car oil is fine, we use it in work in our mowers in the parks, just drain off the old oil first, if you turn the mower over and look around were the blades are, you will see a nut, or alankey bolt, open it and drain off the old oil, put it back on tight, refill the oil back up to the marker on the cap, just make sure you have any oil in it when your running it, good time to change the sparkplug for a new one of the same lenth and power, and take out the oil filter and wash it and put it back in,
j, April 2012
