A burner tube is a pipe with a row of small holes — the ports — and an open end that slides over a brass orifice. When grease drips through a rusted flavorizer and cooks in those holes, the flame goes yellow, lifts, or dies on one end. People also ruin a good tube by drilling the holes larger.
Symptoms that are ports, not the tank
- One section of the grate is cold and the matching burner section is dark.
- Flames mostly yellow and lazy after you already reset the regulator.
- Pop when you shut a knob — delayed ignition in a pocket of unburned gas.
- Flashback — flame at the air shutter or inside the tube. Shut the valve. Blockage or a tube that no longer seats on the orifice.
- Every burner weak the moment you open the tank → regulator reset first.
- One tube ugly, others fine → that tube.
Safety
- Lid open. Tank off. Disconnect the tank if the cart lets you.
- Let the box cool.
- Do not enlarge orifices. Do not poke wire into the valve.
Procedure
- Photograph the firebox: which tube is left, igniter wire, crossover clip.
- Remove grates and flavorizer bars or heat plates. A plate rusted through above the dead ports is the cause.
- Release the burner retainers (screw or pin at the back, sometimes a clip at the front). Lift the back first so the front slides off the orifice. Do not bend the orifice.
- Look into the ports with a flashlight. Shiny holes are open. Black pinholes are packed. Look into the venturi for spider webs or mud-dauber nests.
- Brush the exterior with a soft brass brush, along the tube.
- Ream each clogged port with a tool smaller than the hole (torch-tip cleaner, needle, or a bit held in your fingers — not in a drill). You are pushing carbon, not machining a bigger jet.
- Clear the venturi with a bottle brush from the inlet toward the ports. Shake debris out the inlet. A packed nest you cannot extract whole → replace the tube.
- Inspect for rust-through. Hold the tube up to the sky. Pinholes other than factory ports, or a split seam → scrap.
- Refit on the orifice. Slide the inlet fully over the brass tip until the retainer lines up. Reinstall the rear screw. Crossover tubes must clip back.
- Leak-check and test. Tank on. Soap-and-water on the tank-to-regulator joint. Lid open, light each burner. Consistent row of mostly blue flames. A dark third means missed ports or the tube is not level.
After the clean
- Even but short flames: orifices themselves may be gummed — a valve-side job.
- Even flames, still a cold line on the grate: heat plate above that tube missing or collapsed.
- Cleaned ports twice in a season: the flavorizer or heat plate above them is failed. Replace the plate.
- Tube perforated: search Amazon or BBQGuys for brand plus model plus burner. Measure length and inlet diameter. Do not buy a universal tube that is an inch short.
Related: Spirit burner replacement, Char-Broil tubes, Nexgrill tubes.