ran boat empty this weekend thanks to a bad fuel sender and a teenage boy who just keeps wrecking my stuff. filled up with gas to get home and temp alarm went off. Idled fine seemed just a high rpms is when the alarm occurred. Iwent through everything and beleive the pressure relief valve was stuck because when I took it out it was **** eyed in the spring when i pulled it out. Ran it and checked engine block after running at 4700 for 10 minutes or so and the engine block and thermistor read about 120ish. Checked it against the other engine and seems to be simmilar (so I think I got that one licked) however the larger problem is that when I had the cowlins off I notice the same engine had a knock to it. Now I just changed the water pumps in september and everything seems to be flowing properly out the tell tale. This engine maintained with LOVE since I owned it but this is the first time I did the pumps (so I'm nervous). It sounds like the sound is coming from the rear of the motor all the way down to where the lower unit shaft connects to the power head. Check compression and all read between 110-115 and have spark on all plugs. It also is knocking when I through it in gear at the dock at about 1200rpm can't here at WOT. Please Help! Rodbolt or any yamaha guys Ray, Etc