I was given a rescue mower by a friend and it runs well after cleaning some ethanol fungus out of the carb. Model 917.37758 with Honda GCV 160A GJAEA engine. Problem is that even with a sharp blade, it slides over the grass instead of cutting it especially on the left side when mulching. The engine runs fairly slow, but if I speed it up, then the self propelled drive would be too fast. I wonder if there is a blade with more lift available?