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Old 17th May 2011, 20:07   #31
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Re: Scorpio Mhawk Clutch Failure & Break Down

@behramji

I understand what I am saying and I am not in any way suggesting that your dept is not going a great job. But I am almost certain that there are some people asleep at the wheel in Mahindra and I really cannot accept any logical reason for this failure besides poor design/quality control.

I don't ride the clutch at all even in the city I press the clutch only when the engine will start knocking... Besides the clutch plates are still in good condition and I don't expect to change them for a while.
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Old 17th May 2011, 20:07   #32
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Re: Scorpio Mhawk Clutch Failure & Break Down

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Originally Posted by Guderian View Post
And now to think that the clutch slave cylinder is inside the bell housing ! Can be quite a nightmare changing that. Possibly the design change was carried out to protect the slave cylinder and reduce the number of components ? As the regular complaint was the rubber bellows tearing and water entering the same, the actuators rusting and the pedal turning hard and the gear changes impossibly tough.
Dear Guderian - the design of clutch slave cylinder inside the bell housing is very normal, we have not reinvented the wheel. Look at so many passenger cars, you will find this design. It would be correct to carry out an analysis and come to a conclusion. Please leave it to us to do it, it's our job. I trust that you will understand and appreciate.

Dear Tanveer - you may believe or not believe, just as an example, I was testing one of our life test vehicles which had covered 1,36,600 kms with the original clutch working perfectly. Even the pedal effort was perfect. Obviously I cannot divulge the vehicle configuration. Obviously this indicates a variance for which root cause analysis / FMEA (Failure Mode Effect Analysis) needs to be carried out. And, by the way, Luna tyres will not take the speed of the Bugatti Veyron! .

Best regards,

Behram Dhabhar

Last edited by benbsb29 : 17th May 2011 at 20:31. Reason: Fixed broken quote tag.
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Old 17th May 2011, 20:14   #33
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Re: Scorpio Mhawk Clutch Failure & Break Down

My 2002 Indica had the factory clutch at ~1,50,000kms when i sold it in 2007. It was only me and Dad who drove this car.
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Old 17th May 2011, 20:56   #34
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Re: Scorpio Mhawk Clutch Failure & Break Down

Tini, I had requested you for the pics of changed parts. Is it available with you? If yes please post here.

Spike
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Old 17th May 2011, 21:08   #35
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Re: Scorpio Mhawk Clutch Failure & Break Down

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Originally Posted by SPIKE ARRESTOR View Post
Tini, I had requested you for the pics of changed parts. Is it available with you? If yes please post here.

Spike
Sorry mate. Driver didn't have a camera with him. I will pick up the bill & used parts on my way back to chennnai and give you the pics & part numbers.
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Old 17th May 2011, 21:21   #36
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Re: Scorpio Mhawk Clutch Failure & Break Down

Quote:
Originally Posted by DHABHAR.BEHRAM View Post
Dear Guderian - the design of clutch slave cylinder inside the bell housing is very normal, we have not reinvented the wheel. Look at so many passenger cars, you will find this design. It would be correct to carry out an analysis and come to a conclusion. Please leave it to us to do it, it's our job. I trust that you will understand and appreciate.
Hi Behram, All that is appreciated for sure no doubt. But I am sure you wouldn't grudge another auto lover and a user of the product the pleasure to analyse something and come to his or her conclusions !

One that has come after going through rough experiences of standing on the shopfloor of the ASCs and getting work done or seeing the vehicle and the work being really buggered up, one that has come from finding the Clutch Slave Cylinder or the Master Cylinder or the various other components give up under your feet after just a few thousand KMs. I am sure one needn't recount all the horror stories one has gone through at the ASC to get the folks there to understand what has gone wrong with the clutch and how and then trying to ensure that a proper work is done !

I am sure that it may be there in quite a few other vehicles, equally there are other vehicles without this design as well. Each design brings its own positives and negatives, I am sure, as everything else in life !
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Old 17th May 2011, 21:37   #37
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Re: Scorpio Mhawk Clutch Failure & Break Down

Quote:
Originally Posted by DHABHAR.BEHRAM View Post

Dear Tanveer - you may believe or not believe, just as an example, I was testing one of our life test vehicles which had covered 1,36,600 kms with the original clutch working perfectly. Even the pedal effort was perfect. Obviously I cannot divulge the vehicle configuration. Obviously this indicates a variance for which root cause analysis / FMEA (Failure Mode Effect Analysis) needs to be carried out. And, by the way, Luna tyres will not take the speed of the Bugatti Veyron! .

Best regards,

Behram Dhabhar
Dear Behram, I understand what you mean, but does your life test vehicle go through uphill traffic jams on flyovers on a daily basis.
Does it crawl through traffic so slow that if you are in first gear idle, you will hit the vehicle in front unless you press the clutch half way.
Or does it travel on uphill roads so bad, that you can't maintain enough speed so as not to stall the vehicle.
These are real world conditions. If your vehicle clutch lasts 350000kms inspite of driving in these conditions daily. hats of to you and your vehicle.
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Old 17th May 2011, 21:50   #38
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Re: Scorpio Mhawk Clutch Failure & Break Down

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Originally Posted by DHABHAR.BEHRAM View Post
Dear 4*4 addict - your comments are correct but what can I also say? If I was living in a lab like a white-coated professor, I would not be on the forum answering your questions, neither would I have given you the Thar CRDe. Without our confidential lab reports, your vehicle would not be on the road as the engineering BOM (Bill Of Materials) would not have been uploaded in our system and without the BOM, Nasik plant cannot roll down the vehicle. Please understand that I very well know how the "field" (real world) works. I trust you will appreciate.

Best regards,

Behram Dhabhar
I am sure we all believe in the robust design but the problem is sometimes its the cost cutting leading to variations from the original specs, other times its the vendor not paying attention to the quality and then we always have the bad QC in the stores.

Thats where we lack, from the drawing board to the production lines, things change.
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Old 17th May 2011, 22:35   #39
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Re: Scorpio Mhawk Clutch Failure & Break Down

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Originally Posted by tsk1979 View Post
Dear Behram, I understand what you mean, but does your life test vehicle go through uphill traffic jams on flyovers on a daily basis. Does it crawl through traffic so slow that if you are in first gear idle, you will hit the vehicle in front unless you press the clutch half way. Or does it travel on uphill roads so bad, that you can't maintain enough speed so as not to stall the vehicle. These are real world conditions. If your vehicle clutch lasts 350000kms inspite of driving in these conditions daily. hats of to you and your vehicle.
Dear Tanveer - we have what are known as DVPs (Design Validation Plans). They cover much more than what happens in what we call RWUP (Real World Usage Pattern). There are tests where the suspension has to be actually cooled after "unit distance / time" covered (cannot disclose figures) otherwise you will have shock absorbers snapping like matchsticks. There is a torque control test for the clutch where the vehicle front touches a wall and then the clutch is engaged. It is like an irresistible force striking an immovable object. Cool, isn't it? I am a vehicle test engineer. I test the living daylights out of test vehicles, I take them to limits and beyond, thrash them like nobody's business. Out there, I push it. It's my job.

I drive Nasik - Mumbai - Nasik very regularly in my Bolero / Thar. Our R&D drivers also use this road. When they see a certain brown souped up Bolero VLX / a black tweaked up Thar (both are blisteringly fast, believe me), they just move out of the way. These missiles just zoom past and are long gone before the passengers in their cars realize what just went. All these drivers know me, when we meet in Nasik R&D, we just smile. We know what we do. The clutches in both these vehicles are still absolutely OK.

Best regards,

Behram Dhabhar

IMPORTANT - PLEASE NOTE - test driving is not easy, neither is it glamorous as some people think. It needs attitude, rigor and top notch discipline. There is a difference between fast driving and rash driving. You can be as fast as you want, you should never be rash. You break this rule just once, you are history.

Best regards,

Behram Dhabhar
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Old 17th May 2011, 23:37   #40
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Re: Scorpio Mhawk Clutch Failure & Break Down

All I can say is that in the 2.70 lakh kms that I have covered, my Scorpio's clutch plate life has been exemplary and I have changed the slave cylinder only twice, the first under warranty at 50,000 kms and the second at 2,65,000 kms. I don't think it can get better than this.
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Old 18th May 2011, 06:06   #41
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Re: Scorpio Mhawk Clutch Failure & Break Down

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Originally Posted by DHABHAR.BEHRAM View Post
There is a difference between fast driving and rash driving. You can be as fast as you want, you should never be rash. You break this rule just once, you are history.
Brilliantly put DB.

Again I repeat clutch failing in 20000kms of stop go rush hour crawl traffic duty only is very likely than at 150000 of pure high speed highway use.
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Old 18th May 2011, 08:20   #42
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Re: Scorpio Mhawk Clutch Failure & Break Down

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Originally Posted by hvkumar View Post
All I can say is that in the 2.70 lakh kms that I have covered, my Scorpio's clutch plate life has been exemplary and I have changed the slave cylinder only twice, the first under warranty at 50,000 kms and the second at 2,65,000 kms. I don't think it can get better than this.
Dear Kumar - thank you for your comments, but I would state that "it does get better than this". Besides road evaluations, we are now in the process of vigorously pursuing a program which we have named "road to lab". The clutch pedal gets "operated" by a robotic "driver" as per a pre-determined cycle (again cannot share details) which simulates stop and go traffic for much more than what the real world usage pattern can ever throw at the vehicle. Therefore, I can confidently say that 3,50,000 kms is very much possible. I have already stated that customer vehicles do not go the distance. However, your black Scorpio MH43A5084 is the exception! .

Best regards,

Behram Dhabhar
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Old 18th May 2011, 08:56   #43
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Re: Scorpio Mhawk Clutch Failure & Break Down

Gents, i apologize if i am intruding this thread but I faced a a similar clutch related issue just last night. Just got out of the building and when i pressed the clutch to engage the second gear and clutch just went in and didnt bounce back as usual. The car did get slotted in second gear and was moving. I just pressed the clutch as hard as i could brought it to neutral and safely parked. The clutch pedal for some reason has become totally soft. The clutch pedal is connected with the clutch (slave?) cylinder and there seems to a small pin/bolt assembly which holds them together. Don't know how or when but this pin/bolt assembly had come off. Road assistance didnt have the assembly and the search within the cabin was futile so used couple of inches of hard wire to tie them together. Took the car for a short spin, everything seems to be ok. Couple of Questions
1. Can someone shed more light on this pin/bolt assembly. Is this assembly available separately or will the A.S.S push me to replace the clutch cylinder assembly.
2. What could be the approx expenses for replacing the cylinder assembly. It is a fiesta petrol 1.4.

Appreciate your inputs. Thanks.
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Old 18th May 2011, 09:46   #44
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Re: Scorpio Mhawk Clutch Failure & Break Down

Quote:
Originally Posted by Guderian View Post
......One that has come after going through rough experiences of standing on the shopfloor of the ASCs and getting work done or seeing the vehicle and the work being really buggered up, one that has come from finding the Clutch Slave Cylinder or the Master Cylinder or the various other components give up under your feet after just a few thousand KMs. I am sure one needn't recount all the horror stories one has gone through at the ASC to get the folks there to understand what has gone wrong with the clutch and how and then trying to ensure that a proper work is done !.....
Quote:
Originally Posted by tsk1979 View Post
....Does it crawl through traffic so slow that if you are in first gear idle, you will hit the vehicle in front unless you press the clutch half way.
Or does it travel on uphill roads so bad, that you can't maintain enough speed so as not to stall the vehicle.
These are real world conditions. If your vehicle clutch lasts 350000kms inspite of driving in these conditions daily. hats of to you and your vehicle.
Well said!

@DHABHAR.BEHRAM - Thanks for your detailed replies. Granted that your test vehicles are unbreakable and have a clutch life of 350,000 kms and beyond even in conditions that are more brutal than real world conditions. But, as you have also acknowledged the fact that "customer vehicles do not go the distance", why this mismatch between a test vehicle and a vehicle delivered to a customer? Surely not all of your customers are drivers with bad clutch usage habits? Also, what is M&M doing to address this rather obvious weak area in the Scorpio [particularly the mHawk variant]? Can't speak for others, but this is what I am interested in knowing, rather than the names and acronyms of your tests, how you test, what you test, where you test, how fast you go etc.

Cheers,
Vikram

Last edited by comfortablynumb : 18th May 2011 at 09:48.
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Old 18th May 2011, 10:04   #45
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Re: Scorpio Mhawk Clutch Failure & Break Down

@ Behram Dhabhar - Sir, I appreciate your time and effort in explaining how the cars are tested and how important it is to someone like you to design & engineer a product.

I can relate a lot of things you have mentioned, to my work environment, when my clients complaint about how their network infrastructure does not function and we isolate the root cause. In other words, my client is not bothered, what cables we use or what hardware is used. To him, his business should be up & running.

Similarly, I really don't care, what different parts, when compiled together, makes a car. Since I paid over a million bucks. However, if something does go wrong (in this case the clutch) I would like to know the reason why it failed.

Could you please be kind enough to tell me, who do I send the defective parts to, so someone can tell me that if the part failed, is due to wear & tear or something else caused it to fail.

Regards
Avinash

PS : The car is still at the service center and its been a week. I have not received one call from the A.S.S, updating me on the status. I guess, I'll take this up with the IG Workshop manager and see how it goes.

Last edited by aviorp : 18th May 2011 at 10:07.
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