One side steaming more than the other

[Markrhoyt]

Hello, I have a Searay 390 with twin 3208's and the port side is steaming excessively more than the starboard side. The seawater intake is clear and the impeller is new. The sea strainer is also clear. The engine is running about 10 degrees hotter than normal too. I have checked the exhaust flange on the turbo and the water holes are not plugged. If I back off the throttle to about 1800 rpms it steams normally. The amount of water coming out the exhaust is the same as the starboard side.
What am I missing here?

 

[alldodge]

It's hard to say without more testing.

Your motors are pretty solid runners. It's running hotter and your seeing signs of it, so there is a problem, finding it will be the issue. A compression test should provide most insight but it's not easy to do with a diesel

Does that motor need more or less throttle?

 

[Markrhoyt]

It's hard to say without more testing.

Your motors are pretty solid runners. It's running hotter and your seeing signs of it, so there is a problem, finding it will be the issue. A compression test should provide most insight but it's not easy to do with a diesel

Does that motor need more or less throttle?

I normally run them around 22-2300 and they both steam normally (minimal) but suddenly the port side steams excessively unless I back off to around 17-1800. They normally run around 170-180 degrees but now the port side runs 180-190. The throttle setting has not changed, meaning it does not need any more or less than before.