i have a problem. i just recently had my outdrive rebuilt. sice i got it back everything is fine but when i run at wot she starts to heat up. now i can run wot with the drive pretty far down with no problem but as soon as i start trimming the drive up it starts to heay up but as soon as i back off power the temp. drops right back down. i was told that the thermistat might be hanging up. is this possible or am i dreaming.

may check oil cooler for grass.that would restrict water flow. R.B.