Vehicle make/model = 1998 Pontiac Grand Am Mileage = 175,000 Engine size = 6 Cylinder dash lights = no codes = none work done prior = replaced engine with another engine with 70,000 miles on it about 1 year ago. work done to repair = New Thermostat. New Water Pump tech = JK question = My Grand Am is overheating. It only begins to overheat if you drive it as long as it sits it won't overheat. The leakage is coming out of the overflow hose. The large black hose on the drivers side under the hood is hot but I can also squeeze that hose. I was told that I should not be able to squeeze that hose it should be hard. The oil and Antifreeze is not mixing. Do you think it could be my Radiator although it's not leaking, could it be clogged? What else do you suggest I try?
JK: If the car is overheating and boiling over from the overflow, then you may have a bad headgasket. Headgaskets push combustion gas into the cooling system, and cause the coolant to boil over the overflow. Sometimes the engine is not even overheating. The pressure in the system causes it to boil out. First try a new radiator cap. Then have the spark plugs inspected for signs if burning coolant. Inspect the radiator for internal restriction or have it flushed out. The upper hose being rock solid depends on the coolant temp. The higher the temp, the higher the pressure.
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