Boat is running hot with very little water coming out the pee hole at idle.  I back flushed the engine and got out a lot of sand but still running hot (190 or higher at idle).  Engine is not running lean and must have blockage.  Before i pull everything apart are there any "usual culprits" that cause blockage?  I'm assuming that the water line to the jet is just an opening in the bowl (i blew into the line and it is clear).  Any suggestions?