The grill is stainless. Soak in citric acid for vinegar for a bit and go at it with stainless scrubbies and soap. The aluminum, be careful with hard abrasives and even scotchbrite pads. They can rub off the top layer and make "black" stuff. Soap, mild vinegar and warm water. If you must, wax to shine. Get the repair kit and a MSR or Primus type needle jet cleaning tool. Oh and set it up and break it down yourself to avoid cross threading and misuse. Those knobs don't like to be overtightened. Learned this lesson on many river trips.