Replacing an engine is one of the most challenging jobs you can do on a car, and consequently the window of error is huge. And to further complicate matters, it’s hard to tell if the motor is in good condition until after it’s installed. Still, there are a few things you can do to make sure the engine doesn’t fail after 10,000 miles or sooner and to check if it’s okay to begin with.
After you replace the engine, start it up and let it run for a while before driving it to make sure everything works as it should. If all is well, the engine runs fine, smokes, and there are no leaks, it’s time for preventative maintenance. The first thing you should do is an oil and filter change before moving forward.
But before we get into more detail about which parts you should replace and why, here are some things to look out for when starting a new engine for the first time.
What to check when starting an engine for the first time
There are several things that can go wrong with a first start after an engine replacement. And while some will show up right away, others might take time. Therefore, to properly perform these pre-flight checks, start the engine and let it run until it is fully warmed up.
Then turn off the engine and allow it to cool down before turning it back on and waiting for the temperature to rise again. And if there are no obvious signs that something is wrong, take the car for a 30-40 mile drive.
excessive heating
Overheating will only show after a couple of minutes of operation. Now, don’t let the engine run without constantly monitoring the temperature gauge. That’s crucial because it’s often enough for the engine to overheat once and be permanently damaged. So watch the temperature rise and you have to stop in the middle. Should it start to rise, the radiator fan should come on and bring the temperature down.
If the engine starts to overheat, check the coolant level first, and then the thermostat and water pump. However, if the coolant is missing, check for leaks under the car. If not, it is most likely a blown head gasket.
smoke out of exhaust
First, if you notice smoke coming from the exhaust, make sure it’s not just condensation, which is likely if it’s cold. However, denser white, blue or gray smoke usually indicates that the engine is burning oil. Now, there are a number of reasons why that could happen, but most often it’s bad valve seals, a blown head gasket, a bad PCV valve, and worn piston rings.
But on a lighter note, it could be that you’ve put too much oil in the engine, and also, if it’s black smoke, then it’s probably nothing too serious. On gasoline engines, black smoke means the engine is running rich, which often means a bad O2 or MAF sensor. In the case of diesel engines, on the other hand, it is normal for some black smoke to come out after the engine has been sitting for a while.
warning lights
Dashboard warning lights, like the more common check engine light, don’t necessarily have to indicate a serious problem. However, it is in your best interest to scan the trouble codes as soon as possible and not run the engine before doing so. Although it’s probably a vacuum leak, bad O2 sensor, or something similar, it could also be incorrect cam timing.
And since bad timing can mean that the timing belt/chain is stretched or the tensioner is bad, your engine could quickly be destroyed. And not to mention that many other things can lead to the same result without showing any obvious symptoms.
Engine running rough
It is normal for the engine to run a little rough after the first start. However, if it doesn’t normalize after a couple of minutes, there is most likely a problem. That’s especially true if the engine runs rough after warming up. Unfortunately, it’s hard to say what could cause this because there are so many potential reasons. However, a quick scan with an OBD tool will likely reveal the culprit.
fluid leaks
When discovering a fluid leak, the first thing to do is to correctly identify it. You can do this by checking the color, smell, and taste of the liquid. Gasoline or diesel will have a distinctive odor and engine oil is golden in color while transmission fluid is usually red. As for the coolant, the color varies too much, but you check the level and see if it is missing. Also, pay attention to where the puddle forms in relation to the vehicle and engine.
Preventive maintenance after an engine replacement
Now, I won’t try to guess what led you to a situation where you had to replace the motor mainly because there are so many faulty and poorly designed motors from the factory. However, in most cases when people need a new engine, it is because the old one failed due to poor maintenance.
So, to prevent that from happening again, here’s what to do with the new engine from scratch. And also, make sure you get an owner’s manual and stick to all service intervals religiously from now on.
Motor oil
Changing the engine oil is the first thing you should do. That’s because it’s the most crucial element for long-term engine health. However, you also probably don’t know when it was last replaced. So check your owner’s manual to see what type of oil your engine takes, and replace it. After that, find the oil change intervals and stick to them.
Oil filter
The oil filter is just as important as the engine oil, and you should replace it with every oil change you have, that is, after installing a new engine. It is important to understand that an oil filter clogs over time. And then, even though the oil is fresh, it can’t go through the filter and get to the moving parts of the engine. That leads to essentially the same low oil pressure condition as if there was no oil in the engine. It goes without saying that under such circumstances, your engine will be destroyed in a matter of minutes.
Air filter
I can’t say that the air filter is as important as an oil filter or that it quickly causes irreparable damage. Still, it can cause the engine to run rough, lose power, stall, build up carbon deposits, and cause damage over time. Fortunately, the air filter is usually around $10 for any car, so there’s really no excuse for skipping this part.
Fuel filter
Technically, the fuel filter is part of the chassis and fuel system rather than the engine itself. However, it doesn’t hurt to replace it if you’re not sure when it was last done. A clogged filter can cause the engine to run poorly, stall, destroy the catalytic converter, etc. But if you know it doesn’t need to be replaced yet, it’s okay to leave it.
timing belt or chain
Depending on the engine, the timing belt or chain can destroy everything again. Now, if you have purchased an engine that you know the full service history and mileage for, it is okay to leave both if they are not yet due. However, if the engine has a timing belt and you are not sure, the best thing to do is to replace it along with the water pump and tensioner. After that, keep track of the mileage and the next service interval so that you can replace it on time.
On the other hand, if the engine has a timing chain, it will be much more expensive to replace. Also, timing chains often don’t have a service interval, so even if you have the service history, it won’t be much help. So what you need to do here is do an inspection. Specifically, check if the chain is loose or visibly worn, and check if the tensioner is working properly.
Also, the best way to inspect a timing chain is to get a shop manual or check forums to see how long the chain should be. That way, when you inspect, you’ll know exactly what to look for and how loose the chain may be.
Auxiliary Belts
A faulty auxiliary belt will not cause much trouble even if it breaks, but it will be very inconvenient. Also, the power steering pump will stop working, which can be extremely dangerous if it happens at the wrong time. Therefore, first do a visual inspection, and then check the clearance. But as good as they look, auxiliary belts are relatively cheap and easy to replace, so it doesn’t hurt to install a new one.
Water Pump
And lastly, be sure to inspect the water pump. That being said, the only thing you can check with a water pump without disassembling it is if the inner bearing is okay. Otherwise, to check anything else, you’d have to remove it, and that means buying new gaskets, too. Now, considering that a faulty water pump can also destroy an engine, it is best to replace it even if it is not especially cheap.
However, that is unless you know when it was last replaced and the mileage on the engine. But since, in most cases, that means trusting the seller, I again advise you to replace the water pump.
How long will a car last after engine replacement?
How long a car lasts after engine replacement depends on the engine. In the event that you have a new engine, it will likely last over 150,000 miles if you maintain it properly. However, there are few to no warranties with used engines, and your mileage and overall condition will greatly affect how long they last.
Is it worth replacing an engine?
Yes, most of the time, an engine is worth replacing. However, it is always about the relationship between cost and resale price. So if you can sell your car for €5,000, but the engine replacement costs €3,000, then it makes much more sense to sell it as-is. Still, that’s rarely the case with newer cars, where you can buy a used engine with low mileage, and even the cost of a new engine isn’t that close to what the car is worth.
How much does it cost to replace a complete engine?
Total engine replacement cost is typically between €3,000 and €5,000. However, it can be as low as €1,500 if you have an older car with a smaller engine. But for reference, a new Ford 2.0 EcoBoost engine costs €4,000 and you can expect to pay around 15 hours of work.
Can you trust a car with a replaced engine?
Yes, you can trust a car with a replaced engine as long as the engine is new. As for used engines, that largely depends on how trustworthy the seller is. But if the mileage is low and you came out of a wrecked car, it shouldn’t be much different from a new engine.
Is it better to replace an engine or buy a new car?
It is better to replace an engine if you can afford a new one or a low mileage one. That’s because you’re essentially taking your car back in time, and the new engine will last as long as a new car’s. If not, it’s a better idea to buy a new car.
What is the useful life of a car engine?
The typical life of a car engine before it needs a complete rebuild is around 200,000 miles. However, that is if the engine received regular maintenance and oil changes. Also, many engines can do much more than that, while those that are not properly maintained can fail at 100,000 miles or even sooner.
Conclusion
Ultimately, there are many things that you need to be aware of and replace along with the engine. And it’s important to remember that you won’t really know if the new engine is seated until you’ve driven around 1,000 miles. Still, the key things to check after replacing an engine are overheating, fluid loss and leaks, exhaust smoke, and warning lights.
And in case the engine is in good working order, preventive maintenance must be done, especially if it is a used engine. Some of them include a new timing belt, water pump, engine oil and oil filter, air filter, and fuel filter. And along with that, you can check the auxiliary belt and all the tensioners. Lastly, if the car has a timing chain, you don’t necessarily have to replace it, but a thorough inspection is required.
For more information, check out these other articles:
How long does it take to replace an engine?
Does replacing the engine reset the mileage on the odometer?
2023 Honda Civic Engine Replacement Cost
