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Old 12th November 2007, 10:24   #16
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Seems to be a lot of mis-information about on timing chains.

I've seen two engines die. One was my own original-model Honda Civic, relatively low milage, but about 14 years old. Big end seized. Hole in crankcase, lots of smoke, dead engine.

The other was a GF's elderly Nisan Micra. That was the timing chain. Less dramatic, but just as terminal as far as the engine was concerned.

Both of these were petrol cars.

Big ends, timing chains, whatever: these are components that mean huge, quite likely terminal damage to the engine if they fail. You have to accept that such components exist: engines is complex things!

Clutches can vary from car to car in the same model. People say Swift diesel clutch is hard; mine is soft! Some adjustment should be possible.
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Old 12th November 2007, 23:03   #17
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Default diesel dilemma

I seem to have drawn too much flak for my comments against diesel engines. I am sorry if I have hurt the sentiments of diesel car owners but my comments are based on what I am told by several friends and mechs. I do not claim to be a techno wizard in things automotive but my opinions are based on part experience and part hearsay, however right or wrong. And yes, I have never owned a diesel car and I have been severely advised against it by 7 out of ten people including some diesel car owners themselves. May be all you diesel lovers are right but here is what I observed in countless drives in friendsí diesel cars.

The clutch is invariably hard in almost all diesel cars. Noise and vibration is another factor which tires you after a while on a long drive. And yes I have seen some Accent CRDi which shed much of their punch after 60,000 to 70,000 kms on the odo. Fuel pump is an issue too. Then there is the problem of black smoke. One day we couldnít overtake a diesel Innova in our Baleno because it was belching thick black smoke. The smoke was so thick we couldnít see the road ahead. It was like those Bond movie smoke screens to shake the pursuer off oneís tail. The minute Innova dropped a gear and stepped on throttle, it would belch smoke. This isnít an isolated incident. I saw this in many diesels, CRD or non-CRD, and they generally emit smoke around 100-120 kph speed. Also tyre and suspension life is shorter in diesel cars. I am sure this cannot be disputed.

Regarding timing belt snap ups, some times it can snap just before due mileage of replacement. This mechanic swears that if timing belt snaps in a diesel car then it results in engine rebuild and the cost involved is astronomical. He scared me to the point of deciding against buying a diesel car that I had been contemplating for some time now. If all you diesel lovers are right then I was brainwashed by this guy.

One diesel lover commented that countless battered Sumos/ qualises/indicas are proof that diesels are superiors. I am sorry but I do not buy this theory. They may be falling apart and still running but we do not know how many countless trips they have made to the garage and how much money they have spent on these cars. We see many battered Premier Padminis, too, from 50s and 60s. That doesnít mean Padmini is a superior car.
Yes, diesels have their advantages. Apart from the economy ( until something goes wrong, that is ), the biggest advantage is drivability in the city and up to 120 kph. Diesels generally have all the torque piled near idling rpm so they just take off from idling, leaving petrols way behind. Some diesels have their peak torque so near idling speed that you can ignore first gear altogether and drive straight away in second gear. Petrols on the other hand have peak torque near redline so at idling very little torque is available and hence one has to be careful while releasing clutch. Any quick release and the engine stalls. While in diesel you can lift your foot straight off the clutch and the car would pull without stalling. But on the highway, things change. Diesels generally run out of breath and beyond 120 kph the tacho needle shoots up but the speedo does not catch up. On the other hand since petrols have their peak torque near redline, the speedo overtakes tacho beyond 3000-4000 rpm and speed just keeps coming and there seems no stopping. So top end is far better in petrol cars while acceleration up to 100 kph is better in diesels.

]Which is better? I donít know. Every thing has pros and cons. Itís what you want primarily that swings your vote in favour of one or the other. As for me, I may switch to diesel if things improve a little more and if manufacturers stop treating diesel car buyers like suckers--- I mean not providing ABS, airbags and alloys in diesels if they have a petrol version. And yes, if somebody successfully convinces me that if a timing belt snaps in a diesel car, nothing happens and the only thing to be replaced is a timing belt. And yes, if somebody also convinces me that the hard clutch that I feel in a diesel car is not a hard clutch but just a figment of my imagination. Until then, Iíll stick to petrol, thank you. BTW where are all the petrol heads? I have seen none come to my rescue, LOL. Are they also convinced that Iím wrong?

Note from mod: Do not use FONT and SIZE tags

Last edited by tsk1979 : 12th November 2007 at 23:32.
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Old 12th November 2007, 23:14   #18
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OT: @pgsagar, pls do not key in your messages into a word processing appln / mail and then copy-paste into TBHP. This causes font formatting data to be displayed in vain. If you still do, use the 'Remove Text Formatting' link seen just above the message compose /reply box to remove such formatting .

Else, notepad is good.

Last edited by condor : 12th November 2007 at 23:17.
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Old 12th November 2007, 23:36   #19
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pgsagar, with modern diesels the cost of maintenance is only slightly higher. As for timing belts etc., you have been misinformened. Even in a Petrol car(interference engine) timing belt breakage will cause diwal(a)i

There is one place where petrol cars score. If you get really bad fuel in your crdi, you are looking at much more expensive repairs as compared to MPFI. But manufactures are putting in more and more advanced fuel filters to counter that.

In Europe diesel costs slightly more than petrol, but even then they are moving to diesel due to better fuel ecnomy and reliability.
Diesel engines run at lower rpm as compared to comparable petrol cars and wear and tear is less.

Even in Le Mans, which is the ultimate endurance test, the diesel is the king.

What you have been told was true 5 years ago, but today the slightly high maintenance costs are easily offset by the benefits.
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Old 13th November 2007, 00:29   #20
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What's an interference engine?
Is NHC iDSI an interference engine?
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Old 13th November 2007, 01:42   #21
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I agree with tsk that it is not a fair comparision between the old gen diesels with the new gen multijets and vgts.
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Old 13th November 2007, 07:16   #22
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Quote:
Originally Posted by anandpadhye View Post
What's an interference engine?
Is NHC iDSI an interference engine?
An engine is an 'inteference engine' when the piston & valves occupy the same space at different times...ie. the valves move down when the piston is not occupying that space (as in moving downward from TDC) & are in their seats when the piston is at TDC.

All this is highly timed & that is where the timing belt plays such a crucial role.

All modern 4valve/cylinder engines are of the inteference type.

The opposite of interference is freewheeling (in the automotive sense).

Hope this helps.

Last edited by 1self : 13th November 2007 at 07:19.
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Old 13th November 2007, 09:31   #23
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Innova diesels belching smoke?? Thats the first time I have heard this one. Any diesel when lugged emits black smoke. I "BELIEVE" even petrol engines would belch smoke (invisible albeit) when lugged.
As for higher maintenance costs, it all boils down to ROI. Diesels are workhorses and their better efficiencies only work to your advantage

Modern day diesels have definitely narrowed that gap that once existed with petrols vis a vis maintenance costs. I guess only an objective analysis from someone who has (had) both petrols and diesels will guide us better here.Here say and opinions will only confuse everyone more.
If you want to buy a diesel, then read up these forums better and ask around. There are enough junta here to give you good statistical dataset to help make your decision.
As for mileage, I will take your side when it comes to the mindset of the populace (by and large) that buys diesels. come on guys, people buy it only for the mileage.
Swift VDIs owners may be exceptions(and this is a very very recent phenomenon). But majority Indian Junta buy only for diesel mileage and cheaper fuel. Rural india still works only on SUMOs, Indicas, Taveras, Octavias and Qualis. You will find nary an SX4 or an Optra or a pure petrol car that gives mileage in single digits.

Last edited by Venkatesh.C : 13th November 2007 at 09:32.
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Old 13th November 2007, 10:09   #24
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No hurt sentiments, psagar --- just you have been very wrongly informed on several counts, and I feel you would do better to listen to the correspondents on this thread than to your mechanic. I really have to express doubt as to his qualification to be a mechanic.

I was talking with a German taxi driver once. His car is in use 24 hours a day, with one brother working days, another working nights. I was astonished to hear that they expect their engines to last well over the first 99,999 Km around the clock, and, in Germany, no taxi is going to be permitted to belch black smoke. Yes, I'll admit it was Mercedes, but I think it still beats a petrol engine of similar price/quality.
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Old 13th November 2007, 10:44   #25
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my 2 cents
regarding timing belt, i heard that in innova diesel, there is nothing called timing belt, instead they are using a chain. correct me if i am wrong innova owners
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Old 13th November 2007, 11:10   #26
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I don't think it is an issue whether it is a belt or a chain. It needs to be durable, as the consequences of failure are. to say the least. expensive. It needs to give connection with no stretch or give; it needs to be very precise component.

I'm sure that this can be accomplished with a synthetic belt these days. Maybe better? A belt is one moving part; a chain is many.
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Old 13th November 2007, 11:11   #27
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Quote:
Innova diesels belching smoke?? Thats the first time I have heard this one.
The early diesel Innovas had this problem. Search within our forum itself to find the complaints.
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Old 13th November 2007, 12:59   #28
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sagar: You have not hurt sentiments. You expressed an opinion that was more of hearsay than on facts; hence the terse responses. This forum is here to dispel myths & flase theories in the automobile sector.

btw, whoever said that diesels ahve all their torques piled up at idling speed and loose breath after 120 kph. Try a drag with a diesel and you will be surprised. Diesels have a very very long torque unlike their petrol bretheren.

Recently on my trip to Jaipur I was doing 130 kph on NH8 in my Scorpio with the tacho at 2200, when a Skoda 1.9 TDI overtook me. I just floored the pedal and overtook the Skoda at 145 with the tacho reading 3K. And yes, my friend who was following me also in a Scorpio told me that there were no emissions from the tail..

I've seen CRDes not emitting smoke at all even on sudden acceleration. Even otherwise what is a diesel if it doesn't emit a bit of smoke?


Quote:
Originally Posted by pgsagar View Post
I seem to have drawn too much flak for my comments against diesel engines. I am sorry if I have hurt the sentiments of diesel car owners but my comments are based on what I am told by several friends and mechs.

Yes, diesels have their advantages. Apart from the economy ( until something goes wrong, that is ), the biggest advantage is drivability in the city and up to 120 kph. Diesels generally run out of breath and beyond 120 kph the tacho needle shoots up but the speedo does not catch up. On the other hand since petrols have their peak torque near redline, the speedo overtakes tacho beyond 3000-4000 rpm and speed just keeps coming and there seems no stopping. So top end is far better in petrol cars while acceleration up to 100 kph is better in diesels.
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Old 13th November 2007, 13:18   #29
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Quote:
Originally Posted by gd1418 View Post
Recently on my trip to Jaipur I was doing 130 kph on NH8 in my Scorpio with the tacho at 2200, when a Skoda 1.9 TDI overtook me. I just floored the pedal and overtook the Skoda at 145 with the tacho reading 3K. And yes, my friend who was following me also in a Scorpio told me that there were no emissions from the tail..
http://www.team-bhp.com/forum/buckle...ash-style.html

Couldn't help it
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Old 13th November 2007, 13:46   #30
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What I didn't mention that there was a merc that overtook me and also an Elantra. I didn't floor the pedal then.

The Skoda driver was a young boy who after passing me made eye contact on the RVM and thumbed me. It was then that I floored the pedal. Did I tell that he had a PYT as a co-passenger?

Maybe Scoprio/SUV drivers generally are rash coz of the false sense of power that they feel sitting at least 3+ feet above the ground and munching the tar with their 16/17 inchers. But not all of them are so.

I've seen rasher/rowdier drivers in Zens, Swifts, Baleno, VTECs etc., with free flow exhausts and 'dhanchik' ICE making generally a nuisance of themselves on the road & discomforting others.

Quote:
Originally Posted by androdev View Post

Last edited by gd1418 : 13th November 2007 at 13:49.
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