Oil and coolant cross contamination: If there is a crack in the engine, oil and coolant can leak into each other. This can cause a milky or foamy appearance to the oil, or it can cause the coolant to become thick and oily.
Smoke from the exhaust: A cracked engine can also cause white smoke to come from the exhaust. This smoke is usually caused by coolant leaking into the cylinders and burning off.
Engine overheating. If the crack is causing coolant to leak out of the engine, it can lead to low coolant levels and engine overheating.
Knocking or tapping sounds from the engine. Cracks can cause the engine to make loud noises that can be heard, especially when the engine is cold or when it is under a lot of stress.
If you are experiencing any of these symptoms, it is important to have your engine checked out by a mechanic to diagnose the problem and determine if the engine is cracked or if it is a blown head gasket.
