Cat 3116 steam in exhaust

I just got home from a 600 mile round trip to the Fla. Keys and I am seeing steam in the exhaust from the port engine. It dissipates within 20 ft. When cruising at 7 knots I do not see any steam, but at 2400 rpm cruise it is there. The port engine runs 10 degrees warmer than the starboard engine so I am hoping that the warmer exhaust water hitting the cooler seawater is what is causing it. Not holding my breath though, just keeping fingers crossed. I have put about 800 hours on the engines since pulling, cleaning and pressure testing h/e, aftercooler, and trans cooler so I am going to do that next time at the boat, also will check raw water impeller. The antifreeze is about 1 pint lower than it was and if it makes a difference, I only use Cat products on my engines. Does anybody have any ideas for things I should check? Unfortunately, I am out of state on business and will not be home for about 2 months, so I have lots of time to drive myself crazy with worry while imagining all the terrible things this could be. Any and all ideas would be appreciated. Thanks

I;m not sure why you would be getting steam on a 3116 and not having coolant problems.

Get with Justin at DNA marine in Tarpon Springs. he's mobile and knows his stuff.

I can see steam from my exhaust also. Sometimes port side sometimes starboard side sometimes I don’t see any. Seems to depend on air temperatures and the sun shining the right direction. Only happens on plane. Engine temp is also higher on port side on dash gauges but exactly the same (185) on master gauges on engines

If you have the heating coil in your water heater connected, then the stud engine will operate a bit cooler than the port engine. This is because the cooling system holds more coolant because of the heating coil. With a larger volume there is more coolant to dissipate the heat.

Hopefully not 800 hours on the raw water pump impellers..... For some reason the 3116 engines eat impellers; I had to change every 200 hours and, typically, they were pretty chewed up with missing pieces. You should see no steam and the engines should operate the same temperature.

One thing I noticed in the Op was that he did lose some antifreeze. I would get someone in there. I would also keep an eye on that antifreeze. My buddy just had same problem with a detroit and it was a cracked manifold. Not typical, but does happen.