I hope everyone reads this. It could save yall alot of time and money.If you read my threads , 89 overheating, you will see how much trouble I had with this problem. After completely re-building my cooling system, it turned out that after the truck was wrecked, the owner installed a new radiator and since the fan blades were damaged, he also replaced the fan blade he got from another wrecked truck. Problem was, that fan was for a clockwise rotation (like the earlier models with more than one belt). 89's have a serpentine belt which means counterclockwise rotation. So, from a cold start it would overheat just sitting at idle. But if I drove it from a cold start, especially up the mountain, it would overheat and boil over in a couple of miles because the fan was trying to blow air out the front and wind was trying to come in across the radiator so it just could not cool. When I bought this truck, the owner said he replaced the radiator and that was all. In all my troubleshooting this problem, it never occurred to me to check fan rotation for proper direction until the other night when I was standing in front of the truck trying to figure out the problem and everytime I would rev the engine the air coming out across the rad was just cooking me. Finally I realized that it was not supposed to do that. So, the moral of this story boys and girls- never take the former owners word as 100%. They forget about things and make mistakes too. I hope this prevents someone from making the same mistakes I made.Popa Tim, Fords4me, and all you others who helped me on this, Muy Gracias mi Amigos.

 

Glad you figured it out!

Take care amigo!
Popa Tim