2009 Mercury Optimax 150 overheating issues

[7beast]

Hello everyone, we are having some overheating issue with our 150 optimax. This past weekend we took it out and it did fine for little while until we partially opened the throttle about half way and the temp alarm came on. We noticed that the "pee hole" was working fine and had plenty of water flowing thru there but the other bigger hole right under the pee hole "which i dont exaclty know what its for" had steaming hot water slightly spraying out of it. We took it home and turned it back on with the earmuffs on and we noticed it was also getting hot at idle but the water pump impeller was pumping water with no problem..According to my manual it is most likely a thermostat stuck closed. Any other opinions you guys may have?? here is some pics just for kicks. thanks to everyone in advance

 

[7beast]

Re: 2009 Mercury Optimax 150 overheating issues

Anybody??

 

[Bartine]

Re: 2009 Mercury Optimax 150 overheating issues

I believe the hole your talking about below the pee hole is an exhaust. It should be hot. What is the water pressure when idling? Mercury recommends the water pump impellers be replaced annually. I would guess impeller or stuck thermostat