Many vehicles have been damaged by the recent floods caused by Cyclone Ditwah in Sri Lanka. Fixing a flood-damaged vehicle is not something you can do in a hurry. It must be done step by step, with a lot of care.
At ikman, we decided to bring you a comprehensive guide on the most important things needed to revive a vehicle caught in a flood. Here, we are going to discuss the dos and don’ts regarding a flood-damaged vehicle. The first and most critical step is to avoid starting the engine. Okay, let’s discuss this in detail now.
Is it suitable to start a vehicle caught in a flood?
Just hearing about a vehicle caught in a flood and thinking “the water might have drained, let’s see if it starts” is something you should absolutely not do. It is important to understand the scientific and mechanical reasons behind this.
The danger of hydro-lock
The biggest risk to a flood-damaged engine is something called hydro-lock. In simple terms, this happens when water enters the engine’s combustion chambers. When you start a normal engine, the piston moves up and compresses a mix of air and fuel. Air and fuel can be compressed without a problem. But water cannot be compressed.
If there is water inside the combustion chambers and you try to start the engine, the piston still moves up.
Then it hits the water, which does not compress. This creates extreme pressure inside the engine.
Because of this pressure, the piston connecting rods – which are very strong parts – can bend or even break. That means serious internal engine damage. In many cases, you may have to replace the entire engine or spend a very high amount on repairs.
The good news is that you can avoid this completely. By simply not starting or operating the engine after a flood, you can prevent hydro-lock 100%. Modern vehicles rely heavily on electrical systems. Floodwater, especially dirty water, can conduct electricity very easily.
In a situation like this, disconnecting the battery is the safest first step. If the battery stays connected, electricity can flow through the water inside the vehicle. This can cause short circuits, which may burn wires, blow fuses, and even damage the ECU (Engine Control Unit) and other control modules.
The ECU is basically the brain of your vehicle, so damage here can be very costly.
You can reduce this risk by quickly disconnecting the negative (-) terminal of the battery. This cuts off electrical power to the vehicle. If possible, removing the battery completely is even better.
Check out our other blogs for more insights!