I just installed new water pump on my 40 HP Mercury. Has been working fine. Got stuck in marsh mud Saturday. Nothing out of pee hole. I backed out bolt between plugs, water pumping fine. Motored about 30 minutes back to landing, no problems, motor cool to touch. Rubber pee hose not clogged. Question? Can I take off pee hose and blow out where hose attaches with air. I have air compressor or will I damage something in fuel or other system? If I install a water pressure gauge is the weep hose necessary?