Saturday, July 16, 2011

Advanced tips while buying a second hand car





So you have finally made up your mind to go in for a second hand car. Congratulations :) However before you continue reading any further I'd advise you to go through the Basic Tips first so that this makes some sense.



1.       Roll on Test

a.       Bottom End Grunt
                                                               i.            Steps: Put car in 3rd gear – slow down to 20kmph and then accelerate to 80kmph. Keep accelerator pressed down completely.
                                                             ii.            Checks - The car should accelerate cleanly. There should be no unexpected jerks, loss of power.
                                                            iii.            Problems – Poor fuel metering, air cleaner clogged, engine not in tune.
                                                           iv.            Interpretation: Poor maintenance, car has not been taken care of properly – regular services may not have been carried out.

b.      Mid Range:
                                                               i.       Steps: Put car in 4th gear – slow down to 40kmph then accelerate to 100. Keep accelerator pressed down completely.
                                                             ii.      Checks – The car should accelerate cleanly. There should be no unexpected jerks, loss of power.
                                                            iii.      Problems - Poor fuel metering, air cleaner clogged, engine not in tune, Valves noise
                                                           iv.      Interpretation - Poor maintenance, car has not been taken care of properly – regular services may not have been carried out.


2.       Clutch Condition:

a.       Clutch Slippage: Clutch should not feel hard
                                                               i.      Steps: Depress clutch. Put car in reverse. Ensure there is no traffic or obstruction behind. Increase revs to 3500. Dump clutch. Stop after 3 – 4 seconds. OR Put car in first gear drive slowly till engine rpm is in mid range. Then accelerate hard all the way up to the top.
                                                             ii.      Checks: If car does not accelerate in keeping with revs then there may be clutch slippage. Some slippage will occur due to spinning wheels. Other than that the car should accelerate properly.
                                                            iii.       Problems: Clutch plate could be worn. Clutch might need setting.


3.       Gearbox

a.       Shifting

                                                               i.      Steps: Accelerate hard in first gear and quickly shift to second. Try down shifting from third to second as well.
                                                             ii.      Checks: Does the gear shift without baulking? Does it make a grinding sound? Does it slip out when under load.
                                                            iii.      Problems: This could be a problem with the synchromesh, or the gear lock.
                                                           iv.      Interpretation: Depends on the life of the vehicle, but by and large this means that the vehicle has been used roughly and maintenance has not been in keeping with the usage.

b.       Auto’ box – Planetary

                                                               i.      Steps: accelerate


4.       Steering

a.       Joints
                                                               i.      Steps: Go to a place where you can make constant radius turns. Drive slowly, put the car in first. Turn the steering wheel completely to the right and accelerate. Keep increasing speed for a couple of rounds. Do the same for the other side.
                                                             ii.      Checks: Listen for any knocking or clicking sounds.
                                                            iii.      Problem: The constant velocity joints could be worn. This is a rare occurrence in modern day cars. For most modern day cars this will be a rare occurrence since CV joints are fairly durable as long as the boot is not torn. Check for boot replacement or
                                                           iv.      Interpretation: Car has been driven for well over 40,000kms to get this kind of a problem. And it hasn’t been cared for. Replacing and servicing joints is fairly expensive.


5.        Engine Bay Inspection

Open the hood. Look for hood release latch, do not grope for it. Each car’s will be different. Ensure stay is securely on.

a.       Internal parts
                                                               i.      Using flashlight look at cams, valve springs, rockers.
                                                             ii.      They should be shiny and metallic
                                                            iii.      Coating of thick oil is a sign of poor maintenance and possible problems
                                                           iv.      Uneven wear is also not a good sign

Engine oil Condition
                                                               i.      Remove oil dipstick. Take oil between index finger and thumb.
                                                             ii.      Colour –
1.       It should not be dark black. Most oils will look dark after a few 100kms. But that is alright.
2.       Golden colour is a sign of fresh oil

a.       Viscosity
                                                               i.      Is it too thick?
1.       The oils should feel slick
2.       It should not feel watery

b.      Levels
                                                               i.      Wipe dipstick with cloth.
                                                             ii.      Reinsert completely into slot.
                                                            iii.      Pull out slowly
                                                           iv.      The oil line should be between the markings

c.      Particles
                                                               i.      Oil can have sediments
                                                             ii.      Oil can have metal particles

Brake Oil
                                                               i.      Open Master cylinder reservoir
                                                             ii.      Remove filter net
                                                            iii.      Check bottom of container for dirt
                                                           iv.      Check levels with markings on container

Power steering oil
                                                               i.      Open container
                                                             ii.      Check for sediments, dirt
                                                            iii.      Check for levels on container
1.       Note: in some cars like the Honda City and Maruti Swift – the steering assist is electrical so there won’t be any power steering oil.

Coolant Check
                                                                     i.                        Levels
1.       Match liquid level with markings on container
                                                                   ii.                        Condition
1.       Anti-freeze will be mixed with water, but proportion should be correct. A light green/ blue colour means low mix
a.       A proper mix will look dark and thick
2.       Look for traces of oil in the coolant – this will be seen as a light haze on top of the coolant
a.       Check same at radiator cap

Engine Leakages
                                                               i.      Oil leakages at the head
                                                             ii.      Oil leakage at sump
                                                            iii.      Oil leakage – others

Signs of rebuild
                                                               i.      You will be able to find the gasket maker at the joins between the two planes.


Disclaimer: These are just my thoughts and that I will not be responsible for any incorrect decision taken by you or any irreparable loss caused by following these tips. I still suggest you take a second opinion from a professional mechanic.

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