So my operating temp is usually 160 and doesn't move much at all. Lately when surfing as soon as I come off the throttle to idle, operating temp spikes about 15 degrees and I smell the engine running hot. After a little temperature returns to normal. All throughout surfing engine temp is stable. Week long vacation to lake Norman next week and I don't want this to be a precursor to something more serious. Any help is greatly appreciated. Surfing with 750 in locker, 400 up front, 3 people in boat with driver, stock prop.