How to Inspect the Engine When Purchasing a Used Car

The condition of the engine is critical when purchasing a used car because engine problems are costly to repair. Because it is difficult to evaluate the mechanical condition of the engine during a quick test drive, we recommend having a used car thoroughly inspected by a qualified mechanic before signing the contract. Here are some pointers to look for when inspecting a used car for signs of engine problems or a lack of maintenance.It is difficult to assess the mechanical condition of the engine during a quick test drive, which is why we recommend having a used car thoroughly inspected by a qualified mechanic before signing a contract.

We have been in the automotive industry since 1984, ranging from apprentice to master technician, workshop foreman, controller, service advisor and service manager, in numerous premium vehicle businesses. We have built a level of loyalty that in the 21st Century is vital. After all, customer service and care is a point of difference.

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Here are some pointers to look for when inspecting a used car for signs of engine problems or a lack of maintenance.

Examine service records

Although service records are not always available, it is helpful if the dealer or person selling the car can provide proof that the vehicle has been maintained on a regular basis. Look for oil changes and mileage records if you have access to the service records. It’s a plus if you can prove that oil changes were performed on a regular basis. Oil change intervals range from 5000km to 30000km depending on the manufacturer, but may also be based on time, 6 monthly or yearly, irrespective of km travelled.If the vehicle has been driven for a long period of time without an oil change, the engine may be worn on the inside. It’s also a good idea to know if the timing belt (if the car has one) has been changed, as well as what other maintenance has been performed.

Examine what’s under the Bonnet

Before you start looking under the bonnet, make sure the engine is turned off, the transmission is in “Park,” and the parking brake is engaged. Leaks, the smell of burnt oil or antifreeze, signs of poor quality repairs or lack of maintenance, and ‘racing’ modifications are all things to look for. Before showing a used car to a potential buyer, dealers frequently clean the engine bay. This means that just because everything is clean and shiny doesn’t mean the engine is in good shape. Let’s look at some examples:

Burnt oil smell under the bonnet

Repairing oil leaks isn’t always inexpensive. As the mileage increases, the piston rings and cylinders wear out, allowing more blow-by gases to enter the crankcase. This raises the pressure within the crankcase. As a result, the oil is forced out via various seals and gaskets, as well as the PCV (crankcase ventilation) system. This problem is more common in turbocharged engines. A well-maintained engine is unlikely to have any leaks.

Visible oil leaks

Oil leaks may not be visible from beneath the bonnet, but here’s a tip: look from beneath. Use your phone to take a photo or video. Examine the engine and transmission’s lower parts. Everything must be completely dry.

Leaks of coolant and other fluids

If a vehicle runs perfectly, but there is a coolant leak from the radiator, then this vehicle requires a new radiator at the very least. But a cracked radiator can be a sign of more serious issues. It is best to avoid buying used cars with this type of problem.

Low oil level, contaminated oil

Checking the oil condition on the dipstick can reveal a lot. The engine must be turned off in order to check the oil. Set the parking brake, but be cautious because some engine parts may be hot. The owner’s manual in the car contains instructions for checking the engine oil. If the oil level is low, it indicates that the engine is consuming oil or that it has been a long time since the last oil change. When the engine’s oil supply is depleted, it wears out faster.

Check under the oil cap while the engine is turned off

Remove the oil filler cap while the parking brake is applied and the engine is turned off. Take care, it may be hot; use a towel or rag. Examine it with a flashlight. Some engines have visible internal components. If you aren’t sure about performing this test, it is best to hand it over to your mechanic.

Keep an eye out for performance mods

If a vehicle has been modified for performance, proceed with caution. Modifications, when done correctly, can improve the performance of a vehicle. Poorly done engine mods, on the other hand, can cause a slew of issues, especially if parts that were originally on the vehicle are no longer available. If the vehicle has been modified, it has most likely been raced or otherwise abused.

Is there a timing belt on the engine?

Some vehicles use a timing chain rather than a timing belt. Timing belts in most cars need to be replaced between 90000km and 18000km, but also sometimes time factors come in and maybe 4-8years irrespective of km. A timing belt replacement costs between $800 -$1800 in a 4-cylinder engine and $2000 to $3500 or more in a 6 cylinder engine. If the car you want to buy has a timing belt, find out if it has been replaced. When a timing belt is replaced, some mechanics apply a sticker to the engine. A timing belt is hidden under the covers and cannot be seen under the bonnet. Your mechanic will need to remove one or two covers to inspect its condition, which is not always easy. Checking the service records to see if a timing belt has been replaced is a more realistic option.

Many hidden problems can be revealed by a cold start

Starting the engine cold is the best way to detect hidden engine problems. It might be a good idea to arrive at the dealer a little earlier than your appointment time to accomplish this. You will also know if the battery is in good condition, because if the battery is old, it may need to be boosted in order for the car to start. When starting the engine, keep an eye out for engine noises and smoke. Look for another vehicle if the engine rattles or makes other loud noises, or if there is blue smoke coming from the exhaust. The blue-grey smoke from the exhaust of the car in the photo, for example, was visible. It also smelled like burning oil. Blue smoke indicates that the engine is burning oil.

Test drive

When you start the car, all of the warning lights on the dashboard should turn off. If the engine symbol (Check Engine) light or Service Engine Soon light remains illuminated, the engine computer has detected a fault.It could be a minor issue, but it could also be a costly one. There is no way to know how serious the problem is unless the vehicle is properly diagnosed.

During the test drive, keep an eye out for engine noises, vibration, a lack of power, or any other issues with driveability. When the engine is started, it should run smoothly, with no shaking or hesitation. There is a problem if you notice the engine hesitating or stumbling when accelerating. Idle speed should also be consistent. Test drive the vehicle for as long as possible; problems may not be apparent after a quick drive around the block. It is advantageous to be able to test drive in all modes: acceleration, deceleration, stop-and-go traffic, and highway cruising.

Keep an eye out for the engine temperature displayed on the dash. After the engine has warmed up, the temperature gauge should remain in the middle of the scale.
Even if everything appears to be in order, we strongly advise having the used car thoroughly inspected by an independent mechanic before purchasing.

If you are looking for the best pre-purchase car inspector in Melbourne, do not hesitate to contact German Precision or Prepurchase Check today!

Source: samarins.com