How to Clean the Engine When Engine Oil Gets Mixed with Water?
3 Answers
If the engine only has mixed water vapor, simple treatment is sufficient. Just clean the water vapor from the air filter, throttle valve, and cylinders. If the engine has taken in a significant amount of water but can still operate normally, it is necessary to replace the engine oil and clean the related engine components. If a large amount of water has entered the engine but the car has not been started, reassemble it and replace the engine oil. If the engine has taken in a large amount of water and cannot operate after starting, the cylinders, connecting rods, pistons, etc., may have deformed, requiring replacement of the entire engine.
I was really scared last time when water got into my engine oil, so I immediately stopped to check and found the oil had emulsified, which is a sign of water contamination. When cleaning it out, make sure to completely drain the contaminated oil and avoid starting the engine directly to prevent further wear. I learned to flush the inside with flushing oil or kerosene: pour it in, start the engine, and let it idle for three to five minutes to circulate and remove the water, then drain the flushing fluid. Repeat this twice until the drained oil is clear, then finally refill with fresh oil and replace the filter. The source of water ingress could be from a cracked cylinder head gasket or a flooding incident, like rainwater entering the engine bay. Handling it yourself can save some money, but be careful—if flushing isn’t thorough, residual water can corrode parts. It’s best to take it to a repair shop to check if the seals are intact. Regularly check the oil color to prevent this issue, and act promptly if water is detected to protect the engine’s lifespan.
In my line of work as a car mechanic, oil contamination with water is a common issue that requires prompt action to avoid engine overhaul. The first step is diagnosing the source of water ingress: a blown head gasket, coolant leakage, or external water intrusion. After draining all contaminated oil, pour a specialized flushing agent mixed with kerosene into the engine, then run it for a few minutes to thoroughly clean internal components. Drain the flushing fluid, replace with fresh oil and filter, and test the engine for smooth operation. Neglecting cleanup increases the risk of internal oxidation, leading to bearing wear or worse failures. I recommend having a professional shop inspect and fix the root cause, as post-contamination sealing components may need replacement to prevent recurrence. Regular maintenance checks on oil condition enable early prevention, ensuring safety and cost savings through timely intervention.
