[sridhga]

I want to know how difficult or what are the issues with driving Diesel Naturally Aspirated Indica on Hill roads. Last year I was in Darjeeling and Sikkim and I have not seen any indicas plying there unlike in the other parts of the country. Any views or suggestions for driving Indica on the Hills?

[rkbharat]

First thing, no issues at all on driving Indica on hills. Just get the air filter cleaned, get all electricals checked, and get it serviced, thats all.

If its old gen Indica, you might feel very minor jerks on high altitudes, but nothing beyond that.

I had 2002 Mar DLS model, driven all over Himachal and Uttaranchal without a single problem.

[nishantgandhi]

Originally Posted by rkbharat

First thing, no issues at all on driving Indica on hills. Just get the air filter cleaned, get all electricals checked, and get it serviced, thats all.

If its old gen Indica, you might feel very minor jerks on high altitudes, but nothing beyond that.

I had 2002 Mar DLS model, driven all over Himachal and Uttaranchal without a single problem.

Same here. I had 2002 April V2 DLS and drove it all the way to Nainital and Corbett. No issues what so ever.

[tsk1979]

Nainital etc., are not high altitude. When you hit above 3000mts above sea level, any normally aspirated diesel car will have some missing and black smoke.
Cars with ECU and electronic fuel pump do slightly better, but there is no substitute for oxygen.
Turbo charged cars which have forced induction, do better at high altitudes.
With a poorly cariberated fuel pump(eg if you are already running rich), even at 2000mts above MSL you may encounter occasional missing.
Even a clogged air filter can do the same thing as engine starves of oxygen.

[headers]

Originally Posted by tsk1979

Nainital etc., are not high altitude. When you hit above 3000mts above sea level, any normally aspirated diesel car will have some missing and black smoke.
Cars with ECU and electronic fuel pump do slightly better, but there is no substitute for oxygen.
Turbo charged cars which have forced induction, do better at high altitudes.
With a poorly cariberated fuel pump(eg if you are already running rich), even at 2000mts above MSL you may encounter occasional missing.
Even a clogged air filter can do the same thing as engine starves of oxygen.

One can fill up on the high altitude petrol stations. They usually have additives added in the fuel to overcome this problem.

I've had the exact problem what tsk mentioned in 2004 while going from Chennai to Ooty. Made the misake of filling up in Coimbatore and the car struggled to climb the ooty ghats.

Went to a nearby Tata Service - Removed 25 litres odd diesel and gifted to them and filled up from a nearby fuel station with the additives, the problem dissappeared after that - I was and am a regular user of SYSTEM D in all my diesel cars. Inspite of the System D - the fuel at the plains do not have the same content of the fuel at the hills.

Same applies to kodai too.

This is really a funny problem.

[dadu]

I dont think the winter fuels supplied at these locations have anything else apart from anti-freeze and thinning agents to survive the cold there. Even these are required only if the temp goes below -15.

This could just be a case of adulterated fuel at Coimbatore.

Originally Posted by headers

One can fill up on the high altitude petrol stations. They usually have additives added in the fuel to overcome this problem.

I've had the exact problem what tsk mentioned in 2004 while going from Chennai to Ooty. Made the misake of filling up in Coimbatore and the car struggled to climb the ooty ghats.

Went to a nearby Tata Service - Removed 25 litres odd diesel and gifted to them and filled up from a nearby fuel station with the additives, the problem dissappeared after that - I was and am a regular user of SYSTEM D in all my diesel cars. Inspite of the System D - the fuel at the plains do not have the same content of the fuel at the hills.

Same applies to kodai too.

This is really a funny problem.

[headers]

Originally Posted by dadu

I dont think the winter fuels supplied at these locations have anything else apart from anti-freeze and thinning agents to survive the cold there. Even these are required only if the temp goes below -15.

This could just be a case of adulterated fuel at Coimbatore.

No Dadu, I guess not, It is one of the most reputed bunks in coimbatore! The fuel in the hill stations are slightly different. They compensate for the lack of air / oxygen and make your car perform.

[sudev]

Hhmmm first time I am hearing this about special fuel for hills.
Been to ...let me count 1.2.3.4.5 raids... all the way to Leh/ and back but no special fuel is available outside of army. Leave engine on or run it five minutes (or more) every half an hour (or more) when temperatures are LOW is how everyone survives if they have diesel. Else hell freezes over. Been there and done that before I learned the remedy. Okay the fuel which army gets is almost as clear as water - more refined? - and technically has anti-freeze and less wax.
So probably the bunk or a bad batch of fuel.

[tsk1979]

My hill trips involve large distances, so I often fill up multiple times at high altitudes.
Its anti-freeze diesel up there, but only in winters.

Inspite of that, above 3000mts there is some missing.
So whether i fill from plains or hill, till about 3000mts there is absolutely no issue.

Even when I went to ooty in the indica, there was absolutely no missing, and fuel had been topped up at the plains. After one day I filled up "Anti freeze diesel" at ooty, and there was no change.
I really wonder why do you need anti-freeze diesel at ooty!
At Narkanda I can understand, but ooty!?

[dadu]

In todays diesel engine the lack of oxygen is compensated by supplying more air to the engine whcih is measured by the Oxygen sensor in the manifold.

The properties are changed for diesel supplied at high altitudes/ cold areas which is to reduce the formation of wax and keep it from freezing both of which can clog the filter and the fuel lines/pump etc. This is for temp below -15 and I am not guessing this.

BP adjusts certain properties of diesel fuel to counter problems that can occur with diesel when the ambient temperatures are cold.

This is because waxes that naturally occur in the fuel can at times solidify blocking fuel filters and result in operational problems. Because this is adjusted seasonally and even by area all you need to do is fill up with diesel from within the area you are operating in.

Originally Posted by headers

No Dadu, I guess not, It is one of the most reputed bunks in coimbatore! The fuel in the hill stations are slightly different. They compensate for the lack of air / oxygen and make your car perform.

[zenx]

Went all over Uttaranchal in an old Indica V2 - there were 3 adults, 2 kids and lotsa luggage at the back. did quite ok - right upto Auli.

[headers]

Originally Posted by dadu

In todays diesel engine the lack of oxygen is compensated by supplying more air to the engine whcih is measured by the Oxygen sensor in the manifold.

The properties are changed for diesel supplied at high altitudes/ cold areas which is to reduce the formation of wax and keep it from freezing both of which can clog the filter and the fuel lines/pump etc. This is for temp below -15 and I am not guessing this.

Dadu, I agree 100% on this.

The Indica 02 DLX I had, had no O2 sensor and ECM. Hence when it came to cooler climate and with not so good diesel, the car laboured in pain. The Tata guys initially wanted me to re-calibrate the fuel pump in my car which I strongly objected to. As an alternative, we did the change of fuel thing!

The amazing thing is that until that point in time, I never realised that diesel cars labour when it comes to a slightly rarer environment.

[anupmathur]

Originally Posted by headers

The amazing thing is that until that point in time, I never realised that diesel cars labour when it comes to a slightly rarer environment.

LOL Headers, if you'd grown up in these northern cities where we head off to the hills every summer, you'd have childhood memories of BLACK smoke gloriously shooting out of the tailpipes of ALL trucks and busses in the mountains! Those were the only diesels around back then.
Petrol engined vehicles were invariably 'clean'.

[DirtyDan]

Originally Posted by dadu

I dont think the winter fuels supplied at these locations have anything else apart from anti-freeze and thinning agents to survive the cold there. Even these are required only if the temp goes below -15.

This could just be a case of adulterated fuel at Coimbatore.

Dadu, my understanding, which is from North America and not India, is that diesel fuel will start to gel around -6.7 degrees celsius. The fuel may get thick enough to clog a fuel filter at that point and stop the motor. This is called the "Cloud" point as the diesel fuel gets cloudy in appearance at this temp as paraffin in the fuel starts to crystalize. The "pour" point, the point at which the fuel totally gels up and will not pour from a container is around -11 to -15 degrees celsius. In North America, all the way to frozen Alaska, diesels run in the winter just fine with additives down to -45c. Then, you have other problems, gear oil starts gelling up, your tires no longer flex easily, your coolant may freeze solid...stuff like that. They overcome this by using heaters on motor blocks, oil sumps, fuel tanks, fuel lines and batteries. These plug into normal electric outlets and are often used overnight only to assist cold starts in the morning. Occassionally, work places also provide electrical outlets for heating vehicles. This is only in the far north, the Dakotas, Minnesota, Alaska. It is not needed in most places in N. America. Certainly not India unless you are wintering in Leh, Ladakh or someplace and time like that.

Other than a slight concern with fuel, there is no reason I can think not to run a diesel in most places. They are great at running up hills, lots of torque. My personal experience is that you may get some loss of power starting at 3000 meters but I ran my Tata Spacio 3.0L diesel around Leh and over the Khardung La at 5578 meters with no trouble save a small but noticable loss of power only when I really put my foot in it (full throttle) and there was rarely a need for that.

[gd1418]

How can fuel compensate for lack of air/oxygen? It doesn't make sense. Fuels available at bunks at high altitude places are a bit dark in colour and are mixed with anti-freeze so that when the vehicle is stopped for some hours or overnight at high altitude, the fuel in tank and fuel lines doesn't get frozen, thus assisting in starting the engine.

Originally Posted by headers

No Dadu, I guess not, It is one of the most reputed bunks in coimbatore! The fuel in the hill stations are slightly different. They compensate for the lack of air / oxygen and make your car perform.