Bought an engine that has 135 hours on it. Runs great. Had Alpha I outdrive serviced by trusty mechanic including new impeller. Problem: When transitting through no-wake zone (<5 knots; <=1000 rpm) or in nuetral temp guage will read 190-210 F. Once moving 6+ knots up to 3500 rpm engine temp cools to 140-160 F. Tried playing with the outdrive tilt a bit and may change temp to 180-200 F but not much more than that. Have a closed-loop fresh water system. Am somewhat of a new-bee at this. Any help / advice is appreciated.