150hp Saltwater runs hot at low speeds

[Rob33]

My engine is a carburated 2001 150hp Mercury outboard saltwater edition. It runs good but heats up to about 200 degrees when running at trolling speeds between 1200 and 2000 rpms. Below 1200 rpms it runs at about 160 degrees. Above 2000 rpms it runs very good and runs at about 145.

I did change the theromstats but nothing changed.

Any help or ideas would be appreciated.

Rob

 

[achris]

Re: 150hp Saltwater runs hot at low speeds

If the overheat warning buzzer isn't sounding, ignore the temp gauge...

The engine is designed to run like that. At low speed the temp goes quite high so as to reduce plug fouling.

Chris......

 

[Bondo]

Re: 150hp Saltwater runs hot at low speeds

I did change the theromstats but nothing changed.

Ayuh,... How about the Impeller,..??

 

[Rob33]

Re: 150hp Saltwater runs hot at low speeds

Sorry, I forgot to mention that I changed out the impeller and the housing.