8.1 Engine Running Hot

PaulJ2 wrote:
I believe the problem here is the water pump. Wrong one is installed. There are at least two--one designed with fins designed to run clockwise the other to run counterclockwise. if the wrong one is there the water will still circulate but not efficiently. Then---if the heated water in the block can't get into radiator quickly enough,the fan clutch doesn't feel the needed heat/temperature and does not engage.
If i remember correctly this all started with a water pump replacement.
My thoughts.

This is not the first time I have heard of that "clockwise vs counter-clockwise" issue on this engine. Question is, are there 2 different part numbers? How do you tell which is which? How do you tell which you need (clockwise looking forward? or?).