What Causes Water to Enter a Diesel Engine?

[DeCourtney]

Here are the specific reasons for water entering the engine oil in a diesel engine: 1. Cylinder liner damage: Water in the diesel engine oil may be due to cracks in the cylinder liner, allowing coolant to seep directly into the engine oil pan through the cylinder wall. It could also be caused by aging of the cylinder liner sealing ring, in which case the seal should be inspected. 2. Engine water plug leakage: If the engine water plug is severely aged, it may leak. In this case, coolant will mix directly with the oil in the oil pan, so regular inspection of the water plug is necessary. 3. Radiator damage: Damage to the oil radiator tubes can also lead to water entering the engine oil.

[SanSadie]

I've experienced diesel engine water ingress before. Here are the summarized causes: The most common is rainwater or floodwater entering through the air intake, especially when driving through water during heavy rain. Design flaws in the exhaust system can also allow water to backflow into the engine. Additionally, cooling system leaks, such as aging water pump seals causing antifreeze to mix with engine oil, can lead to 'emulsification'. Once, my car's cylinder head gasket burned through, allowing coolant to directly leak into the combustion chamber. External factors include poorly sealed fuel tank caps and improper car washing introducing water. If water ingress is detected, don't start the engine - have it towed for repairs first. Otherwise, piston connecting rods may deform requiring major overhaul (I learned this the hard way, costing me over 10,000 yuan). Regular checks of air filters and drain valves, along with periodic cooling system maintenance can prevent problems.

[McAshley]

There are many sources of water ingress in diesel engines, and I recommend focusing on prevention. Parking the vehicle in low-lying areas during the rainy season can lead to water accumulation that may submerge the air intake. When driving through water, changes in exhaust pressure can cause water to be sucked into the cylinders. Cooling system failures are another major issue, such as cracks in the engine block or damage to the radiator, allowing liquids to intrude. Daily maintenance oversights, like dirty or clogged air filters blocking drainage channels, can prevent rainwater from draining promptly. During every maintenance check, I inspect the oil pan for signs of emulsification—when oil mixes with water, it turns into a white, foamy substance, immediately reducing engine power. The key is to avoid starting the engine if water ingress is suspected; instead, tow the vehicle to a repair shop to prevent engine failure. Develop good habits: avoid water puddles on rainy days and regularly replace sealing components.

[AngeloAnn]

Water entering a diesel engine can have various causes. External factors include wading through deep water or rainwater backflow; internal causes may involve cylinder gasket damage or poor sealing leading to coolant leakage. Design flaws in the air filter causing water accumulation that isn't drained promptly also pose risks. Once water enters, emulsified oil can clog fuel lines and damage cylinder blocks, necessitating immediate professional repair.