As recommended above, hot water and dish soap - when it starts going, don’t stop, get it on. 2x on the clamps; ABA, 316 SS. Available online in bags of 10 for very reasonable prices (1/4 West Marine’s price). Perforated clamps will eventually fail. My boat came with all perforated clamps; I replaced them as they broke until one broke on the raw water hose behind the generator. I didn’t realize it until it filled the generator pan with water. That convinced me to spend an afternoon replacing all of them.
Punta Gorda, FL