My 1997 Camry start overheating today(180k miles, water pump has 105k miles). Massive boil over into overflow reservoir. Compression is about 150 all 4 cylinders. No water in oil. Drained radiator and refilled. Replaced fan switch, radiator cap and thermostat. No change. Engine temp guage stays in middle if cap is off but pegs if cap is on. With cap off steam comes out of radiator but lower hose is ice cold. My only remaining ideas are head gasket blown is pressurizing system, water pump is not working or radiator is clogged. Any ideas on how to diagnose would be greatly appreciated. Tomorrow I plan to pull thermostat and try running just in case new thermostat was bad or I put it in backwards. For checking the water pump I do not know which hose to pull to check for circulation. I have no clue how to check the radiator for proper flow. I would hate to replace the head gasket just on speculation. Any ideas are appreciated.

Bill

 

If bottom hose is cold check the T-stat.

Suggest you not remove any hoses to check for circulation. The pump flows a LOT of coolant and you will run out of it fast.

If you want to check pump fllow remove the T-stat out of the system. Look inside the radiator fill port, the coolant should be moving, not too fast but enough to notice.

To check the radiator flow, place a garden hose in the top with hose valve wide open. The water should come out the bottom of the radiator without backing up.