My coolant fan is not working what should I look for

[tpfeifer]

Hello,
I have a 1999 Mercury villager> I just recently replaced a coolant hose on the back of the motor.
The coolant fan was working before I replaced the hose. Now the fan is not working. Any ideas what to look for to get this fan working?
Thanks, Todd

 

[wip99gt]

The first thing I'd check is the fuse, if thats good then it is most likely an airlock in the coolant system. The rad fan is thermostatically controlled. Temperature senders need to be in coolant for them to work and they're usually located along the top of the engine where the airlock could be. Some vehicles need an air evac coolant job so you might need to take it to a shop to get it done. One thing you can try is to park on an incline and with the radiator sitting highest the air might work it's way up. There's also a strong possibility there's a sensor or plug at the top of the engine you could pull to get the air out but as I've never worked on one of those I don't know where it'd be.

 

[PhilFrisbie]

I would also suspect an air bubble. My Aerostar was a pain to 'burp' whenever I worked on the cooling system.

 

[bryanl]

The fan should always run when the AC is running. If it does, then the fan and its relay are OK, but the water temperature sensor (or thermostatic switch) could be bad or have a loose cable. There may also be a water hose containing 1-3 temperature sensors/thermostatic switches.