Engine Overhaul vs Engine Remanufacturing

engine in need of overhaul

What is an engine overhaul?

Cars are expensive and when you have engine trouble, repairs can be expensive. What above when the mechanic tells you that your car needs an engine overhaul? Well, let’s dive into that topic: 

Does smoke come billowing out of the tailpipe? Or is it constantly running hot? If your car has begun to sound ‘funny’ at an idle, when you accelerate, or when you turn the car off, it may need an engine overhaul.  

If a mechanic has suggested you need an engine overhaul without inspecting the engine and other major components, you should get a second opinion. No matter how experienced a mechanic claims to be, a reputable auto garage knows they need to look further before stating an engine overhaul is necessary. Or the mechanic may give you the option of having the engine remanufactured instead of an engine overhaul.

If you’re not a car person, you may be confused with some of the terminology, such as what is the difference between an engine overhaul vs engine remanufacturing? A remanufactured engine is using the blueprints and specifications from the manufacturer to remanufacture the engine back to its original condition when it came off the assembly line. It is the next closest thing of buying a crate engine from the factory. 

The process of an engine overhaul is when the mechanic takes care of any failure issues, like the smoke billowing from the tailpipe. Let’s talk a little bit more about the different levels of an engine overhaul: 

What does it mean to overhaul an engine?

An engine overhaul is when a mechanic takes the entire engine apart, cleans all the parts, replaces any damaged or worn parts, gaskets, or seals, and puts it all back together. This requires the engine be lifted out of the car so that every bolt, nut, and part is easily reached, and factory approved parts replace the existing parts. 

Some mechanics refer to an engine overhaul as “in-chassis’ rebuild. This is when they rebuild only the ‘top’ part of the engine, which doesn’t require pulling the engine out of the car. The replace components of the engine like the cylinder liners, pistons, and piston rings. 

The first engine overhaul we described is more extensive and is a major undertaking, and more expensive. Are there engine overhaul benefits? Definitely, take a look at three main benefits:  

  • Upgrades the Performance: The engine is restored to factory-like condition with any defects with the engine are fixed, damaged and worn parts are either repaired or replaced. This will give you better fuel efficiency and overall performance.
  • Extended the Lifespan: With an engine overhaul, your car has a renewed lifespan. 
  • Less Expensive Than New Engine: An engine overhaul is less expensive than buying a new engine, buy hundreds of dollars! 

As with all good things, there are some engine overhaul disadvantages too. Yes, the end result is effectively a new engine after all the new parts are installed, but possible issues: 

  • An engine overhaul can take a long time – it all depends on the availability of the parts. If they are available locally, the process will go faster. If the mechanic has to order them, it could add a week, maybe two, or longer. 
  • An engine overhaul can get expensive – again, depends on the availability of the parts and where the mechanic has to order the parts from. The bigger the engine, the more costly an engine overhaul can be. 

How do you know if you need an engine overhaul?

There are many conditions that could be telling you it is time to consider an engine overhaul. Here are the five main ones:

  • White smoke coming from the tail pipe: This is an indication that the engine is burning on the inside or burning oil as old timers would call it. This is wearing out the pistons and rings, affecting the engine’s overall performance. 
  • Excessive fuel usage: When the start plugs are worn out, they aren’t working adequately and that affects the fuel usage of your car. 
  • Power reduced: When a car recognizes particular electronic issues, the motor control module begins to constrain the gear range, motor power, and speed. Several things can cause this from a bad battery to an actuator or sensor being out of order. When this happens, the transmission, the voltage, and everything that runs the car isn’t getting clear communication to power the car. 
  • A knocking noise as accelerating: When you accelerate, an unusual knocking noise could be the air and fuel mixture is wrong because of a clogged filter or fuel screen.
  • Damaged valves: When a valve fails to close adequately, the combustion fuels past the valve seat and the valve head overheats. 

Is it cheaper to rebuild or replace an engine?

Well, it is most of the time. As we mentioned above, it can get expensive buying parts for an engine overhaul. It depends on what size and type of engine and where the mechanic has to get the parts.  

You can purchase an engine that has been rebuilt already versus buying a new engine, and have it swapped with your car’s existing engine. Or you can have your mechanic purchase a crate engine direct from the manufacturer. Those are more expensive options than the typical engine overhaul. 

Then, there is the option of buying a new car if the engine in your current car quits. With that scenario, consider the car payment and car insurance, then an engine overhaul would be the cheaper option.   

Engine with new air flow

How long does an engine overhaul take?

This can depend on who is doing the engine overhaul and how detailed the job will be. A brief idea of the time it takes for a complete overhaul, which includes new bearings, rings, sleeves, valves, sleeves, and having the heads milled: 

  • The average garage shop:  4 days if they have all the parts easily accessible to 2 months if they need to order parts.  
  • A dedicated garage shop:  3 days if all the parts are available up to 1 month if they have to order any parts. 
  • A shade tree mechanic: Anywhere between three weeks to three years, depending on parts accessible and the time they have to work on the engine overhaul (if they have a full-time job and family activities. 

Is overhauling an engine good? If done properly and all damaged and worn parts are replaced, then yes, an engine overhaul is a good thing. It gets your car an extension on its lifespan, it keeps another ‘clunker’ out of the wrecking yard which helps the carbon footprint, and you’ll have an almost new-like car under the hood. Call 770-428-6440 today for engine service.