How to Troubleshoot an Overheated Radiator
- 1). Check to see there is sufficient antifreeze in the radiator. Open the radiator cap to see if the radiator is full of antifreeze. Open the overflow-reservoir to check that is full of antifreeze. If needed, use a 50/50 mix of antifreeze and distilled water. Ordinary tap water contains minerals that can build up and cause blockages in the system.
- 2). Flush the radiator with a hose if the water is rusty. If this does not fix the problem, it may be time to replace the radiator.
- 3). Treat the radiator with radiator sealant if it is leaking. Pour the sealant into the radiator and allow it to settle into the hole. Replace the radiator if this does not correct the problem.
- 4). Check that all hoses connected to the radiator are securely clamped and have no kinks of bends in them. Look for any leaks in the hoses and beneath the vehicle.
- 5). Inspect the radiator for any blown seams. Check the cooling fins that cover the heater core for any solders that might have deteriorated.
- 6). Check that the radiator cooling fan is operating correctly and all the wires to the fan are securely connected. Make sure the fan shroud is secure and free of damage.
- 7). Check to see that the fan cycles on when the car is hot and when the air conditioner is on. If it does not, it could indicate faulty wires leading to the fan motor.
- 8). Run wires from the fan directly to your car battery. If the fan works, the problem is more than likely with the wiring or sensor. If the radiator fan still does not operate, then the motor could be bad. Have the motor replaced.
- 9). Check to see if steam is escaping from the radiator cap. Replace the cap if necessary.
- 10
Scan the radiator with an infrared thermometer to check for debris or dirt that could be clogging the system. Blocked sections will read "cold" on the infrared thermometer. Flush the radiator with a hose or replace it if necessary.
