How to check for a blown head gasket

A head gasket is located between the engine block and the cylinder head. If you’re not a mechanic or car DIY-er, you might not know much about what this part of your car does. In short, its purpose is to seal in the internal combustion process and prevent coolant and oil from mixing together as they travel from the engine block to the cylinder head. Pretty important stuff!

Because the head gasket is exposed to hot and cold temperatures over time, it’s not uncommon for yours to develop leaks. Fortunately, there are telltale signs that point to problems with the head gasket.

White steam blowing out of the exhaust

It isn’t unusual to see a bit of smoke coming from the exhaust when you start your car first thing. There may be a problem, however, when you see visible white smoke accompanied by a sweet smell when your car is running at a normal temperature. This may be a sign that there is coolant in the exhaust as a result of a leaky head gasket.

Loss of coolant

Coolant leaks are another symptom of a problematic head gasket. If you notice that the coolant levels within your reservoir or radiator are low, first check for leaks on the outside of the engine, water pump, radiator and other cooling system components. If no leak can be found, it’s most likely that your gasket is blown.

The presence of combustion gases in the engine coolant

This is one of the most accurate ways to diagnose whether or not you have a blown gasket, but it can only be done when the engine is warm and the radiator cap is removed. Place a funnel where the radiator cap would be, start the engine, and then watch the coolant as it circulates. If you begin to see an overwhelming amount of bubbles, that indicates gasket failure. WARNING: Be extremely careful when doing this, as hot coolant may spray out of the radiator.

While these are some of the most common signs of a blown gasket, there are other things you need to keep an eye out for. If coolant is leaking from your exhaust or your engine is overheating, it’s best to take your car into a mechanic to check it out.

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While pinpointing these problems may be fairly simple, replacing a head gasket isn’t something that you can necessarily do yourself. The best way to keep a head gasket from failing is maintenance. Also keep an eye on the cooling system to make sure that your engine is working correctly. The failure to correct something minimal like this early on can end up costing you thousands of dollars in the long run.