How to check the car engine when buying a used car

smother

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  • Jan 27, 2009
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    How to check the car engine when buying a used car

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    Imagine, you are shopping for a used car. You enter the dealership and see that nice-looking car. You love it from a first sight. Meanwhile, the salesperson hanging around and telling you that regular story that, the car was lady driven and the engine works like a clock, and this is only "Today special" - "We need to clean inventory!", and you are so lucky because they are selling it very cheap - "We even lose money on this deal!" and that you have to give a deposit right now or else you will regret about it for the rest of your life! - Sounds familiar so far?
    You decided - "deal!" - shaking hands, you're happy, salesperson is happy. Finally, you got your new wheels.
    Few weeks later you notice blue smoke when you're starting the car in the morning. Few months later you discover that there is no oil left in the engine and finally got your car towed to the garage. "The engine is gone - has to be rebuilt" they diagnose.
    In fact it's quite common scenario.
    This article will give you an idea an may help you to avoid such a troubles buying a used car.
    However, it's always good idea to have the vehicle inspected by a specialist prior purchase. This is what I'd recommend to any used car buyer
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    Things you should know before going to check a used car

    When buying a used car, without a doubt, first check a car history records. Some cars may have been flooded - worthless to buy. Others were written off by insurance due to serious accident. Many cars have altered mileage, and so on.
    If looking at the used car you noted any problem with the engine (e.g: major oil leak or strong noise) or any abnormal behavior don't let the salesperson to mislead you. They may tell you, for example, that the leak is "overflow from the recent oil change" or "the noise will disappear later by itself or something like this". Generally, such defects never disappear by itself. If you have hesitation, move on - there are so many cars available.
    Ask for service records if they are available. Look for oil change intervals - was the oil changed regularly? I mean driving 1,000 miles over suggested oil change interval won't cause a big damage, but, for example, 9,000-12,000 miles (15,000-20,000 km) without an oil change may cause serious engine problems in the future.
    How to check the oil

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    Park the car on a level spot, turn the engine off and set the hand brake. Locate the engine oil dipstick, pull it out, wipe it off with clean cloth and insert it back. Pull it out again and have a close look. If you've never checked the oil level before,
    If you find the oil is completely black (although for the Diesel engine black oil is normal) and (or) the oil level is very low (left picture) - suspect excessive oil consumption and (or) lack of maintenance. In either case the engine will more likely to have problems in the future. Another sign of poor maintenance would be dark stains (carbon deposits) covering the oil dipstick along its length.
    Well maintained engine will more likely to have cleaner oil and the proper oil level (right picture), although this doesn't necessarily mean that the engine is in good shape; the oil just could have been changed recently.

    Look for leaks

    Look for possible oil leaks. If the engine looks very clean and shiny it doesn't mean it has no leaks. Probably it has been shampooed. Most of the dealers shampoo the engine before putting a used car for sale. But there is the trick - look underneath the vehicle using your flashlight. Check the lower part of the engine and transmission. Everything has to be dry. There might be slight wetness which is not that bad, but there should be no leaks. See any leaks? Oil drops on the parking space? - this may indicate a problem.

    If it's possible, look at the internal parts through the oil filler neck (Don't open the oil cap while the engine is running!)

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    With the engine turned off, try to open the engine oil cap and look inside through the oil filler hole. Use a small flashlight. If it's possible to see any internal parts there, check their condition. What you are looking for is the oil sludge - this thick black buildup on internal parts you can see on the lower photo (this is how the sludged up engine looks inside, with the valve cover removed). If you see a lot of black oil sludge buildup inside the engine it means that either the engine oil hasn't been changed for a long time, or the engine has been overheated, or poor quality oil was used.
    In either case, avoid buying such a car - sooner or later it will have serious engine problems.
    Well maintained engine usually looks pretty clean inside; if you check few cars of the same model it's easy to see the difference. However, again, if the engine looks clean inside it doesn't mean that it has no other possible problems - as a last step, have the vehicle inspected by a mechanic of your choice.