Chevrolet Repair: overheating, fan clutch, radiator cap

Question
I have just installed a new radiator, water pump and thermostat(old radiator leaked)and now I have a problem with it overheating. It's blown the top hose-replaced it-and 2 days later it over heats on a half mile trip home. No fluid in oil or vice versa. 230,000 miles. Most of the time the temp gage reads 170 and doesn't get higher until now when it overheated. Is fan clutch next?

Answer
HI Ken,

I would start with a cooling system flush.  Replace the thermostat again.  After overheating, the theromstat is shot.  

Then look for collapsing hose at the bottom.  You also have a by-pass, and heater hoses.  Your heater core could be plugged.  To tell, disconnect the two hoses from the firewall and connect them together.  If the problem goes away then that is plugged.  Try a new radiator cap, but that probably won't work.  

Fan clutch:  needs to feel free with a light drag.  If you move it back and forth, it should feel like it gets stiffer as you move it.  But no too stiff.  Could also be a dragging accessory or pulley.  Are the belts too tight?

C J S