When you have a failed gasket, it will allow combustible gases to enter your cooling system. This will then manifest itself as bubbles of air that can be seen in your radiator or expansion tank. Remember to take extra precaution while doing this test because the coolant could erupt swiftly from the radiator. That’s the kind of exhaust gas you don’t want to be near in.

Most car owners will end with this test once they see that their filler cap has that gooey liquid. However, those who don’t detect this shouldn’t stop there. This test is not always reliable when detecting a head gasket. So it’s best to move on to other tests until you’ve exhausted all options. 2. The Spark Plug Test There are few problems more notorious than a blown head gasket. Not only can they be expensive and time-consuming to replace, but they’re also notorious for giving out. Before starting your test, remember, radiator caps are pressurized, and when these caps are removed when the radiator is hot, hot coolant may shoot out and burn you. Make sure your vehicle is well-cooled off before performing your test. So you’ve gone through the other tests and you see no coffee-colored engine oil and no external leaks. Surely you don’t have a blown gasket, right? Wrong. There are 4 things around a head gasket - combustion chambers (cylinders), oilways, coolant-ways and the outside air. They can fail between any two (or more) of these, and each has different symptoms.You’ll notice a drop in compression in the affected combustion chamber if you have a blown head gasket. That’s because the cylinder can never fully seal, and the excess pressure will escape. If you look at your exhaust and there’s far more smoke than usual, that might mean you have a blown head gasket. However, there are a few things you need to be aware of when diagnosing excess exhaust. If you're looking to complete DIY work on your garage or home, it's always important to wear the correct workshop clothing to protect yourself from harm. From workshop gloves to boots, we have what you need to stay safe. Loss of engine power – you might start noticing problems while driving before anything else. Pressure in the combustion chamber will decrease, and so will your engine power. There’s also a higher chance of overheating, which can cause more damage to your engine. The same applies if your motor oil and coolant leak into one another and stop lubricating properly.

This change of mind return policy is in addition to, and does not affect your rights under the Australian Consumer Law including any rights you may have in respect of faulty items. To return faulty items see our Returning Faulty Items policy. First, as the temperature drops outside, you can expect more exhaust than during warmer weather. This is entirely normal and doesn’t indicate a blown head gasket. The most common cause of a blown head is overheating which can cause damage, but pre-ignition issues can also lead to leaks if the fuel is combusted at the wrong time. Your coolant is a sealed system, which means that what you put in your system should stay there. And while the levels can fluctuate slightly due to differences in temperature and pressure, they should stay the same for the most part. Visual Inspection: coolant leaking into a cylinder will power wash the carbon off the cylinder head which can be seen and evaluated with an endoscope through a spark plug port as demonstrated here. The crankshaft may need to be rotated to line up the cylinder head to the proper focal length of the camera to put the surfaces of interest into focus.While most people are aware that a blown head gasket can send fluids to other parts of your engine, it’s less well-known that blown head gaskets can lead to external leaks. Longer crank engine time is another sign of a failed gasket. Even worse, other cars that are suffering from this problem won’t even start. Testing for a Blown Head Gasket Since cylinders are tested on an individual basis one may need to test all cylinders before the failed one is discovered. Examples Do this right by pressuring the cooling system once you’ve removed the spark plugs. Crank up the engine while you conduct your inspection. If there is coolant in one or more of your spark plug holes that starts spraying out, then you are dealing with a blown head gasket. 3. The Bubbles Test

It’s all about where the leak is. If it’s towards the outside of the head gasket, you’ll have fluid dripping down the outside of your engine instead of going into different passages. It’s not recommended to drive with a blown head gasket as pressure in the combustion chamber reduces and the engine will lose a great deal of power.After taking about 1/2 litre of coolant out I got a clear head gasket failure indication, later confirmed by a compression test showing zero on 2 adjacent cylinders. These leakages tend to occur due to damage to the gasket – usually called a “blown gasket”. What are the signs of a blown head gasket? White exhaust smoke – evaporating coolant that’s leaked into the combustion chamber may cause visible white exhaust smoke. If smoke comes out of the coolant reservoir when the coolant cap is off, it can also mean that compression is going into the coolant system. This can be tested with an exhaust tester also. 6. Run a Compression Test Moreover, if the seals start to give out, you’re going to run into a litany of problems that can lead to further engine damage. It might seem like a simple component, but it has a critical job. How To Test Your Head Gasket