What happens if water enters the engine and it is started?
3 Answers
It can cause the piston to seize, and in severe cases, the connecting rod may bend. Below is the relevant information: 1. Engine: An engine (Engine) is a machine that can convert other forms of energy into mechanical energy, including internal combustion engines (reciprocating piston engines), external combustion engines (Stirling engines, steam engines, etc.), jet engines, electric motors, etc. Internal combustion engines typically convert chemical energy into mechanical energy. 2. Connecting Rod: It connects the piston and the crankshaft, transmitting the forces acting on the piston to the crankshaft and converting the reciprocating motion of the piston into the rotational motion of the crankshaft.
I've seen this too often at the repair shop. Starting the engine after water ingress is simply disastrous. Just the other day, a customer's SUV forced its way through deep water during a heavy rainstorm. After stalling, they stubbornly tried to start it again, resulting in a bent connecting rod. That's because water in the cylinders simply can't be compressed! When the piston moves upward, it's a direct collision – at the very least, you're looking at dismantling the engine to replace pistons and connecting rods, and in severe cases, even the cylinder block can be punctured. The real kicker is that modern cars come with ECU computers; once the circuit boards get soaked, they're fried, and the repair bill could easily buy you a used car. Mechanics dread these cases the most – opening up the engine to find a mix of mud and engine oil just makes them shake their heads. If you ever stall in floodwater, the smartest move is to calmly call for a tow truck.
Last week, my friend's car got flooded, and in a panic, he tried to start it—resulting in the engine being completely destroyed. Simply put, water entered the cylinders, and when he tried to start the engine, the pistons moved upward but were blocked by the water—like trying to push against a solid wall. Normally, pistons can move up and down smoothly when compressing air, but water is nearly incompressible. This force can bend or even snap the metal connecting rods attached to the pistons. If the deformed rods continue to operate, the broken metal fragments can wreak havoc inside the entire engine. Not to mention, water conducts electricity and can short-circuit the electrical system. My friend ended up spending 40,000 just to repair the engine, and the insurance didn’t even cover it all. Remember: if your car is flooded, never try to start it!
