1994 Yamaha 85hp overheating alarm issue

I have a 1994 C85T that is giving me the overheating alarm. The alarm comes in after a few minutes of running at higher rpm - when I stop and turn off the engine, it clears and I can go again for a short time. Seems to be speed dependent. Takes longer for the alarm to come in at half throttle than if I run it wide open. Anyway, I've replaced the impeller and the thermostat. The engine is pumping water and doesn't feel like it is actually overheating. I've pulled out the temperature sensor and tested it by putting in hot water and it appears to be working correctly, although I'm not sure what temperature it is supposed to trip. Any ideas? I'm going to try pulling out the thermostat - maybe a flow restriction issue? Then I'll try a new sensor.

Thanks!

Randy

Pressure Control Valve

I'm looking at a couple of the other posts. Could the pressure control valve be an issue? There is no hose on my motor (like on the 115hp), so I don't know where the water goes if the valve is stuck open? I had the motor in the shop a week ago trying to figure this issue out and they saw water leaking out at the bottom of the power head - under the cylinders. The repair shop thought it was a bad gasket - that was allowing water to leak out of the water jacket. We pulled the power head and replaced the gasket - but still have the temperature alarm.

[boats.net]

The pressure control valve is under thermostat, number 40 Yamaha Outboard Parts 1994 C85TLRS CYLINDER CRANKCASE Diagram
May need to replace water pump using a water pump repair kit 692-W0078-01-00 and new housing 688-44311-01-00.

How can I tell if the PRV is leaking?

Thanks - I already replaced the water pump, impeller and the thermostat. I'll try the pressure control valve since I think the temperature sender is working. Is there any easy way to tell is the pressure control valve is leaking?

[boats.net]

It will have something between valve and seat preventing it from closing.

Prv

I'm trying to understand where the water goes if the PRV is stuck open? Where will i see the water coming out?

[jb123]

upper exhaust

[renagade4x4]

i also have a 1990 85 hp cv85etld and the alarm keeps goin off and wont throtle up when it goes off it also at full throtle will bogg down and want to die i am goin to replace the water pump but what else could be my problem please help im at my wits end