I recently posted on this forum that I had a problem of loss of coolant, there wasn´t any leaks and the radiator cap seemed to have been working properly. Coolant expansion tank boiling, many people pointed that my problem could be related to my head gasket. Yesterday my car lost compression between two cylinders, the number 1 and 2, my mechanic took the cylinder head apart and saw that the head gasket was burnt between two cylinders. Before bringing the car to my mechanic I checked the cooling system to see if combustion gases were getting into the cooling system. I saw bubbles the first time I started the engine but after that there wasn´t any bubbles. The car was blowing some white and blue smoke on the tailpipe, and coolant loss was very slow like 300 cc every 3 days. I didn´t saw any condensation on the oil filler cap nor in the oil dipstick. My question is: Should I change my oil even when there aren´t any signs of coolant getting into the lubrication system?