How to Diagnose a Blown Cylinder Head Gasket
- 1). Start your vehicle and allow it to run until it is fully warmed up. At this point, observe the exhaust gases coming from the exhaust pipe. A blown head gasket will allow radiator coolant into the engine combustion chambers. The gases will be burned up and come out as white steam. If you see a white exhaust, smell it. If it smells "sweet," the chances are that you have a blown head gasket.
- 2). Check your radiator fluid when the engine is cold. If you notice that the fluid level is never full no matter how much you add coolant to it, you either have a leak in the system or the head gasket is blown. A way to confirm this is to notice the color of the coolant. If it is brownish, much like the color of chocolate milk, and you have been losing fluid, it is most likely a blown head gasket.
- 3). Attach a combustion leak tester to the neck of your radiator, where the filler cap resides. Using the supplied rubber bulb, pump in some of the blue test liquid supplied, and allow it to bubble through the coolant. If the coolant suddenly turns yellow, that is a sign that exhaust gases are present in the coolant, and the only way they can get there is from a blown head gasket.
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