Engine is running hot

ANONYMOUS

MEMBER
2002 CHEVROLET IMPALA
187,000 MILES

My Impala, is running hot. Changed the thermostat, water pump, radiator and cap, head gasket. The car starts out running fine and I have heat. Car starts over heating, heat quits and electric fans come on and starts blowing coolant out. Do you have any ideas on what I need to do now. I am really stumped. I feel the fans wait to long to come on. Was told my new thermostat is set for 195, and that was the coolest they could put in it.

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

Just to clarify, you have coolant comes out of the radiator before the fan kicks in?
First you need to test the radiator cap.
As since the engine is operating at the correct temperature, the radiator cap should not burst open or leak out.
Every radiator cap has certain pressure rating depending on the operating temperature of the engine.
Over time the springs inside the cap that reacts to pressure goes bad and becomes weaker. When that happens the cap releases coolant at a lower pressure and temperature than it is designed to.

The radiator cap can be pressure tested to verify its working condition.
Just about any parts store will have a radiator cap tester that you can use.

https://www.2carpros.com/articles/how-a-radiator-works

https://youtu.be/W8kra65m15c

Please let me know of any questions.

Thank you.