I replaced my radiator because my engine was getting hot and the check radiator and temperature light were flashing very often. After I changed this they both stopped coming on. Now I started realizing when my fan was going to come on to cool the engine. I haven't heard it come on yet but my temperature gauge hasn't shown hot and the light hasn't come on either. Should I drive it or what?
A cooling system has many components that can fail and cause a hot engine. The radiator could be clogged or have a leak. However, you could also have a bad thermostat, water pump, a fan that is not working or a leak anywhere in the system. There are component tests and leak tests that can be performed to find out exactly where the system is failing. For your fan to turn on, the engine must meet its maximum operating temperature. If you're not sure that this is working properly, it might be a good idea to have it looked at by a qualified technician. Without a completely properly functioning cooling system, your vehicle could over heat, which sometimes happens suddenly and could cause damage to the engine.
〉 Answered on Jun 16th, 2008 by Suzanne Grego, Technician at City of Philadelphia Fleet Management