How do know if you have a cracked block?

To determine if you have a cracked engine block, look for signs such as coolant leaking or mixing with oil, which may appear as a milky substance on the dipstick. Additionally, check for external coolant leaks or white smoke from the exhaust, indicating coolant burning in the combustion chamber. A compression test can also reveal inconsistencies in cylinder pressure, suggesting a possible crack. If you suspect a crack, it's best to consult a professional mechanic for a thorough inspection.