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Old 8th March 2009, 19:17   #31
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Originally Posted by anupmathur View Post
...what you consider acceptable...Most diesel engined vehicles have a vibration issue somewhere in their rev band....
Hi Anup, I competely agree with everything stated by you. Keeping in mind your post however, its the "vibration issue somewhere in their rev band" that I am raising an "objection' to. The problem is that the rev band is 1200 to 1400 which is a band that is very commonly used, not only in accelaration / deccel but also in constant speeds. Its a band that is extremely hard to avoid, which if you try to, you end up revving hard or lugging as the case may be.

I wonder how that got past the R&D, or maybe it as something that develops in 'used' engines, at a later point in their life? Also another thought was that this could be the exhaust system (tail pipe and box) that may be setting up a harmonic?

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Originally Posted by raj_5004 View Post
& mohnish: is you other car a petrol?
as anup sir said, you should expect some amount of vibration in a mahindra diesel! but to be frank, the scorpio CRDe engine is very refined & smooth, so i feel you will have to adjust with that.
Yes Raj, I agree, the Crde is refined ( but I have the non ). Infact I personally find all the Scorpio (nons and Crdes) pretty darn good vehicles. I think all Scorpio owners do.

To answer your query, I have petrol as well as diesels, and am not comparing the two in any way whatsoever. I am actually raising a doubt on the fact that there is a mild but noticeable vibration in a particular rpm band only in an other wise completely smooth engine. Had this vibration been throughout, i probably would have ignored it and attributed it to inherent engine vibration. But when the enigne can be so so smooth through and only 'misbehave' at a particular rpm (that too a very usable rpm) I start raising questions and try to solve the thing.
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Old 8th March 2009, 19:55   #32
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Originally Posted by Mohnish View Post
The problem is that the rev band is 1200 to 1400 which is a band that is very commonly used, not only in accelaration / deccel but also in constant speeds. Its a band that is extremely hard to avoid, which if you try to, you end up revving hard or lugging as the case may be.
Mohnish, I personally find this rev band to be a tad lower than where I tend to operate. This is the point where the turbo boost is just about becoming available. The fun starts above 1600 rpm!
Isn't it the same for the non-CRDe Scorpios?

You are right in saying this band is very hard to avoid. I'd say it is well nigh impossible to avoid! You need to get past this to unleash the real responsiveness of the engine! That's how it is for the CRDe.

Also, with age, vibrations will increase, on account of the engine mounts losing some resilience. I'm sure changing those would help in any car with Indian genes. Our rubber parts do not endure too well.
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Old 8th March 2009, 20:11   #33
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Originally Posted by anupmathur View Post
Mohnish, I personally find this rev band to be a tad lower than where I tend to operate. This is the point where the turbo boost is just about becoming available. The fun starts above 1600 rpm!Isn't it the same for the non-CRDe Scorpios?
Yep agree about the "fun starting" !!! but again i feel without reason, unneccessarily revving the engine at 2200 rpm (in 2nd) when you can move along at the same speed at 1400 rpm (in 3rd) in traffic is a waste (fuel / engine life). Hence my reasoning, and also the fact that why should I have to adapt my driving style to a more 'aggressive' posture just to accomodate an engine querk?

about the turbo in the non Crdes, I 'feel' it whirl and swoosh around 2000 rpm.
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Originally Posted by anupmathur View Post
You are right in saying this band is very hard to avoid....
Do me a favour...Next time you 'saddle up' !!! check out if you find there is any kind of 'increase' in your Crde engine vibration threshold between 1200 to 1400.
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Originally Posted by anupmathur View Post
...I'm sure changing those would help in any car with Indian genes...
Have already change the engine / gear mounts and it did make a difference (refer my first post #23 on this above). Regards the Indian genes...though the wearable parts do wear out earlier than our imported counterparts, I still change these parts on a 'fairly' (depending on cost factors and ease of job etc.) regularly on my Benz too.

Do check your Crde between 1200 and 1400 and post...Looking forward to your findings.

Last edited by Mohnish : 8th March 2009 at 20:12.
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Old 9th March 2009, 01:39   #34
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I must say you have excellent observation. My Scorpio is CRDe type, driving mostly in city for last two years.
Do you find these vibrations always ? Or sometime someday it is there and and sometime it is not ?
There are some known problems with Scorpio, atleast the one I have, is very sensitive to tyre pressure. If tyre pressure is less, vehicles handling, vibrations everything changes.
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Old 9th March 2009, 09:58   #35
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Default Thread TITLE!!

Dear Moderator,

Request you to rename this thread as "SCORPIO-ISSUES & SOLUTIONS".

This will cover all models of scorpios and would help us to continue our discussion without having posts deleted.

Thank you in advance!!
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Old 9th March 2009, 10:33   #36
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Originally Posted by a_mukherji View Post
...Do you find these vibrations always...
Its engine running related (which could be power steering pump/exhaust system/alternator/ac comp etc...) and always present, under all conditions. However, in my search for the sorce, I disconnected the fan belt thereby negating the effect of the engine strap ons (power steering pump etc..), but the vibration still exists. Leqading me to believe this is inherent in the engine or is the exhaust system setting up a harmonic vibration.
Quote:
Originally Posted by a_mukherji View Post
There are some known problems with Scorpio, atleast the one I have, is very sensitive to tyre pressure. If tyre pressure is less, vehicles handling, vibrations everything changes.
Agreed, but tyre pressure would have nothing to do with an engine vibration when raising the engine at stand still.

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...Request you to rename this thread as "SCORPIO-ISSUES & SOLUTIONS"...
Yes please rename the thread....Thanks.
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Old 9th March 2009, 13:23   #37
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Originally Posted by Mohnish View Post
Yep agree ........

about the turbo in the non Crdes, I 'feel' it whirl and swoosh around 2000 rpm.

Do me a favour..............Looking forward to your findings.
The CRDe has a Hard Turbo, its on ALL THE TIME, from the time you start the engine, so vibrations would not be due to the turbo kicking in.

I think that stands good for non-CRDe also.

-Ramky
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Old 9th March 2009, 13:49   #38
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Originally Posted by ramkya1 View Post
The CRDe has a Hard Turbo, its on ALL THE TIME, from the time you start the engine, so vibrations would not be due to the turbo kicking in.

I think that stands good for non-CRDe also.
You're right, Ramky, but the turbo could also have vibration issues through its rev-band!

And AFAIK, there is no 'soft' turbo that turns on at a time other than at startup.
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Old 9th March 2009, 14:33   #39
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Originally Posted by anupmathur View Post
You're right, Ramky, but the turbo could also have vibration issues through its rev-band!

And AFAIK, there is no 'soft' turbo that turns on at a time other than at startup.
Yeah Anup, agree with that ... the turbo spins all the time, it builds up boost only after a 'certain' rpm ( boost on smaller turbo at lower rpm / larger turbo later rpm) thats why some engines have a twin turbo, to get constant boost throughout the rpm range.

I doubt the vibration is turbo related...can't explain my statement, its just that it 'feels' more like (now that I have negated all the engine strap ons) a muffler box harmonic travelling through the chassis.

Btw, have any of you'll checked if you get the 'slight' vibration 1200 through 1400? Would really like to know. Its felt more in the steering wheel and the seat, when driving. Sitting in any passenger seat you don't feel it at all.

Last edited by Mohnish : 9th March 2009 at 14:38.
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Old 9th March 2009, 14:45   #40
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Originally Posted by Mohnish View Post
Btw, have any of you'll checked if you get the 'slight' vibration 1200 through 1400? Would really like to know. Its felt more in the steering wheel and the seat, when driving.
Mohnish, I haven't checked so far.
The next time I drive my Scorpio, I'll certainly concentrate on this and post a report here.

Could be a few days, LOL. What better can you expect from one who has done 18.7 k kms in 31 months of ownership?!
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Old 9th March 2009, 15:42   #41
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Originally Posted by anupmathur View Post
You're right, Ramky, but the turbo could also have vibration issues through its rev-band!

And AFAIK, there is no 'soft' turbo that turns on at a time other than at startup.
My hands on (meaning driving a car with turbo fitted in it )experience with turbo is only after 2007, june, before that lots of reading on the subject.

I had to discuss the turbo with ASC Service supervisors(I spent time with 2 of them , one a lady, with great clarity on engine basics, later I read up on the subject thro the web) as I also had vibration issues in the rpm band, 1100 to 1400. They assured me its normal, tested it out on a couple of vehicles there; sure enough they all have a small vibration on some BANDS. If I compare the present vibration to the petrol cars I owned earlier, its pronounced, but compared to my Metador / BMC Ambys I used it have back in the 70's; Scorp CRDe is like velvet.

The ASC average of opening up a turbo to repair it is from 75 kkm to 1 lakh, unless its abused; the one on the Scorp is pretty tough, the bearing related/ vibration related repair of a scorp turbo is RARE and hence my assumption that its not turbo related. YES, it could have minor issues through any BAND, mounting related or harmonics through some connected parts.

As for the HARD TURBO, I don't know why, the ASC guys/gal call it so; know of a cousin's Honda Civic in US had a RevHard Turbos (brand name?). Would be interesting to learn why they call it Hard and not soft

I've heard of people saying / posting "my turbo COMES ON at so and so rpm" as if GOD switches in on, LOL!!!!!
--

Last edited by ramkya1 : 9th March 2009 at 15:44.
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Old 9th March 2009, 16:57   #42
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Originally Posted by ramkya1 View Post
...as I also had vibration issues in the rpm band, 1100 to 1400. They assured me its normal, tested it out on a couple of vehicles there; sure enough they all have a small vibration on some BANDS...
Hey thanks Ramkya...finally someone else has stumbled upon the same findings as me...Same results with me at the ASC in Mumbai.
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Originally Posted by ramkya1 View Post
I've heard of people saying / posting "my turbo COMES ON at so and so rpm" as if GOD switches in on, LOL!!!!!--
I figure it means thats when the turbo 'spins' fast enough to generate boost pressure which is higher than the naturally aspirated suction of the engine. High enough that you feel the 'surge' when driving.
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Old 10th March 2009, 09:55   #43
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Hello Guys,
i drive around 60-70 kms daily in my scorpio & that is over some bad roads. also, while at low speeds i do care to avoid potholes & rough patches but at high speeds, i simply cannot brake because of a speeding car behind me. secondly, my driver is a roughie. potholes & rough roads are non existent for him. he does not take the pain to slow down in such conditions.

as a result, the scorpio's driver door has started squeaking slightly (not rattling) over rough roads. i got it rectified when i went to the A.S.S. for its 15,000 service but now after 200 kms, it re-surfaced. along with that, the middle row seaback used to rattle too. even that is back now!

even though this is not a serious issue, i just wanted to clarify that is anybody else facing the same problem in their scorpios?
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Old 10th March 2009, 10:40   #44
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Originally Posted by raj_5004 View Post
...my driver is a roughie. potholes & rough roads are non existent for him. he does not take the pain to slow down in such conditions...
If you really care for your Scorp,or any other car, then change the driver/teach him to drive/drive yourself...
Quote:
Originally Posted by raj_5004 View Post
...even though this is not a serious issue...
It will end up as a serious issue...Eventually suspension will need work, body rattles etc etc. I hate it when my car looks/sounds uncared for (I am sure you do to.) My take is : a well maintained cared for 'cheap' old vehicle is more impressive than a really expensive import thats treated badly. Respect your car and you win my respect. Respect it so much that it shows...
Quote:
Originally Posted by raj_5004 View Post
...i just wanted to clarify that is anybody else facing the same problem in their scorpios?
I figure Raj, anyone driving rough will end up with these issues.

Friendly advice: Raj, you have beautiful VLX...Take care of it...

May be I am fanatical... or
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Old 10th March 2009, 12:29   #45
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Default Engine vibration 1200 to 1400...research continues!!!

@anup
@ramkya

Both of you'll got me thinking...what if it is the turbo, mabye mounting related as ramkya said or vib in particular rev band of the turbo as anup said....

So, is there any way to "disconnect" the turbo from spinning...A simple way?
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