Burner Inspection, what to look for .... The burner is the heart of your grill and should be inspected and cleaned on a regular basis (several times a season depending on usage) to keep your grill effective, efficient and in safe operating condition.    Proper operation is indicated when the burner flame burns evenly around the perimeter of the burner at all control settings. How to clean.   Remove the burner and using a wire brush clean the exterior of the burner to remove loose corrosion and excessive residue. Clean clogged gas holes with an opened paper clip. Use a venturi brush, (you can also use a coat hanger with the tip bent in a small hook-shape),  to clean possible blockages by insects in the venturi tubes What to check.  Check the burner assembly for corrosion damage paying particular attention to the seams along the edges near the burner ports.  The seams, or those areas where the metal is folded over in manufacturing, often trap grease and this is where corrosion generally begins.   Apply pressure with your thumbs to the solid metal areas of the burner to check for weakness.  Check cast iron burners for clogged holes and/or flaked away openings which cause the burner ports to increase in size and create uneven burning. When to replace. Rusting and discoloration is common for all types and materials including aluminized steel, stainless steel and cast iron.  Excessive rusting where the burner is splitting at the seams or has holes rusted through need to be replaced as do cast iron burners which have "swollen shut" or "opened up". How long they last. Depending on climate (lookout Seattle rain makes rust!), location (salt water is corrosive!), usage (yikes even the food acid is detrimental!), your burner will last 2 to 5 years depending on quality and materials.  Yes this includes cast iron!