disconected raw water pump output hose to engine and had good flow, then pulled temp sensor to test. No water was present at the temp sensor port, however there was what seemed to be some black soot or carbon. My question is should water have dripped out of the port and is some soot common. My ultimit goal is to determine why and where my pump is being prevented from pumping through the engine, any ideas?..Thanks....P.S. no heat exchanger just an oberdorfer sea water pump with good output.