Engine rebuild service vs Engine replacement

engine rebuild service

The question always comes up when a catastrophic car engine failure happens: should you replace your engine or call an engine rebuild service? When replacing an engine, you can get lucky and find a salvage yard unit in good condition or go with a remanufactured unit. There are a few things you must consider before deciding whether to replace or rebuild it, such as:

How do you know your engine is busted

Many symptoms let you know your engine is a goner. Constant misfires, engine burning oil, which can be easily identified by a vast cloud of white smoke coming from your exhaust pipe, persistent oil leaks, and an irregular knocking sound coming from your engine that was definitely not there before.

Even if your car’s engine gets one or more of those symptoms, you still need a professional to diagnose its condition accurately. Especially with modern engines, a faulty sensor might make your engine behave in all sorts of strange ways. It also could be a minor problem, like a timing issue or a faulty spark plug that leaves the piston without explosions, throwing the engine off balance. So remember to get a proper diagnosis.

Short block engine replacement

If your engine got damaged or cracked, that doesn’t mean every part is useless. Some times it’s sufficient to do what is called a “short block.” A short block consists of replacing just the engine block and rotating assembly – crank, rods, pistons, rings, etc. You take the missing, still functional parts from the damaged engine and move them to the new one.

Long block engine replacement

Unlike the short block, this process also includes the cylinder heads and the valve train. Basically, replacing the whole engine and connecting it to the fuel intake and exhaust system. Many times you’ll have to change the belts and hoses as well if damaged during the breakdown of the previous engine.

Skilled craftsmanship availability

Most people don’t know about the strict tolerances in place when assembling an engine. You absolutely have to use a torque wrench to ensure that everything is torqued to specification. Not only that, but in some cases, you also have to torque everything in the right order, starting from the center so that the covers don’t end up tilted and resulting in the loss of compression.

Some mediocre mechanics will just tell you to replace the rings, and you should get no more problems. Still, the cylinder’s finishing must be exact for it to work correctly, or the piston will bounce inside the cylinder creating an awful racket and damaging your engine even further.

If it’s the first time you’ve had an engine rebuilt, the cylinders can be machined to get them to a slightly larger diameter, and you’ll have to use larger pistons. That way, you can get an exact finish, and using the correct size pistons and ring sets, you can ensure no loss in pressure and compression.

Many things can go wrong with an engine rebuild, which may damage your engine beyond repair. Remember to send your engine to certified skilled professionals only.

Availability and pricing

Replacing is almost always going to be more cost-effective than rebuilding. That is unless you want to maintain your car in stock condition, such as in classic cars. Or perhaps the engine you are trying to rebuild is hard to find for your specific model, maybe its an imported car or an old model.

You can easily buy a reconditioned engine which usually costs around two thousand dollars, and you can find them with a two or three-year warranty. In addition, you’ll have to pay around a thousand dollars for labor to have it installed in your car.

You can also find new engines and performance engines from three thousand dollars all the way up to eight thousand or more depending on what you are looking for.

If you get your engine to a rebuild service, it can cost you from two to four thousand dollars, including labor and parts. It is also going to be challenging to find a rebuild service with a two or three year warranty, so you’ll be taking a higher risk. Since we already mentioned that many things could go wrong with an engine rebuild unless done by seasoned professionals, this option should probably be your last resort.

When is an engine rebuild service not an option

Sometimes rebuilding the engine just isn’t an option. Here are a few instances of engines that you can’t rebuild:

  • If the engine block itself is cracked, rebuilding it will never be a safe option.
  • If it has a hole on the side
  • In the case that it has been rebuilt too many times before and it doesn’t have enough material to machine the cylinders
  • Or if rebuild kits can’t be found for that specific model because its too old or too rare

Many reasons determine when an engine is not safe or cost-effective enough to rebuild. Just remember that an engine has thousands of controlled explosions going on inside of it every minute. They are precise pieces of machinery, so always listen to the manufacturer guidelines and never “eyeball it.”

You can always sell it.

Many people don’t have the time or the will to deal with these issues. There are many sites on-line that will buy your car with a blown engine as is. That is by far the least cost-effective solution, but it’s undoubtedly the quickest way to get you back on the road. You can be driving again in no time at all.


In most cases, it’s going to be more cost-effective to simply replace the engine. However, there are many legitimate reasons to rebuild an engine as well.

If you need to find skilled mechanics to help you either replace or rebuild your car’s engine, you can find them here. We are more than happy to help you connect with high-quality professionals to ensure the correct functioning of your vehicle for years to come.