Water in Oil Emergency — The One Thing You Must Not Do
If you suspect water in your engine oil, the single most important action is not starting the engine. Here's why, and what to do instead.
The Single Most Important Rule
If you see milky oil on your dipstick, notice your coolant level has dropped, see white smoke from your exhaust, or have any reason to suspect water or coolant has entered your engine oil — do not start the engine. Do not turn the key. Do not move the vehicle under its own power. Call EEK Mechanical on 0800 769 000.
Why Starting Makes It So Much Worse
When an engine runs with water or coolant in the oil, several things happen simultaneously: the oil pump circulates the contaminated emulsion through all bearing surfaces; the bearings — which rely on a pressurised oil film — lose that film protection and begin metal-to-metal contact; heat generated by friction causes further degradation; and if water has reached a cylinder, hydrolocking causes instant catastrophic mechanical failure. Five minutes of running on contaminated oil can produce damage that takes significant cost to repair. Five seconds with water in a cylinder produces damage that cannot be repaired — only replaced.
What to Do Instead
Keep the engine off. Note what you have observed. Take photos of the dipstick and oil filler cap if safe to do so. Call 0800 769 000. wait for the tow truck. Do not allow breakdown services to start or move the vehicle unless they have been briefed on the situation and confirmed the engine is safe to run (it typically is not).
Related Articles
Coolant Mixing with Engine Oil: What You Need to Know
Coolant mixing with engine oil can cause severe engine damage. Learn how it happens and what to do next.
Post-Flood Car Checks: Oil Systems & Professional Inspections
Learn how to check your used car's oil system after flood damage and why professional inspections are crucial. Get expert advice on avoiding hidden risks.
What Causes Water in Engine Oil? A New Zealand Guide
Water in engine oil is one of the most destructive mechanical events a vehicle can experience. This guide covers the five most common causes and what to do in New Zealand.