I have an older boat, it has a 1992 502 carbed with Corsa Quick and Quiet, the boat has been running warm lately when I switch to quiet mode, the boat runs 150 with the thru hull open climbs to 170-180 thru the drive. Is there anything in particular I should look at? The engine has under 500 hours and runs great...

I should mention the lake I run in is over 80 degrees currently

What RPMs do you run at with the exhaust switched to quiet? You are not supposed to run over 3000RPM with any of those systems in closed/quiet mode.

probably slightly over, 3200-3400 easy cruise speed. Anytime I run hard I open up,