Steam is more prevelant on starboard motor. Recently replaced or serviced turbos, heat exchangers, gear cooler, after cooler. I am wondering if the exhaust system on this model normally produces steam when cruising.
are you certain it is steam and not white smoke? Steam will dissipate relatively quickly whereas smoke will linger and trail behind boat.
Steam can be more noticeable in cold water but if conditions are normal and one side is noticeably putting out more steam then usually the first check is on your raw water side. A bad impeller or a restriction in one of the coolers or HEX can limit the amount of water getting through and allow exhaust to heat up. If you have an IR thermometer get someone to run the boat and check temperature at exhaust riser where water is injected. Both sides should be close to the same temp.
Another symptom can be coolant temperature rising as you increase engine load. Poor raw water flow will not allow the heat exchanger to reject enough heat.