Under normal operating conditions, bearing lubricating oil should be changed at least once every six months. During operation, the first oil change should be performed after approximately 200 hours. The second oil change should be carried out between 1 and 2 months. Thereafter, inspect the lubricating oil weekly. If the oil has not deteriorated, the oil change interval may be extended to once every 2 to 4 months. When changing the oil, use only the specified grade of lubricating oil (as indicated on the general assembly drawing). Completely drain the old oil from the tank and clean it thoroughly before refilling with new oil.