Soot from port exhaust..??

[ejbpesca]

Cranking the V8 GM sea water cooled engine today I noticed the water from the port side coming out of exhaust to be sooty. Starboard side clear. Once engine warmed the port side water was clear also. Can you tell me what this may indicate for the exhaust or engine?

 

[skolbe]

Is it running rich? Carb issues or wrong thermostat?

 

[ejbpesca]

Is it running rich? Carb issues or wrong thermostat?

This engine is fuel injected. Weird that only port side exhaust had the soot..not the starboard. Warmed up..soot gone...then engine ran hot.