What to do when driving on flooded roads?
Experts recommend that when driving on a flooded road and the engine stalls, drivers should not restart the engine but should call for emergency assistance.
According to the National Center for Hydro-Meteorological Forecasting, due to the impact of storm No. 2, on July 23 and 24, the Northeast, Northwest and Hanoi regions will experience moderate rain, heavy rain and thunderstorms, with some areas experiencing very heavy rain. Heavy rain will cause flooding on some roads, making it difficult for vehicles to move and possibly leading to engine failure.
Automotive experts recommend that if a flooded road is unsafe, drivers should not drive through it but should choose another route. Avoid driving next to large vehicles or vehicles coming from the opposite direction because these vehicles can create waves that can easily cause water to enter the engine compartment. Drivers should also turn off the air conditioner and drive in low gear.
According to Mr. Ngo Duy Ngoc - a traffic rescue worker in Mai Dich area (Nam Tu Liem, Hanoi), if the car moves into a flooded road and the engine stalls, the driver should not try to restart it because it will lead to water hammer, the repair cost is very high. Therefore, if you want to move through a flooded road, the driver needs to be very careful, even with a high-chassis vehicle.
According to auto engineer Le Van Tach, when entering a flooded area without knowing the depth, drivers should drive slowly to avoid water suddenly entering the engine, causing water hammer, bending or breaking the connecting rod.
According to Mr. Tach, if the car is driven slowly and the water is deep, the engine will automatically stall. In that case, the driver must absolutely not start the engine but call for assistance. If the driver tries to restart the engine, the air intake system will continue to operate, the pistons will be pushed up very quickly by the crankshaft to continue the air compression process. However, the amount of water entering the combustion chamber will exert a huge force in return. These two forces will cause the connecting rod to deform.
"In mild cases, the connecting rod will be bent and the cylinder wall will be scratched. In severe cases, the connecting rod will break, leading to a puncture in the cylinder wall, destroying the engine and requiring huge repair costs. Vehicles entering flooded areas need to go to garages to check and clean the air filter, air intake, and air mixer to avoid water entering the combustion chamber and causing the vehicle to stall," engineer Le Van Tach advised.
Hydrolock is the phenomenon of water entering the cylinder combustion chamber through the air intake while the engine is running, causing the piston to be blocked and the fuel cannot burn in the combustion chamber, leading to engine failure.
Compared to gasoline engines, diesel engines are more susceptible to water hammer and more serious damage because diesel engines have higher compression ratios and smaller combustion chambers, so even a small amount of water entering the engine can cause water hammer.
