how to know if cylinder head gasket is bad | WTA Guide

How to Know if Your Cylinder Head Gasket is Bad - WTA

Diagnosing a blown cylinder head gasket can be tricky, but understanding the common symptoms saves time and prevents further engine damage. This article outlines key indicators to help you quickly and accurately assess the condition of your cylinder head gasket.

Visual Inspection: Looking for Leaks and Damage

Start with a visual inspection. Look for external coolant leaks around the cylinder head gasket area. Evidence of coolant seeping from under the head, or oil contamination around the gasket, is a strong indicator of a failing cylinder head gasket. Check for any signs of discoloration or damage to the gasket itself.

Pressure Testing: A More Precise Diagnosis

Visual inspection isn't always conclusive. Pressure testing the cooling system and the cylinders provides a more precise diagnosis. A pressure test can reveal leaks not visible to the naked eye, confirming a faulty cylinder head gasket. Low compression in one or more cylinders can also point to a leak past the gasket.

Analyzing Coolant and Oil: Subtle Clues

Internal leaks often manifest as contamination. Check your coolant for signs of oil contamination (milky appearance). Similarly, check your engine oil for signs of coolant (a milky or foamy consistency). These are strong indicators of a compromised cylinder head gasket, allowing mixing of oil and coolant.

Exhaust Gas Analysis: Checking for Combustion Leaks

A cylinder head gasket failure can allow combustion gases to escape into the coolant system. Testing the coolant for the presence of combustion gases using a specialized kit is a conclusive method to determine if a head gasket is compromised. Higher-than-normal exhaust gas levels in the coolant confirms a leak.

Other Symptoms to Watch Out For

While the above are the most definitive signs, other less obvious symptoms may indicate a failing cylinder head gasket. These can include overheating, loss of coolant without visible leaks, and white smoke from the exhaust. These, however, are not exclusive to a bad head gasket and could indicate other problems.