Preamble
Nowadays, almost all BS-II/III diesel vehicles are fitted with ‘Turbo-Chargers’. These come in different configurations, depending upon the design philosophy of the vehicle manufacturers. So let’s see what’s this Turbo-Charging all about……

Some Basics

1) In Turbo Charging, the exhaust energy of the flow-out gases is used to drive a small Turbine, to which is directly coupled a small Turbine type compressor. The output of this compressor is linked to the ‘Inlet Manifold’ of the Engine.

2) Such TC’s can easily be made to spin at speeds > 100,000 rpm - which enables their size to be compacted because for a given output, the device diameter is inversely proportional to its rpm.

3) When air is so compressed - especially in a TC where the adjoining Turbine section runs @ +500*C or so - being the exhaust gases temp. - the air delivered by it too comes out much hotter - say > 60*C.

4) Since an Internal Combustion Engine actually looks for the suitable ‘weight’ of Oxygen required to burn a matching weight of fuel, rather than temperature dependent volume, it’s desirable to limit its inlet air temps to ~ 30*C or so - for it to deliver its best thermal efficiency.

5) Therefore, to lower the TC delivered air Temp from ~ 60*C+ to ~ 30*C, it has to be cooled by passing it through a suitable ‘Radiator’ - just like the Engine Coolant System. Such an ‘Air-Cooling Radiator’ is called an ‘Inter-Cooler’, coz it’s an ‘intermediary’ between a TC and the Engine.

6) A well designed Turbo Charger/Inter-Cooler System can enable a Naturally Aspirated Engine of the same ‘cc’ deliver easily upto +30% Additional Power - PROVIDED the internals of it are suitably designed also, to handle such levels of power delivery. DIY enthusiasts trying to TC an existing/NA diesel would do well to keep the following in mind :

i) Get its ’static’ compression ratio down to 16-17:1 a/a normal 0f 22+:1.

ii) Also ensure that its vital internals like Crank/Bearings/Conrods/Clutch etc can withstand the additional 30% or so power over its ‘NA’ rating that TC will bring about.

All this/aforesaid is easier said than done, at least as a retrofit.

Some relevant QnA’s

Q1: I was wanting to know when does the turbo come on in the Verna, I mean at what rpm…they say its variable geometry turbo but I’m unsure when it comes on.
A1: Being a ‘VGT’, theoretically speaking the TC ‘cuts-in’ from idling speed upwards itself, like an ‘Alternator’ vis-à-vis ‘Dynamo’s of yore, but obviously not in full strength. The degree of boost keeps building up progressively upto the designed limit - usually + 5 psi over atmosphere. Most TC’s reach this level around 1750 rpm.

Q2: As per OHB instructions, when you stop the vehicle, they recommend a 1-minute ‘cooling off’ time for the TC and not sure whether in routine city use the TC comes in!!!
A2: Your understanding of it is not right. The 1-min wait is recommended for the TC to rev down ’safely’ from its normal 50,000 rpm+ to about 5 k-rpm or so at idling and not to cool down, without losing the pressurised engine oil lubrication system of which it’s an integral part. If one were to switch off the engine immediately after coming to a stop for good, as we do for petrol’s w/o TC’s, then there’s a good possibility that the TC bearings may seize. Likewise at start-up/take off, as is recommended for the rest of the engine, for oil circulation to set in fully incl the TC, as it stands to rev up to 50k rpm from ~ 5k rpm in no time.

Q3: Only if I rev hard do I feel a jolt sort of acceleration at times so how am I sure that when the car is going to halt and I kill the engine whether the TC was in use!!! Is there a way of finding it out.
A3: I think this is now covered in the above 2-explanations ?

Q4: I don’t know if i should worry so much on this!
A4: Just pause for ~30-60 secs after firing the engine first thing in the morning before taking off, and that too gently as always. Likewise when you’ve to switch off the engine for good. Diesels all over the world are kept on idle most times, incl traffic lights/jams, may be for this reason alone - not to mention sub-zero temps that turn diesel fuel into a jelly of sorts. For such s/z duties, diesel fuel tanks of heavy commercial vehicles have electric heaters in their fuel tanks, which have to be switched off before refuelling.

Preamble
My earlier submission on how to take off on a gradient evoked some interesting responses, from friends and ex-colleagues to whom I’d sent its URL from the e-HT. Here’s another one such set of exchanges…

Response #1
SKG, Driving and CEO’s need not at all be compatible! The only driving the CEO’s need to do is to drive their employees round the bend!! I know many CEO’s who have two drivers per car - one from 12 noon to 12 midnight and the other from 12 midnight to 12 noon. There is no knowing when the CEO has to rush out somewhere, e.g. to the airport to catch a plane to New York at two hours’ notice. His driving ability will not do him a fat lot of good under such circumstances - he is probably better off learning flying!! – Jeh.

My reaction
Jeh - thanks for the reaction. I guess it just depends on the context of a country one is talking about. Lemme elaborate…

Some years ago, mid-’80s to be precise, I took upon myself the task of teaching my 2-teenage daughters as to how to drive correctly, for what they’d learn off a local driving school with a permanent driving licence to boot was any thing but appalling.

In the process, I ended up writing a book of sorts, titled ‘Around the World in 80-days without a Flat Tyre’ (free e-copies of its draft available on request). The whole idea was to teach the girls how to take the bull by the horns, without getting hurt or hurting others in the process. They were made to read the proof of it independently, ostensibly to correct howlers but with an ultimate intention of getting some funda’s of a car into their heads.

Little wonder then, that the so called ‘book’ remains in a draft form till date, tho’ both manage to drive reasonably well 20+ years later/today - with some crashes in their respective driving cv’s. Its opening line of the chapter on ‘driving correctly’ goes like this…

“Prof. Peter Drucker is reported to have once remarked to a distinguished gathering of Business Managers from all over the world, that give me a ride in your car with yourself at the wheel and I will tell you what kind of a Manager you are”.

This statement to me conveys a lot of meaning. As on closer introspection, the way you drive and maintain your car, no matter whether provided by the employers or funded out of your own resources, speaks volumes of your attitude towards life in general and your managerial skills in particular. After all, a car responds to your commands, your road side manners and their consequences, whether pleasurable or otherwise, are entirely of your own making.

How well you maintain it to give you a reliable and uninterrupted service also indicates how well you run your business, by way of preventive measures to forestall unpleasant situations. Before one can effectively maintain and satisfactorily drive a car without inconveniencing oneself and others around him, it is but natural that one understands how exactly a car works - like trying to understand the intricacies of your business which you are expected to steer to satisfaction.

So, where does that leave us Jeh?! Money or corporate perks may be able to get you double shift drivers but not much above the ground in dear Peter’s esteem!

Counter reaction
Good point SKG, noted. Jeh.

Response #2
Bahut sahi darshaya hai aapne. In fact in Mumbai when I gave my driving test [having driven our Ambi exactly for 4 days prior to the test] the guy asked me to take off on a slope after a stop and had to do the same stuff without a handbrake as the Ambi’s hardly had any…. to boot ours had a slipping clutch too but I managed quite well. The guy finally asked me how long I had been driving as my temp license was only 3-mths old. He would not believe that it was only a week since I had started! In hindsight, I should not have mentioned the 1-week bit. But still 99% of the guys cannot take off smoothly on a slope even if they use the HB, and most times they are in the wrong gear as well – Cyrus.M.

My reaction
As far as driving goes Cyrus, it’s well said that either you have it in you or you don’t. I’ve seen highly successful Co. Directors/CEO’s making a complete Ass of themselves under such conditions :-0)

Counter reaction
With due respect to all the CEO’s SKG, I still stand by Prof. Drucker’s logic. I have applied it myself on some of my colleagues without letting them know of my intent and every time it comes up trumps. Cheers Cyrus.

Stafford, England, July 1959.

Sunny day. My mood very good after a hearty breakfast but just to spoil my sense of all well being, Dilip rushes into my room cursing ‘that SOB’, and headed straight for a beer. I said nothing, knowing Dilip wasn’t one to keep quiet for long.

Sure enough, after a few sips of beer Dilip said, “You know - that damned Jennings failed me again in my driving test today and that too for a stupid reason. He has done this to me for the third time!”

I felt sorry for Dilip but knew he must have done something wrong from Jennings’ viewpoint and retorted “Tough luck, Dilip. Not for the same reason as on previous occasions, I guess?”

“No, first time he failed me because when he asked me to reverse the car, the road was narrow and I had to maneuver it back and forth and in that process I hit the kerb stones a few times. He had also asked me to stop at some point and I pulled up without caring for the NO PARKING sign at that point. So he found fault with me for that too. He said I should not have obeyed his foolish instructions!

The next time he asked me to reverse into a lane which we were just passing and when I did so, he found fault with me for not looking left into the lane as I passed it to make sure there was no vehicle parked at the entrance to the lane or if any car was coming down the lane.

Today he asked me to stop the car on a road with steep gradient and then asked me to get going again. He failed me this time because I rolled back a little bit, just a foot or two, before moving forward. I am actually beginning to think that Jennings is racist and that is why he is harassing me”.

“Was that the only reason for him to fail you this time?”

Dilip thought for a while and said “Well, no. Jennings was also not happy with my passing a zebra crossing when there was a pedestrian standing on the sidewalk, waiting to cross the road. He said the pedestrian always has a right of way at zebra crossings and even if he hadn’t actually stepped on to the zebra patch, I should have respected his right and stopped the car till he crossed the road. How silly!”

I did not agree with Dilip at all, but got worried a bit about Dilip’ s failure because I was myself due to take a test the following month. Anyway, I tried to comfort Dilip by telling him that I know of people who have cleared driving tests in their 4th, 5th or even 6th attempt and he may not be fair in accusing Jennings of racism. Don’t you know that Mr. Sen got through last month in only his second attempt?”

Stafford, August 1959, The Big Day.

Contrary to my fears, I cleared my test today in the first attempt. I did not commit any of the mistakes that Dilip did (am I grateful to him for forewarning me!). But Mr. Jennings did cause some worry by repeatedly accusing me of being hard of hearing, when I did not heed a police message, which he said was clearly audible.

The police that day were piloting a 24-double wheel low bed trailer truck carrying a massive transformer and hailing all traffic to get on to the foot path to allow the truck to pass. I did so only belatedly, perhaps after the third message.

I countered Mr. Jennings’ accusation by telling him bluntly that I was not deaf, but certainly nervous and that he too may have acted the way I did if the roles had been reversed. He had merely grunted then, and I thought I had cooked my goose. So it was a pleasant surprise to me when, at the end of the test, he pulled out a pre-printed pink slip from his pocket, signed it and gave it to me saying “You can pick up your licence on Wednesday next”.

I asked him incredulously, “Are you passing me, then?” He looked at me grimly and said, with typical British seriousness, “If you are unhappy, I can fail you even now, you know”. Suddenly he flashed a bright smile, thrust the slip in my hands, and said “Good luck with your driving! Be a careful and considerate driver always” and walked off. Whew! To think I was only the second Indian in Stafford in several years to clear the driving test in the first attempt, after my senior colleague Mr. Natarajan who made it in 1957!

47 years on, Bangalore, November, 2006

Returning home from a wedding and had just turned into Queens Road from M G Road after the cop had waved me on. Suddenly a big thud and my windscreen broke into a million pieces and an old man, his wife, grandchild and a scooter, all lay sprawled on the road.

Fortunately no serious injury to any of them, though a crowd soon gathered around us as is usual and a roughneck from among them demanded that I summon an ambulance, take the two-wheeler-riding-family to a hospital and pick up the tab for their medical treatment.

My protests fell on deaf ears, but fortunately the cop who was witness to the accident intervened and proclaimed that I was not at fault because the old man had jumped the signal. The crowd melted away, but much to my chagrin, I discovered the old man had no driving licence, nor did the scooter have any papers!

For some strange reason, I remembered Dilip and Jennings then and thought to myself “Mr. Jennings, you took so much care to ensure Dilip became a safe driver; where are the ‘Jennings’s’ who will put people like this old man to the grind that Dilip went through?”

Post Script:

Dilip got his licence on his fourth attempt, continued to drive badly (without accidents, though) until he died some 8 years ago. Innumerable have been the times that I lamented the rotten standards of our driving schools, the incompetent RTOs who dish out licences freely to people who are willing to bribe their way, the apathy of the people and the police alike in bringing about disciplined driving. As for me, I ‘forgave’ the old man (who seemed to be penurious) to avoid police formalities and was poorer by some 16 K, the depreciation amount disallowed by the Insurance company.

Oh, Mr. Jennings, why didn’t you check me out also to see if I could dodge the road mongers of Bangalore?!

Preamble
When it comes to reversing and taking off smoothly on an up-gradient, most drivers in our country no matter how ‘experienced’ are quite at sea. The reasons for this are not far to fathom as unlike in the West, there’re hardly any well-organised driver training programs in the country. In fact, things are so bad in some of the states that depending upon one’s clout, one can get a driving licence delivered to one’s door-step - w/o even having to fill-up a form!

The solution to such a problem that most people face can best be ‘demonstrated’ live by a ‘good’ driver, rather than instructions on a printed handout. None the less, let me try…

1. Using the Hand Brake to ‘assist’ is the right thing to do. In fact out there in the West, it’s mandatory to shift the Car to neutral and engage the Handbrake when coming to a stop, such as on traffic lights. The reason being - i) you don’t roll forward/backward unknowingly and ‘kiss’ the guy ahead/behind you, and ii) if some one hits you from behind, you don’t take-off and start a chain reaction.
2. Likewise when you have to stop on a slope, engage the HB fully first and then shift to neutral and take your foot off the clutch. This presumes that your hand brake is correctly adjusted and in good working order to hold the car there, without having to reinforce it by shifting into 1st or Rev. gear.
3. Now comes the tricky part - to take off smoothly on an up-gradient w/o the engine stalling or the Car rolling back. In fact it’s as easy as learning to ride a bicycle, once you get the ‘hang’ of it. Here’s what you do -
   • With the HB still fully engaged you start the car, get into the first gear, rev-up the engine somewhat above the usual and only then let the clutch go slowly - till the Car ‘attempts’ to move even with the HB engaged - which will be apparent by the engine tending to stall and thus demanding more accelerator.
   • NOW you ‘co-ordinate’ the clutch release + more accelerator AND ‘progressive’ handbrake release in such a manner that the Car smoothly moves fwd w/o stalling or rolling back. It’s a skill easily acquired by getting the ‘feel’ of things and not getting nervous about it.
4. Always remember that it’s you who’s driving the Car and not the other way around. It’ll do exactly what you command it to do - knowingly or unknowingly.

Driving with Hand Brake ON
This is another area that afflicts most drivers at some time or the other, tho’ a sensitive driver should be able to detect it sooner than later due to the ‘drag’ it’ll create. Notwithstanding, depending on the extent of its engagement and the speed/distance covered, the damage to the rear wheel/drums ‘Assembly’ - where alone the handbrakes work - can be from insignificant to considerable.

Such damage will arise due to very high localised temperatures within the drums as can be imagined - leading to:

1. Permanent Damage to the brake shoes - calling for their replacement.
2. Likewise to the Hydraulic Wheel Brake Cylinders and
3. The Wheel Bearings.

If one doesn’t feel any adverse effects soon after having driven some appreciable distance with the HB ‘on’, it’s recommended that one gets the rear drums opened at the next service and has all the above three properly inspected, tested and replaced as necessary.

If the (2) above appear undamaged, they must atleast be completely ‘bled’ to drive-out the boiled over/deteriorated Brake fluid that would be trapped in them and thus hampering their proper working.

Preamble
Many people, mostly youngsters with their fathers’ deep pockets, often ask me how to soup-up their cars - more to show off and impress the girls at large rather than participate in an amateur Rally.

There are several aspects and consequences to this - topmost being annulment of one’s OE Warranty if in force and even if not, invalidation of the Insurance cover for having carried out ‘un-authorised modifications’. In other words, if one were to be involved in an accident resulting in substantial 3rd party claims, such as a loss of life, you’ll be on your own w/o any Insurance!

So let’s have a look at some of the common options available:

A - The Simplest and the Cheapest
For an average motoring enthusiast who is not interested in ‘drag-racing’ kind of events, replacement of ’stock/paper’ Air Filters with ‘K&N Free-Flow’ type is the most cost effective bet.

These basically come in 2-varieties - one which is a straight replacement of your OE type Paper Filter that one can DIY it into the place. This can easily yield +5% performance/FE. The other one comes with its own ‘adaptor’ and it isn’t so much of a DIY and costs 20-25% more, promising another + 2.5 % or so. For further insights into the subject, please surf their following URL -

http://www.methodsonline.com

B - Exhaust Headers
The next but not so simple thing to do is to install custom-built ‘exhaust headers’ AND ‘free-flow’ tail-enders. These for most 4-cyl stock cars can be had for about Rs: 10k or so. The EH’s start with one pipe for each cyl at the exhaust manifold and after a ‘calculated’ length, depending upon the CC of the engine, they merge into 2 and then into 1.

Sometimes, this can create problems for the proper working of the ‘O2 sensor’ of Mpfi’s that has to be relocated, from its OE location bang next to the OE exhaust manifold, to down the line to where all headers unite into one. By which time, the exhaust gases have cooled down a bit and may thus lead the OE/O2 Sensor loosing some of its sting. This in turn can upset/enrich the A/F ratio via the ECU as it’d then ’see’ the engine as running colder than what it actually is - making the FC and CO levels go up for good.

Further, in the process, there’s no room left for the OE fitted/under-chassis Catcon and it has to be dispensed with - which itself costs ~ 12k+. With EU-IV norms round the corner, your otherwise EU-II/III compliant Car will fail PUCC’s with this arrangement as the CO Norms for all road worthy cars then stand to come down from the present 3/1.5% to 0.5% max!

C - Upgrading a Stock Car Engine
Upgrading of a stock Car engine/performance involves the following:

1. ‘Blue-Print’ the Engine.
2. Shave off/lighten the Flywheel as much as possible.
3. Increase its Compression Ratio by ’shaving’ the Cylinder Head suitably and advance ‘Ignition-Timing’ to as much as it can take with 93 Octane ULP.
4. Upgrade Spark Plugs/Performance Air Filters/Cooling System to match.
5. Polish and ‘Tune’ its Air Intake including installation of a ‘Performance’ Air Intake System - to increase its ‘Volumetric Efficiency’ as far as it’d go.
6. Put in a ‘high-lift’/Performance Camshaft and alter ‘valve-timing’ to suit.
7. Put in Free flow/Performance Exhaust ‘Headers’.
8. Re-map the ECU - a Specialised Job.
9. Alter the ‘Final Drive’ Ratio to suit.
10. Put Alloy Wheels/Tyres to suit.
11. ‘Front and Rear-end’ suspension stiffening would be required too - by any one of the various means available.
12. Super or Turbo-Charge the Engine. This one is a lot more complex an issue and we’ll talk about it in one of our next issues.

All these are highly specialised skills and not every other Garage’s cup of tea. A good ‘Pro’ job can set you back by as much as Rs. 30k for the above 1-11 alone, if not more! Besides, such mods should not be attempted while a Car is still under its OE Warranty - for obvious reasons. As to where to get it done, one will have to seek out Garages which prepare Rally Cars. One such is in NCR/Noida and can be reached by surfing http://www.performanceauto.in.

These 2-are as removed from each other as Adam from Eve - but yet compliment each other and are often ignored by an average motorist - especially the former.

Any mass produced wheel (Rim+Tyre/Tube) does not have ‘even’ weight distribution around its 3-axes. Consequently, when it rotates around its own axis, it tends to ‘Vibrate’ - the intensity of which is directly proportional to the degree of unbalance as above AND the rotational Rpm. As a car owner, it’s worthwhile to know that ‘vibration’, like cancer, is the biggest killer in any machine and thus needs to be nipped in the bud.

Such imbalance induced vibrations gain significance with the wheels Dia’s getting smaller for the mini’s and micro-mini’s and yet having higher cruise speeds’ capability. If left ‘un-treated’, they induce annoying steering wobble up front at various speeds - incl damage to the suspension members/bearings all around INCL at the rear. Wobbly wheels up front even affect free-rolling capabilities of a Car and thus eat into its fuel efficiency as well.

Consequently, ‘Dynamic’ Wheel Balancing techniques were developed way back in the ’50s in the West and like all others, are well computerised today. Take your wheels to any ‘tyre-shoppe’ and see them being balanced and you’ll know the rest.

To sum-up, it’s a fallacy that only one’s front wheels need to be balanced, say every 5 kkm under our driving conditions. The fact of life is that one should have all of one’s 5-wheels in good balance all the time, as one never knows when and where one of the 5-wheels may have to be used upfront too.

Wheel Alignment on the other hand is quite a different ball game. In the Amby/Fiat era - with miles of slack in the steering linkages anyway, one got away with the crude method of using a String with a ‘chhotoo’ to assist but not any more. For starters, present day Cars have their front ‘Track’ appreciably wider than the rear to give them the desired high speed cornering ability. To make it worse for the ’string-wallahs’, we now have Cars with independent rear suspension too calling for the rear wheels’ alignment as well!

All this has led to the development of the present ’state of art’ Wheel Alignment m/c’s using infra-red sensors to read/correct the basic parameters of a Car’s f/r suspension systems. Like for wheel balancing, take your wheels to any ‘tyre-shoppe’ and see them being ‘aligned’ and you’ll appreciate why it’s so important to have one’s wheel alignment checked/reset every 10 kkm in our context, if not SOS after hitting a bad pot hole or a rut.

Preamble
A vast majority of car owners, particularly the young ones, have this obsession that the OE Wheels of their new cars aren’t good enough and they need to be upgraded to ‘Alloys’, with wider/fatter tyres to match.

Such a fad needs to be looked into with some hard facts and practicality…

Whether Alloy Wheels:
Alloy Wheels derive their nomenclature as they’re made out of Aluminium Alloys of which Magnesium is a principal ingredient to give it the desired strength - hence the name ‘Mag/Alloy’ Wheels as well. Their manufacturing process basically comprises - a) Pressure die-casting, b) precision machining and c) Finishing by way of powder coating etc. Thus the end product is considerably lighter than their ‘pressed-steel’ counterparts and a lot more ‘true’ in their X-Y-Z axes.

While Alloy Wheels will make a noticeable difference for the better in handling/ride quality, it’s my personal opinion that Alloy Wheels are not for our Pot-Hole ridden Roads and the wayside ‘Hammer and Tongs’ Puncture Repair facilities. If subjected to either, they will be vulnerable to permanent damage by way of chipping and cracking. FYI, more than half of Europe rides on Pressed-Steel Wheels - inspite of the above two limitations not being there. So, what does it prove!

Whether Tubeless Tyres:
A vast majority in the motoring world including the developing countries today rides on Tubeless Tyres coz of the various advantages they offer over Tube types. However, the disadvantages of TLTs in the present Indian scene are that they require:

i) Special puncture repair techniques, tho’ they’re well within the competence of an average DIY person using the ‘Kit’ available for the purpose.

ii) Mechanised tyre mounting/dismounting facilities, to save their special rim/beading from permanent damage.

iii) High pressure compressed air, to suddenly inflate them, so as to be able to quickly and effectively ’seal with the rim’, in case they’ve to be dis/re-mounted for/after puncture repairs.

iv) It’s inadvisable to put in tubes inside once punctured TLTs - for high speed applications - as they wld run hotter than their tube type eqvts coz of greater friction between the TLT’s inner surface. However, it’s recommended to carry a new tube as spare for contingencies during outstation travel.

Even though most of above prerequisites may not yet available in every nook and corner of the Country at the moment, the fact remains that TLTs are the order of the day and a beginning towards it has already been made, with more and more new cars coming in with TLTs as OE fitment.

FYI, on older cars, TLTs can be used on pressed steel rims also PROVIDED they are flawless AND TRUE INSIDE OUT; but once deformed due to a Kerb or pot-hole impact or rust setting in - especially at the insides of filler-neck hole - they will become unsuitable for TLTs.

Altering OE Tyre Specs
Likewise, tampering with the OE Wheel Specs or suspension settings of a Stock Car is far from advisable - as they are arrived at after exhaustive R&D by the OEMs to give best possible results under the most trying conditions that an average motorist is likely to encounter.

On the other hand, altering the designed front and rear ‘Track’ of a Car is a total NO-NO, as all these can lead to annulment of your Warranty and hence the Insurance Cover - should something go wrong!

However, within limits, one can ‘Upsize but NOT Oversize’ but at one’s own risk. The basic funda here is of ‘one-up’ and ‘one-down’. In other words, one can go for the next higher/wider ‘foot print’ but the next lower ‘aspect ratio’ ALSO at the same time - maintaining the OE Rim dia/size - such that the ‘overall’ Wheel Dia doesn’t change by more than (+/-) 5 mm. However, with wider tyres, depending on their size, the ‘J’ size of the Rims too may have to change.

Wider ‘foot-print’ means better handling but at the cost of somewhat higher fuel consumption and stiffer steering and lower ‘Aspect Ratio’ means a stiffer ride/prospects of more rim damage at the cost of better handling/body roll. So the choice is yours!

Preamble
During the last five years, diesel engine technology has seen phenomenal pace of development and turbo-charged ‘common rail direct injection’ systems have become order of the day, giving a full run for their money to their petrol siblings. So, let’s have a look at some typical QnA’s on the subject…

Question and Answer
As a Diesel Car is less environment friendly and has higher maintenance cost, would it not be prudent to get a CNG kit fitted in the car by a reputed manufacturer, even if it affects the warranty of the Car? Please advise. Does loosing the warranty matter much, especially if the car is from a reputed manufacturer? Do the latest Diesel Engines e.g. those of Maruti Swift, Logan and Ford Fusion, in the long run, make noise, pollute more, have a higher maintenance cost etc.? It’s understood that one should be doing 1500 km+/pm for a diesel to be ‘viable’.

For starters, with the state of art ‘common rail direct injection’ technology with ‘multiple pilot injection’ as found in the MUL/Swift-D, diesels today are actually MORE environment friendly AND ‘fuel-efficient’ compared to contemporary petrol engines. In fact, nearly 60% of new cars sold in the EU today are diesels! LPG/CNG are also good ‘green’ fuels but only petrol engines can be converted cost-effectively. Besides, their road side availability any where in the world, leave alone in India, is not as wide spread as diesel.

As far as losing warranty on engine is concerned, it’s far from advisable as if at all some thing goes wrong - the chances of which are bright in retro-fitment of Gas Kits into Mpfi’s, it can set you back by thousands of INRs’. Therefore, it’s a lot wiser to go for vehicles that come OE with such Kits - a number that’s growing steadily over the years.

As for engines of present generation diesel cars getting noisier over the years, a perceptible increase is inevitable due to wear and tear - just like the petrol ones - but other than that, if maintained ‘as per the book’, which is seldom the case with most car owners in India, no abnormal noise levels can arise. Once the warranty is over, people tend to be penny wise pound foolish by stopping from getting their cars serviced at the OE authorised service centres and instead, go to the friendly neighbourhood mechanics - not realising that the present day cars need special hi-tech diagnostic and servicing eqpt. costing lacs of Rs., not to mention the know how - something which the FNM’s can never afford to acquire or have.

Regarding higher maintenance costs as the vehicle gets older, it’s but natural and petrol cars are no exception. It’s one of the reasons why it’s recommended that one should be doing more than 1500 km/pm to ‘qualify’ for a diesel.

Question and Anwser
1. My diesel Zen has done 40,000 kms. It is in for servicing and they want to do engine de-carbonisation. Is it required?

1a) Strictly speaking, decarbonising at this stage/40 kkm is not called for on engines like yours but a lot depends on the quality of diesel fuel used. What you should ask your MASS is as to how they propose to do the de-carb. If it’s going to be by lifting the cyl head and mechanically scrapping the combustion chamber/piston tops’ deposits BUT leaving an about 3-5 mm ‘ring’ of carbon deposits around their periphery/cylinder walls, then it may be done. But on the other hand, if they’re going to do it by hooking on some m/c with solvents etc and then run the engine on it for 1/2 an hr or so, then it’s NOT advisable coz it can lead to some serious problems of loss of compression later on.

1b) In addition to above, the vehicle’s ‘exhaust line’ should be manually decarbonised. This can be done by taking it out completely, ‘tapping’ well the catcon and the mufflers with a rubber/wooden mallet to dislodge their internal carbon deposits and then flushing them out with high pressure water hose shoved in at the engine end till clear water starts flowing out of its tail end.

2. Do you recommend any more special work/check to be done during servicing, in addition to what is in the Manual?

2a) In addition to these, you should also ask the garage to change your ‘valve timing belt’ at this stage, to pre-empt its snapping in foreseeable future. For, if it snaps while the engine is running, it can cause a lot of expensive internal damage to an engine like yours. Unfortunately, such belts don’t come cheap - over Rs: 1,000/- but it’d be money well spent.

2b) Besides this, you should also ask your garage to reset the various/8-nos ‘valve clearances’ at this stage, as they’re bound to have reduced over the limit due to wear on the valve seats. If allowed to continue with such reduced clearances, burning out of exhaust valves in particular cannot be ruled out in near future - again an expensive and a cumbersome procedure to fix.

Preamble
It won’t be any exaggeration to say that the importance of Automotive Lubricants in the well being of vehicles is more often than not fully appreciated. Suffice to say they’re what blood is to the human body…

An average Car essentially has 4-types of Oils/Lubricants to keep it running smoothly and enable it give it’s max useful life. These are -

1) Engine Oil, 2) Gearbox Oil, 3) Brake Fluid/Oil and 4) Coolant - which also serves as a lubricant for the Water Pump Seals.

The ‘Grade/Viscosity’ Specifications of these four along with their recommended Time/Kms change intervals are invariably given in the respective Owners Manual of a Car - as these can vary from make/models. Please study yours and figure them out accordingly.

In general, all these should be of reputed Brands, ensured not to be spurious and always bought in pilfer-proof sealed packaging. Buying them loose at petrol pumps etc for ‘topping-up’ should be avoided as these are often adulterated/contaminated and therefore, one should always carry one’s own - either as left over’s of sealed packs purchased earlier for replacements or topping-up.

As far as Engine oil is concerned, its change at the prescribed time/distance interval should always be accompanied by change of the recommended Brand/Grade of Oil Filter also. A lot of people are under the mistaken belief that as far as EO/F is concerned, distance alone matters.

Quite to the contrary, it’s the time interval here which is the over-riding factor - usually 6-months for mineral based oils in our dusty climate - regardless of the distance covered if less than the prescribed limit - as EO’s once poured-in are vulnerable to deterioration due to oxidation/contamination by the by-products of fuel combustion inside the Cylinders. The same goes for the other three due to other atmospheric/operational factors.

In general, the recommended change intervals for Engine Oils is 7.5 kkm/6-months, MT/GBs 20 kkm or 2-yrs, Brake Fluid 18-months and Coolants 30 kkm/18-24 months.

Whether Synthetic Engine Oils.
Synthetic Oils are the ‘Ultimate’ Lubricants available in the World today and to the best of my knowledge, ‘Mobil-1′ is the only ‘official one’ in India. Regrettably, most retailers don’t stock it as it costs ~ Rs: 550/- a litre and the takers are very few. Besides, at this cost, the chances of it being spurious are also quite high.

On the flip side, given our Operating Environment, S/O’s can easily go > 3x the otherwise recommended drain interval for the conventional Oils - time as well as distance.

The next best option I’ve come across is the ‘Castrol-Magnatec’ at < half the cost. With this, one can safely do 1-1/2 times the distance/time on the recommended drain intervals.

However, for general info, it may be noted that Synthetic Oils are not recommended for new/under 'running-in' Engines, to enable them fully 'bed-in'. Further, as practically all new Cars today come with Warrantees upto 2- yrs/40 kkm, during this period the OEMs don't permit using any Oils supplied by Customers - for understandable reasons - unless your Dealer is prepared to put-in these at your cost - which he won't!

Whether Engine Oil Additives;
Let’s start by understanding what exactly it is that lube oil does inside your engine.

An engine oil’s job is primarily to stop all the metal surfaces in your engine from grinding against each other and tearing themselves apart. But it also has to dissipate the heat generated from this friction as well. It, therefore, also transfers heat away from critical areas during the combustion cycle.

Another function of engine oil is that it must be able to ‘suspend’ the by-products of fuel combustion, such as silica (silicon oxide) and acids. It must also clean the engine of such by-products. And it must do all of these things under tremendous heat and pressure without succumbing to fatigue or loss of thermal viscosity.

The fact of the matter is that the companies who manufacture and process petroleum and synthetic engine oils already have ‘additives’ to do exactly what is needed for the application it is designated for.

Although some Engine Oil Additives may not contain anything harmful to your engine, and even some things that could be beneficial, most experts still recommend that you avoid their use. The reason for this is that your oil, as purchased from one of the major oil companies, already contains a very extensive additive package. This combination of ‘additives’ that the oil manufacturer has combined are ’synergetic’ - which means that some of the individual components will only react mutually, achieving a reaction none of the components alone could otherwise achieve.

If you add to or change this formulation, the effect the original formulation that was meant to achieve the ultimate objective may be upset, even if it’s more of something the formulation already contained.

In the case of engine oil additives, there is a considerable volume of evidence against their effectiveness. This evidence comes from well-known and identifiable expert sources, including independent research laboratories, state universities, major engine manufacturers, and even NASA.

No matter what the additive makers would like you to believe, nothing has been proven to totally stop normal engine wear – not even the ‘slipperiest’ PTFE kind – as they can cause oil starvation! This is particularly true in the area of piston rings and Oil Filters, where there is a critical need for adequate oil flow. In practically all of the reports and studies on oil additives, and particularly those involving suspended solids like PTFE, this has been reported as a major area of engine damage.

Preamble
The invention of a ‘Re-chargeable Cell’ by the 1920’s revolutionized the way cars work today. Until then, they had engine driven ‘Magneto’s which became a source of electrical power for the car’s ignition and lighting systems only when the engine was manually cranked to a ’start’. Consequently, every thing electrical in it went dead the moment its engine stopped running.

So here’s some more on the subject…

Car batteries are ‘Lead-Acid’ type ‘Secondary-Cells’ i.e. re-chargeable and today besides the entry level ‘regular’ ones, they come in variants such as low maintenance types to totally sealed types - requiring minimal to no topping up at all during their useful life of 3-5 years.

There is no National or International Standard which lays down the criteria for ‘Power’ of a Storage Battery - coz of the very nature of the ‘device’ - since ‘Power’ is defined as ‘Rate of doing Work’ which in turn is measured in Units of ‘Watts’ or ‘Hp’ continuously or indefinitely – say like a Ceiling Fan.

Therefore, Storage Batteries are universally given an ‘Ampere-Hour’ rating at a ’specified’ rate of ‘current’ discharge against their designated terminal voltage.

In other words, a ‘C5/38AH’ Capacity of a Car Battery means that it can sustain a discharge rate of ‘5 Amps’ for 38/5 = 7.6 hrs, before it gets discharged for all practical purposes BUT is good enough for a re-charge. This level for a 12 V Car Battery occurs when its terminal voltage sinks to ~ 10.8 Volts - from a ‘fully charged’ one of 13.2 Volts.

On Cars fitted with Alternators, adequate charging is easy to test by using a DC Voltmeter and here’s how the Battery Service people do it -

i) The Battery terminal voltage with engine idling with all loads off should not be < 13 volts and at an engine rpm of 3000, it should not be > than 15 Volts.

ii) Likewise, with all loads on, it should not be < 12 volts at idling and < 13.0 volts @ 3000 rpm.

iii) The Battery Terminal voltage should not drop to < 9 Volts when the starter is cranked.

iv) The Specific Gravity of 'each' Battery 'Cell' should not be < 11.80 the first thing in the morning. If it does on an otherwise healthy battery, then it’s logical to suspect that there’s unhealthy ‘leakage’ in the Car’s electrical system.

v) The correct way to check for leakage is to - a) Take off the Batt (-)ve Terminal and b) insert a 0-1000 mA range Ammeter between it and a good body earth point - such as the GB Housing where the earth cable is normally clamped - with all the loads switched off. Any current indication of > 25 mA would be a cause for concern.

vi) Likewise, a supplementary Alternator charging check is done by introducing a 0-30A Range Ammeter in the ‘Main Fuse’ ckt and see that it kicks upto 30A soon after a self-start and then gradually tapers down to 5A or below after a while.

vii) A precaution one should take would be NOT to sw off the engine at every traffic light and then restart - remembering that after every self-start, a Car needs to be driven for atleast 10 mins non-stop for the Battery to fully re-coup. This way, one can considerably enhance not only the Battery life but also that of the Starter Motor.

viii) Similarly, ensure that your cabin roof/boot light doesn’t remain on overnight by any chance - whether visible or not. Faulty door switches are often the cause.

With all these things in place, there’s no reason for a new Battery to be running down frequently. There has to be a leakage or lack of adequate charging somewhere – unless ofcourse the battery is faulty. The average battery life of a well maintained car in our climate is ~ 3-yrs. If inspite of the Car’s electrical/charging system and starter motor being OK, the engine doesn’t crank, in all probability the battery is half dead or has lived its life.

An authorised battery service station or a competent garage can further confirm this by checking the specific gravity of the electrolyte in each one of it 6-cells, followed by a ‘heavy current discharge test’ using a gadget for the purpose. If the battery voltage sinks below 9 volts during this test, the battery is either discharged or dead, depending upon its age.