Engine Cooling problem
1988 Chevy Blazer V8 Four Wheel Drive Automatic 70000 miles
I have an 88 K5 Blazer with a 5.7 liter. I replaced all hoses, radiater, water pump, thermostat and housing. Also replaced the heater core. The truck never overheated before but was leaking every where. After I replaced all this it began overheating. When the thermostat is in it only gets hot on the P/S of the radiator. The lower hose, heater core supply and return line, and the thermostat housing all get hot along with the P/S tank on radiator. The upper hose and D/S of tank stay cool. Some one give me some thing before set the dang truck on fire.
Almost sounds like the wrong water pump. Which belt drive system do you have? If it's a serpentine with the pump driving off the back side the pump is reverse rotation. If it has V belt drive to the pump it is standard rotation. That can be a PIA from 87-89 because they used both drives depending on the options.
The other thing could be the thermostat is in upside down. OR it is a bad one OOB. Seen that happen more than once.