I have a husky model C301H air compressor that I use on a frequent basis, it is a 2 stage piston compressor. While changing the oil, a piece of Aluminum foil that is used to seal the oil fell into the compressor. Is it necessary to flush the compressor and if so what do I use?

I know that I can use the recommend oil, but it is very expensive. Can you recommend a better way to flush the system out?