Just curious as to how you determined that you have water in your oil. Was it discovered during an oil chance or when you were checking the oil level? A little water accumulation ( a few drops from condensation) around the fill cap is not uncommon but water actually mixed into your oil is typically an indication of a gasket leak. Its possible that rain water could enter the crankcase via the fill cap IF it does not properly seal and you store the 500 outdoors in the elements. I'd also take a look at your coolant; the presence of oil or carbon deposits would confirm gasket issues. Is your coolant low?04 Polaris Sportsman 500 HO. Is this a common problem? What should I look for? Could this be a head gasket failure?
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