discovered this completely by accident after I spilled some oil while filling my oil tank. Washed it to the bilge, but didn’t really want to drain/pump the oily water to my yard, river, etc. maybe this is something everybody else already knows about or there are better ways out there, but this worked like a charm for me so thought I’d share.
Let the oil float on a little water in the bilge, and then carefully lay one of those blue paper-towel type shop towels over the oil slick so that the towel floats on top. Come back a little later, oil will all be absorbed into the towel and water underneath will be clean!
Would probably work with any other lightweight absorbent. Might need to do it a few times if it’s a lot of oil, but I was really surprised how much of a mess one towel was able to suck up!