Running hot!

[jpd]

For the past few days my 2002 LS has been running hot. The fan seems to run continually and if I'm not moving the temp gauge goes up. All the fluids are topped off and I cleaned the outside of the radiator. I'm wondering if it the thermostat is sticking closed. And thought's?

Thanks
John

 

[Jim Henderson]

Could be several things.

Staying cool only while moving hints at possibly bad fans or controller, or poor water pump circulation which could be the pump, thermostat or even clogged passages inside the radiator and engine.

I am not sure if you have those weird hydraulic fans or electric ones. I think either type is computer controlled. Usually when you turn on the AC to max with recirculate, the fans will come on while at idle. Not sure on the LS since I haven't had this problem. If there are two fans, this will usually force both to come on.

So try turning AC max, recirculate and watch the fans before and after turning the AC on.

You could also remove the t'stat and inspect it. Sometimes it will be obvious that it is broken. Othertimes you could put it in a pot of water and heat it til it boils. The T'stat should open up as it gets to boiling.

YOu could also squeeze the hoses while the engine is hot and running with you or someone playing with the throttle. You should feel the water surging thru the hoses and the hoses should not collapse.

Good Luck,

Jim Henderson

 

[jpd]

Now it's no longer staying cool while moving. Today it got hot to the point where the engine went to reduced power mode and the check engine light came on. I'm thinking the fan and controller are ok because the fan runs continuesly after a sort time. Trying to keep the engine cool.

 

[jontz]

I would change the thermostat first, since it is the cheapest. Next, check the water pump. Last step would be the radiator itself. If there is a flow problem through the radiator, a good service shop should be able to spot that.

 

[jpd]

I tested the thermostat and it's junk. I'll get a new one tomorrow.

 

[girty]

BLEED the system

make SURE you bleed the system !! I made the mistake of not doing that.I have a V6 and the plug is on the long pipe from the T-stat it has a hose coming out of it. becareful because you can break it.

 

[girty]

heres a link!!

http://www.lincolnvscadillac.com/tech/Lincoln-LS/CoolingSystemDraining/

 

[jpd]

make SURE you bleed the system !! I made the mistake of not doing that.I have a V6 and the plug is on the long pipe from the T-stat it has a hose coming out of it. becareful because you can break it.

Thanks for the tip. I did fill under the engine fill cap but I didn't bleed the heater.

John