21. 281658S Briggs Flat Head Oil Fill Plug

This flat - head engine oil fill plug, formerly numbered 555037, is a reliable choice for your engine.

To use this oil fill plug, first make sure your engine is cool. Then simply screw the plug into the designated oil fill hole until it's snug. Don't over - tighten as it may damage the threads. For maintenance, check the plug regularly for any signs of wear or damage. If you notice any cracks or if it doesn't fit tightly anymore, it's time to replace it. Keep it clean to ensure a good seal and proper engine performance.