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5 Ways To Know If A Car Engine Has Been Changed

Whether you have recently bought a classic car and want to make sure it is the real deal, or if you are simply interested in finding out more about the originality of your own car, an interesting place to start is to find out whether or not the engine has been changed.

The 5 signs that a car engine has been changed are:

  1. It has a different VIN number
  2. It isn’t the right engine
  3. The cylinders have been reshaped
  4. The engine looks new
  5. Inconsistent documentation

If you pay attention to each of these potential signs, you will be able to spot a changed engine. This can be very valuable knowledge if you are looking to buy or sell a car, so keep reading to find out more.

Why Should You Care If An Engine Has Been Changed?

Implications On Value

So, why might you want to know if your car engine has been changed in the first place? For some, it will make the car more valuable if the engine has been changed, as a newer engine block can mean some decent money has been spent on the car, and it is statistically less likely to fail in the near future than an older one.

However, if it is the age of the car which gives it its value, such is the case for classic cars, then you will be looking to see as much originality as possible, not least with the engine. The engine is the heaviest part of the car, and it can be the most valuable on its own too. It is worth knowing whether it is original as it will allow you to sell it for the highest price (or the lowest).

Classic Cars

This information can be just as useful if you are a buyer. If you are able to check out the car in a depth before you buy, you will be able to find out if the engine is original. If so, you can benefit from the above reasons but the other way around. For classic cars you get more value with original engines, and for newer cars you can probably trust them more if the engine is new too.

If you already own the car, and are not looking to sell it, you can benefit from knowing if the engine is original too. If it is, and the car is fairly old, you may wish to have it checked out by a mechanic for potential issues. This might not be cheap, but it could be more expensive down the line if the underlying problems lead to issues elsewhere in the car.

Why Was It Changed?

Conversely, if the engine was changed, you may want to know why. Was there a problem with the original engine? Was it replaced by a trained professional? Is there a warranty for the replacement? All of these questions are important, and if you find that the engine was replaced, it will be worth finding out these answers in case there may be something wrong with your car.

Finally, you might just want to know so that you learn more about your car. It is simple enough to find out if the engine has been changed, and it may give you some peace of mind or simply teach you something you didn’t know by finding out. So, how do you find out if a car engine has been changed?

The 5 Signs That A Car Engine Has Been Changed

1. It Has A Different VIN Number

This is the most reliable and most common reason for noticing an engine has been changed. VIN stands for Vehicle Identification Number, and it is essentially a serial number that identifies the car’s parts. There will be a VIN number located on various components, such as the chassis, gearbox and, of course, the engine.

Knowing Where To Look

You can check for a VIN number in different places on different cars, but there will usually be one on the underside of the engine block. You might need to get under the car to see this, and so while it might be easy to do on a car you already own, it could prove difficult on a prospective purchase. If you can, ask the dealer or seller if they can identify the VIN number for you.

This VIN number would then need to be matched to the VIN number on another part of the car, ideally the body of the car. Sometimes you can find it on the lower portion of the windshield on the drivers’ side, but the exact locations vary between manufacturers. The same thing applies to the VIN number on the engine, as it could be on many different parts of it.

Check The Documentation

You may also find references to the VIN number in the vehicle’s documentation. When you do find the numbers, if they match then the engine is original. If they don’t match, then the engine has been replaced. It’s as simple as that. Older cars may not have VIN numbers, but instead a serial number, but the same matching principle applies.

2. It Isn’t The Right Engine

This may sound a little odd, but it could be as simple as the engine not being the right one for the specific model of car. For example, if you were expecting to buy a car with a V6 engine and you take a look under the hood and it’s a V8, you will know the engine has been changed. This is unlikely to happen without you being told the car has been upgraded beforehand of course.

Serious Implications

But this could have serious implications on your insurance premiums, as the car is not meant to be driven with a different kind of engine, and thus it poses as a liability to insurers. You could also find it to go the opposite way, where you would be sacrificing power and quality, or you could just find a different type or model of engine than the type for which the car was built.

3. The Cylinders Have Been Reshaped

This is a far more difficult sign to check yourself, and so you will need to get a mechanic to help you out. If your engine has been rebuilt rather than replaced, it may have had its cylinders reshaped. Over time, cylinders can lose their shape, and so cars that have a lot of miles on the clock but have remarkably smooth cylinders may have been rebuilt.

4. The Engine Looks New

Another simple but effective sign that a car engine has been replaced is if it looks much newer than the rest of the car. Some people go to great lengths to preserve every part of their vehicles, especially classic cars. However, over time, mother nature and internal combustion eventually take their toll, leaving the engine looking less shiny and perhaps even visibly scarred from years of use.

Not Always Obvious

The surrounding components of the car will also look aged, and so if an engine looks in remarkably good condition when compared to the rest of the vehicle, there is a high chance it is not the original. Look for differences in the paintwork, scratches and bumps and the overall condition of the engine. You may need more information to be sure, however.

5. Inconsistent Documentation

If your car engine has been replaced, there should be a paper trail that leads to the people that replaced it. If it has been simply maintained over time and serviced, then the same rule applies. If you can’t find any paperwork but suspect the engine has been changed, ask the seller for maintenance receipts, as these will indicate if the car has had its engine changed or not.

Final Thoughts

Knowing whether or not your car engine has been changed can be very valuable whether you are a buyer or a seller, and so it is worth finding out if you can. The best way to find out if a car engine has been changed is by matching up the VIN numbers for the car. If not, then you can always simply ask whoever sold the car to you for maintenance receipts to find out.