Is it possible to replace the engine of a water-damaged car?
2 Answers
After a car has been submerged in water, replacing the engine is an option. However, for economic considerations, it's advisable to first have the vehicle inspected at a repair shop before proceeding with further actions. Precautions for engine replacement: Specialized and standard tools must be used for engine disassembly and assembly. Rough handling is strictly prohibited to avoid damaging engine components. Engine disassembly and assembly should only be performed when the engine block is completely cooled; otherwise, it may lead to deformation of certain parts and reduce the quality of engine reassembly. To prevent deformation of components during engine disassembly and assembly, especially for major parts such as the cylinder head and crankcase, the loosening and tightening of screws or nuts should be done symmetrically and evenly. It is strictly forbidden to loosen or tighten screws or nuts on one side before doing the same on the other side. Components or assemblies should be marked during disassembly to avoid confusion during reassembly. Examples include valves, pistons, the meshing position of the engine timing gears, and all connected wiring terminals. Other components should be reassembled according to the original motorcycle repair manual. Method for engine replacement: Apply for engine modification at the license and certificate management office, undergo an inspection, and proceed with the modification only after passing the inspection. Unauthorized engine replacement is not allowed. As the power output device, the engine must be compatible with other parts of the car, such as the transmission system and cooling system.
Technically, replacing the engine in a flood-damaged car is possible, but I must say it's not just a simple engine swap. A flooded engine may have ingested sediment or suffered severe corrosion. While a new engine can address power issues, the critical point is to inspect other components, such as wiring harnesses and sensors, which are prone to short circuits or rust after water exposure. If these aren't addressed, the car might suddenly stall or even catch fire while driving. Additionally, the chassis and interior are major concerns—if the flooding was severe, moldy and foul-smelling carpets or rusted chassis components can compromise structural safety, posing even deadlier risks. My advice is to first have a professional shop disassemble the car to assess the overall damage. If it's only minor flooding and the engine is the main issue, replacing it might be viable. Otherwise, the car's value may not justify the repairs, and scrapping it for a new one would be wiser—safety should always come first. Cost-wise, the engine itself isn't cheap, and when you factor in labor and other parts, you're looking at tens of thousands of yuan. It's worth considering whether it's truly worth the investment.
