This is #2 from a series of 6 very useful, and low cost, motor oil tests that you can perform without even a simple chemistry set. nnEven though any individual can end up with water in their motor oil, it is more commonly an issue for those vehicle owners that make primarily low mileage trips with their vehicle, drive very infrequently and/or live in a humid climate or one with extreme and changes in temperature. If you are one of these individuals, it would be wise to perform the crackle test, which is an invaluable tool for determining whether condensation has caused a build-up of water in your oil.nnWhy should you care about water in your oil? Because H2O in your engine oil causes build-up of acid, which causes corrosion. Corrosion causes pitting, and pitting is definitely BAD for your vehicle’s engine. Even a high TBN extended change interval synthetic oil like AMSOIL can eventually be overcome by water/acid build-up.So, it is really quite important to know if you’re getting water build-up in your oil BEFORE the acid fighting additives in your oil are used up. THAT is why we do the crackle test.nnHowever, if performing the blotter spot test before the crackle test shows that you have fuel in your engine oil, performing the crackle test will likely be of little use, since the fuel in your oil will skew your results. This is why the blotter spot test (business card test) is most often performed BEFORE the crackle test. If you’ve got fuel in your oil, you may already need to change out your oil, and the results of the crackle test will not be clear anyway.nnPerforming the test is simple: place a small quantity of oil onto a hotplate of some type (just a few drops). Set the hotplate to a temperature greater than 212 degrees F (the boiling point of water). Since motor oil won’t typically be volatile till 350 degrees F or higher, setting the temp of the hotplate anywhere between 250 and 300 should work well.nnListen for the sound of the crackle. At this temperature, you should soon hear the crackling of the boiling water, IF you’ve got water in your engine oil. The more oil you put on the plate, the longer it will take the water to boil, so keep the amount to a minimum.nnOf course, the crackle test is not a very informative test, and it won’t provide any detail as to the AMOUNT of water in your oil, as a professional oil analysis will, but, it can provide you with some helpful, free info.