Ive got heater hose from the water pump to the heater core thats fine I have a hose from the heater core to a T fitting one goes to the raditor thats fine but one goes over to the passenger side head, they seem to be return lines, I dont see this as a must the new heads I put on dont have that. 1991 F250 7.3 navistar non-turbo IDI looking for anyone who might have a reason that it needs to go to the head.?????

 

for the heater the lines go from waterpump to heatercore, then back to right side head.

never seen one that went to the rad.