Preface

In Part-V of this 'series', I shared with you some of my thoughts and decades of experience about the problems one can come across while operating and maintaining one's Car - as the true 'ownership experience' of any make/model begins and ends here.

          With this info at the back of one's mind, let me share with you some more aspects of the same theme.

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1) Owners Handbook

It’s, therefore, of utmost importance that one goes through the Owners Handbook from cover to cover w/o further delay, as it'll do you and your car a lot of good. Nothing could be more unwise than to think that a car requires no maintenance after its free/warranty services.

Most such OHB’s lay down detailed Maintenance Schedules on time/distance basis right upto 80,000 kms or 4-yrs, whichever occurs first, and thereafter start from the beginning all over again. It’s only logical to surmise that such requirement vary from make to make and model to model.

To sum-up, it makes a lot of sense to meticulously stick to such OE recommendations – with the ultimate objective of having a long lasting AND a reliable car. When so maintained, it’ll turn out to be cost effective in the long run.

2) Rolling Noises

To check on rolling noises, as distinctly different than tyre-tread noises, accelerate the car to about 50-60 kph on a good/smooth/quiet road with all windows rolled up, AC/Music System/Blower and any other human chatter shut off. Shift to neutral, switch off the engine ‘ignition’ ONLY so as NOT to lock the steering and be prepared for loss of servo assist to brakes when the engine is so sw'd off.

Let the car 'coast' now. The 'humming' kind of noises one would then hear are the 'rolling noises'.

These are partly comprise - i) tyre/tread/road noise and ii) Car's 'Structural Resonance' as a result of (i). Such rolling noises in some of even new cars can get to real headache proportions at high cruising speeds, say > 80 kph.

An averagely keen motorist should be able to distinguish between the two. Many people have reported the above (ii) as excessive in some Sedans that’s not expected in a car of that class. This is an issue that one should really keep in mind while test-driving before deciding to buy a new car where, more often than not, it could be an incurable design defect.

On the other hand in used/older cars, such/excessive rolling noises can arise due to – a) unevenly worn out tyres, b) dynamically out of balance wheels and c) worn out wheel bearings. Fortunately, all these are relatively easier to get fixed.

3) When to overhaul an engine

The confirming symptoms of a worn out engine are - a) continuous emission of blue-gray smoke - even after warming up, b) Oil consumption exceeding, say, 1/2 lr per 1000 kms, c) starting difficulties - especially when cold and d) Loss of power.

All these can then be capped by a 'dry 'compression' test at a reputed Garage. If the readings come out to be, say, < 10 kg/sqcm with > 1.0 kg/sqcm variation amongst cylinders, then your engine is worn out.

Overhauling it in a nutshell means renewing all its internals prone to wear such as pistons/rings, bearings, valves, oil pump, cyl liners - either with new 'sleeves' or by 're-boring', water pump etc. A good job even for a 3-cyl engine like the M800 can cost upwards of Rs: 10k.

On the other hand, if the dry compression test does not reveal excessive wear, then prima-facie it can be a case of engine oil finding its way into the combustion chambers more via the valve oil seals than worn out piston/rings. Such seals can be easily replaced at a fraction of the cost and in about a day’s time.

4) Excessive vibrations in a new engine

A recently overhauled engine can vibrate abnormally while idling due to any of the following reasons :

a) General stiffness - calling for higher internal power to run the engine in that mode. This gradually subsides as the engine 'runs-in' - usually after a 1000 kms of careful driving - at engine rpm's not exceeding eqvt of 60 kph in the 4th gear.

b) lower than rated idling rpm - which for most 4-cyl cars is around 800-850.

c) Over-lean A/F mixture in Carb types - should be set to 1.5-2% 'CO' when hot.

d) Inter-cylinder compression pressures varying more that +/- 1 kg cm.

e) Valve clearances varying between cyls by more than +/- 0.05 mm over and above the ones recommended by the OEM.

f) Faulty Spark Plugs/HT leads.

To overcome (a) above, it's a good practice to use the 'ready-mix' 2-T petrol for such/carburettor type engines during their first 500 kms. It may be noted that this is NOT recommended for Mpfi’s, as their ‘in-tank’ electric fuel pump may not be able to handle such a ‘mixture’ and may consequently burn out – some thing one can ill-afford due to high replacement costs involved.