5. Reinstall the spark arrestor screen, clip, muffler cover and screws. 17 MAINTENANCE & REPAIR INSTRUCTIONS CHECKING THE OIL LEVEL CAUTION: To prevent extensive engine wear and damage to the unit, always maintain the proper oil level in the crankcase. Never operate the unit with the oil level below the bottom of the dipstick. The importance of checking and maintaining the proper oil level in the crankcase cannot be overemphasized. Check oil before each use: 1. Stop engine and allow oil to drain