Experience in handling flooded cars

A good rule of thumb for drivers is to never force the engine to restart when the car stalls to avoid bending, breaking, or puncturing the cylinder wall.

Water not only affects the electrical system, dirty the interior but more seriously, it can damage the engine when it enters the combustion chamber. This causes water compression, also known as hydrostatic shock.

Engines, electrical systems, and engine oil are easily damaged when cars drive through flooded areas.

Below are the parts most easily affected when a car is flooded and basic handling:

Engine

The driver must not attempt to restart the vehicle, turn off the electrical system and, if possible, push the vehicle to a higher ground with an inclined angle. This will both prevent water from entering the combustion chamber through the air intake and allow water to escape through the exhaust pipe.

GCall a rescue team to check the extent of water ingress into the engine. If the problem is minor, the car can be slowly driven back to the garage for further inspection when the water level on the road allows. In more serious cases, the car will need to be transported or towed back to the garage by a specialized vehicle.

The owner of a Mercedes E-Class forced the car to start after it stalled due to water bending the connecting rod in the engine.

Trying to restart the engine will only cause further damage. The incompressible nature of water causes the connecting rods in the combustion chamber to bend due to the reciprocating action of the piston.

More dangerous is that forcing the car to start many times can cause the connecting rod to bend, break, or puncture the cylinder wall (break the engine block). The engine must therefore be repaired or replaced at high cost depending on the type of car.

The connecting rod broke, puncturing the cylinder wall in the car engine.

According to auto technicians, even when the car is in the garage, starting the engine must be done carefully. First, turn the engine by hand to check if the engine is jammed by foreign objects. Then continue to measure the engine compression pressure with a specialized tool.

If the compression pressure is still sufficient, it means that water has not entered the combustion chamber and the engine is still good. At this point, the vehicle can be restarted, but do not forget to check other parts for repair if there are signs of damage.

If the engine compression pressure is not enough, it means the engine is damaged. Disassemble the engine to check the internal parts such as cylinders, pistons, connecting rods, crankshaft. Depending on the severity, repair or replace.

Electrical system

Similar to the engine, the electrical system is also sensitive to water. Short circuits and damage to the vehicle's control system occur when water penetrates from the undercarriage to the floor. This leads to errors in parts or many functions of the car may malfunction. The deeper and longer the vehicle is submerged in water, the more likely the electrical system is to be damaged.

Typically, the electrical systems of flooded cars require detailed computer-assisted inspection before repairs can be made. The connectors are dried and sprayed with specialized chemicals to prevent oxidation.

Lubricants

When driving through flooded areas or deep water, the first thing to do after turning off the engine is to check the engine oil. When the oil turns milky white due to mixing with water, you need to drain all the old oil and replace it with new one. Engine oil and transmission oil are separate.

Unlike motorbikes, cars with automatic and manual transmissions use oils of different viscosity. Depending on the type of vehicle or manufacturer with its own technical standards, using oil for cars needs to be considered and performed by reputable garages.

According to VNE