What Causes a Small Amount of Water to Enter the Engine?
3 Answers
Here are the specific reasons for a small amount of water entering the engine: 1. Damaged oil cooler: When the cooler pipes crack, water outside the cooler can seep into the oil cooler, causing water to mix with the oil. 2. Engine water plug leakage: After years of use, scale and corrosion can cause some water plugs to rust, allowing coolant to enter the oil passage from the water channel. 3. Damaged cylinder liner seal: The cylinder liner is in direct contact with the coolant. The seal at the lower part of the cylinder liner effectively prevents oil and coolant leakage. During use, the seal is subjected to certain pressures, and poor coolant quality can cause corrosion. After prolonged engine operation, the seal is prone to failure.
That day I drove my old car through a waterlogged section and didn't notice the depth. Water suddenly splashed into the engine's air intake. This is a common cause of water ingress, especially during heavy rain or in flood-prone areas. If the intake system isn't tightly sealed—for example, if there are gaps in the air filter box—rainwater can seep in bit by bit. Also, if you often park in low-lying areas, rising road water levels can allow water to infiltrate the engine bay, causing this issue. I remember catching it in time that time, avoiding major damage. I'd advise everyone to avoid deep water when driving, choose higher ground for parking, and regularly check the tightness of intake pipes and air filters to prevent small issues from turning into big troubles.
I found that slight engine water ingress is mostly related to the cooling system. For example, if the cylinder head gasket ages and cracks, coolant may leak into the cylinders, or if the oil seal in the oil circuit fails, moisture can seep in. These components are prone to wear over time, especially on bumpy roads which accelerates deterioration. Pay close attention to the temperature gauge and any unusual engine noises while driving daily. If any abnormalities are detected, pull over and inspect as soon as possible. Don't let minor issues accumulate, as water mixing with oil can lead to cylinder scoring or internal rusting, resulting in exorbitant repair costs. The key is to regularly replace the coolant and inspect the condition of oil seals.
