My motor runs at 180 degrees. Is this to hot for this motor? It has been this way since day one.

After a hard run mine will run up to about 180, but then it cools down to about 170..

My port runs about 180 and the starboard about 175

As long as your oil temps are staying below 250F after WOT runs, 180F coolant temp is fine.

BT

At 250F most conventional oils are cooking.

Bikinilover
The Merc. 496's come with a closed cooling system and a 160 degree thermostat. Most engines will run about 10 degrees warmer than the stat under light load conditions and may go to 20 degrees after a hard run. The temp of the water you are running in will also raise your operating temp depending on where you are boating.You might want to check your temp guage for calibration, 5 to 10 degrees off on some is common. Also make sure your coolant cap is holding pressure as a pressure leak here will raise the cooling system temperature some also. Doesn't sound like you have any serious problem as the Merc computer would go into the guardian mode if you were to hot.
Raylar

Thanks for the input! Sounds like I am OK. I will change the impeller at the end of the season for piece of mind.