I have a Worldcat catamaran with twin 2019 Yamaha 115hp 4 stroke engines. Accessing the flush fittings is very difficult while the boat is in the water. I am hoping to setup a system where I can attach the hose inside the back of the boat to flush the engines. I have seen this done on other boats, and even seen kits to allow this to be done. My biggest problem is that, even with the cowling removed, I can not find where the existing flush hose goes into the engine. The hose disappears under the engine.