I have polished aluminum teague valve covers. And am always have trouble keeping them shiny. Does anyone have any suggestions on the best way to clean/polish them?

The easiest way I have found to polish aluminum is a heavy cut automotive buffing compound and a power buffer you can use a finer grade compound after that to make them look like a chrome finish. Also go to an automotive paint supply store to get the heavy cut buffing compounds don't get it from auto parts store or the boat supply they don't have the heavy grit compounds.

They are already polished find a light grit polish with a soft wheel, then finish with a no grit polish. To help seal it in spray some water on the final polish wheel and make a few quick passes.