Buying a Car With a Remanufactured Engine
When an engine fails, it is often the case that just one specific part has failed; but it is so expensive in labor costs alone to take the engine apart that it makes sense to replace all the moving parts rather than just the one failed part.
In a rebuilt engine, a mechanic will tear down the entire block. He may replace all the moving parts or only the ones that are worn out.
But most experts advise against such a job, unless the engine is relatively new and you know that it needs only a few specific parts replaced.
If you have a generally worn-out engine or an engine that has suffered major damage from loss of oil, it almost always makes more sense to buy a fully remanufactured engine. These remanufactured engines are torn down in small factories, where an entire set of crankshaft bearings, piston rings, seals and gaskets, among much else, is installed.
If properly done, a remanufactured engine should be as good as a new engine and it should carry a warranty for a year. And generally, it should be cheaper than a fully rebuilt engine.
But you need to find out exactly who is doing the rebuilding. There are hundreds of companies that remanufacture engines, so the trick is to pick one with a good reputation that has been in business for a long time. You might check to see if a particular company is a member of the Automotive Engine Rebuilders Assn., a trade group that represents the better companies in the industry.