This 2.6cc engine is water-cooled and can run on gasoline, aviation kerosene, or lighter fluid. I added 2 drops of oil to the fuel for lubrication. I didn’t add oil to the crank case but I did lubricate the bearings for the test run. I fabricated the custom muffler out of stainless steel, it does quiet it down a bit but would still be loud if you wanted to run it on your desktop at work 🙂