twin engine - both will idle around 160, go out and use the boat and the temp goes up to around 170 - 180, coming back into the marina one engine goes up to 200 - 220 before I shut it down. Why when I first start it and let it idle the temp is fine, I can leave it idle in the slip for 30 minutes and the temp never goes above 160 and when I leave the marina or use the boat the temp is fine but returning to the slip in a no wake zone the temp shoots up and I have to shut down the engine? New impeller, old one was intact (no broken pieces) Raw water cooled, my thought is the water is being restricted and cannot cool it when in the no wake zone after running the engine, but where can it be restricted at and what is the best way to troubleshoot it? Thanks Terry
