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NL Do you find oil in the coolant, for example on the surface of the coolant in the expansion tank? Not good. This indicates a leak in the engine, or more precisely in the head gasket or cylinder head. All information on this problem and an inexpensive solution that you can apply yourself without a workshop can be found in the last section on this page.
Table of contents
Oil in the cooling water
Have you discovered traces of oil in your car's coolant? The mixing of Engine oil and cooling water is a clear sign of a crack in the cylinder head or cylinder head gasket on the cooling water side. A cracked cylinder head or a leaking head gasket will cause an overflow between the channels of the cooling system and the oil circuit. The fine cooling water and engine oil channels are distributed over the entire engine crankcase, ensuring smooth operation.
If hairline cracks occur between these channels, the fluid will flow in one direction or the other and the two fluids will mix. This can have fatal consequences and lead to total engine failure within a very short time, as the moving parts in the engine are neither sufficiently lubricated nor cooled. Fortunately, you can avoid unpleasant surprises by regularly removing the radiator cap or expansion tank cap and checking not only the coolant level, but also the color and consistency of the coolant.
Engine oil in the cooling system - signs of a defective head gasket
Cooling water in the engine oil
Just as engine oil can get into the cooling circuit via a crack in the cylinder head, coolant and water can also get into the engine oil. This happens when the hairline crack in the engine has become so large that coolant enters the oil circuit. Hairline cracks are rarely detected at an early stage due to the lack of recognizable symptoms. Coolant or coolant water in the engine oil can be recognized as a creamy substance on the dipstick or on the inside of the oil cap.
Cooling water in the engine oil - recognizable by yellowish slime on the oil dipstick and light brown discolored oil.
Simple and cost-effective head gasket repair
Simply pour the correct amount into the radiator or expansion tank, allow the engine to warm up, cool down and continue driving as usual.
Steel Seal® today.
Checklist for a crack in the cylinder head or on the head gasket
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- Check both the engine oil and the coolant. If you notice any discoloration that seems unusual, you have found an initial indication of the cause of the problem.
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- Check the oil and coolant levels regularly. Do not continue driving if either is below the specified minimum mark, otherwise there is a risk of even greater damage to the engine due to overheating.
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- Of course, you should also look out for warning lights illuminating on the dashboard in the car, as well as signs of unusual driving behavior in your vehicle.
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- A sudden, heavy loss of cooling water may indicate a burst cooling water hose, a leaking water pump or a defective radiator.
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- Stop the engine immediately if white smoke comes out of the exhaust.
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- Check the correct mixture of coolant and antifreeze in the radiator or expansion tank regularly, especially in winter.
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- Always pay attention to the engine temperature display while driving and switch it off immediately if the engine overheats. On Overheating motor may be due to a defective cylinder head gasket or a cracked cylinder head.
