Ford: 2000 ford ranger, upper radiator hose, circulation problem

Question
my heater is blowing cold air  i changed my thermastat and still blowing cold air my radiator cap is cold my hoses is not real hot know it is making a sqelling noise sounds like the belt creaming dont knowwhat it is

Answer
Hi.


When your engine is warm (after about 5 minutes of driving) you should feel warm to hot water at your upper radiator hose and at at least 1 of the heater hoses.

If you have heat at both heater hoses, i would suspect a heater blend door,

if only 1 hose is hot, you may have a circulation problem or air lock or plugged heater core.

Let's start with circulation:  you have a squeeling.  Are the belts tight?  You do not state which motor you have, but remove  the belt and see if you can spin the water pump. if not= the pump is seized or stuck. If yes= replace and adjust the belts. squeeling should stop.  Squeeling can also come from a leaking water pump, leaking onto the belt. Inspect the pee hole under the water pump for signs of coolant. Coolant= replace water pump.
Start the truck and carefully remove the rad cap.  You should see water moving.  A stuck thermostat will still allow water to the heater , but restrict it from the rad.  A proper flowing and cooling rad should have hot water going in and cooler water coming out of the rad.

As for an air lock, I choose to pinch off one rad hose until the heater has hot water in and out, then remove the pinch off.

When you replace a thermostat, be sure that you have bled the air from the sytstem as air does not gat hot enough to open the thermostat in enough time.