lady friend to the hills in my Contessa fitted with a diesel engine. As luck would have it, while returning to Chandigarh the clutch wire snapped about 40 kms from Chandigarh near Dharampur. I had to get back my lady friend or it wouldn't have mattered. I put the car in 3rd gear and cranked it. Fortunately for us the car started and traffic too was ok types. Believe you me I did those 50 kms stalling the car just twice and only in 3rd gear. Was too scared to change gears. Third stall was about 100 m from her place and finally got the the clutch wire changed the next day for Rs. 200 + labour. Thank goodness for the new battery!
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Old 20th May 2011, 00:06   #42
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Default Re: Emergency driving - Without clutch

Before someone points out, let me ask the most vital question. How does one stop his vehicle when he does emergency driving - without clutch?
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Old 20th May 2011, 06:47   #43
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Default Re: Emergency driving - Without clutch

@Sae90 : Shift to neutral and apply brakes.
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Old 20th May 2011, 08:04   #44
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Default Re: Emergency driving - Without clutch

Quote:
Originally Posted by Sutripta View Post
Constant mesh gears. It is the dogs which slide.
true. in the older simpler gearboxes first and reverse were engaged by a sliding gear, the image of which seems embeded in my memory
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Old 20th May 2011, 15:01   #45
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Default Re: Emergency driving - Without clutch



WOW. I am surprised to see so many cases of folks getting stranded owing to a clutch failure ....... and here I was thinking my Linea was the only one that ditched me.

I experienced the clutch issue very very recently. The slave cylinder was busted.

Here's a little snippit from my Linea's ownership thread:

"My foot got buried in the floor and the clutch refused to come back up. I panicked for a moment, But i quickly gathered my nerves and parked on the shoulder (FORCED the gear into neutral). I looked at the clutch. It was fully depressed and would not come back to its position. I pulled it out with my hand but the slightest tap of my foot on the clutch pedal sent it back into the floor.

I looked at my watch. It was around 4:35.

Ok, I need to act fast. The traffic will really start building up in less than 25 minutes.

I sat back into my seat, put on my seatbelt, slotted the car in 1st gear, Released the handbrake, put the key into the ignition slot and turned it.

The car jolted violently, but started. The car began to move veryyyyyyyy slowly. Ok, the traffic is not too dense now. Maybe I wont have to come to a complete halt, I thought.

It was a pain to drive the car in 1st gear, even for 500 meters. I pulled over to the side of the road again and shut off the car. I started the car again, only this time, in 2nd gear. To my surprise, the car started once again (albeit with a LOT more jerks). Ok, this is slightly better now. The second gear has an 80 km range.

I got stuck again at the DND toll plaza but moved along and was finally home."

(More details of the issue, resolution and cost here - http://www.team-bhp.com/forum/long-t...-review-7.html (Linea 1.4 (E+) - 1 year ownership review))

To whatever has been said on this thread already, I would like to add that whilst driving in the condition as described above, I believe it would be prudent that you turn off the Aircon, as chances of the car overheating would increase(??).

Quote:
Originally Posted by Sutripta View Post
Disengaging: Let the car be under power. Firm hand (not with all your strength!) trying to push gear into neutral. Release throttle. Should pop out of gear.
Totally agree. Experienced this myself. In the situation above, I tried engaging the 2nd gear (sans clutch of course). Although i could not slot the 2nd gear, the movement to neutral from 1st was much easier. It did require some effort though.

Last edited by Urban_Nomad : 20th May 2011 at 15:03.
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