2004 90 overheating

[djstakelin]

I have a 2004 90 hsp. that's overheating. It only overheats when I run it for a while and stop the motor and let it set for about 5 to 10 mins and then start it back up. It usually takes about 1 to 2 mins to set off the soild buzzer sound. When this happens I usually rev up the motor and it goes away. I have changed the water pump,thermostat, PCV valve, cleaned water passages on both the head and exhaust side of block. I also changed the temp-sensor, but I haven't taken it out recently to check to see if the old sensor was bad. Does anybody have any more ideas about what my problem is. The Gulf temp is 93 degress

[99yam40]

Where are you located? Water temp at 93 is hard to believe.
Yamaha owners manual says to run for a few minuets at low RPM after running hard to let motor cool off some before shutting off.

Temp sensor and thermostats are easy to test on a pot of water as you heat it up and see what temp they operate at.

Sounds like you may have not replaced all of the water pump parts and it is not pushing enough water at low RPM or the PRV is sticking

[liam45]

I think 99yam40 is right.You may not have changed all the water pump parts.May be if you change them ,the problem wont occur.

[djstakelin]

I've replaced all of the water pump parts...the impeller, the gaskets, the plate, the cup, etc.. It's all brand new. I live in New Port Richey, Fl, which is near Tampa.
Also, we usually run at low RPM for 10 minutes (due to no wake zone) before coming in. The alarm goes off 30 seconds to a minute after I start it back up to drive it on the trailer.