I believe this is the knock sensor. I was able to disconnect the wires/connector that go to it. Is there anything special about removing it? It looks like its just a simple deep well socket or box wrench. It's the 1st time to winterize an inboard so thought I'd check before I start.
My plan is to warm the engine, drain the block, blow out the heater, unhook the water intake hose from the block, replace with a shorter piece of hose which will run to a large bucket of antifreeze, start the motor and let antifreeze run into the system. Similar to what I did for my I/O but insteah of using muffs I'll use the bucket/antifreeze. Will be fogging the motor, changing oil and transmission fluid during the process. Thanks folks