I will try that..... good uncontrolled test.
My engine runs cool at about 45 to 55 in 4th gear (3:31 and top loader).
Above that the temp slowly climbs to a steady 180 or 190 (puller kicks in at about, oh, 170 on the uncalibrated water temp gauge) depending on the day and circumstances. However, when my
oil temps rise up, then all bets are off. The really warm
oil adds quite a lot of thermal mass.
My puller fan and temp sending unit are originals since 1992. Amazing they are still functioning as well as they are.
I wonder what the life expectancy is on the temp sending unit and fan?