Overheating update...more help please :(

[Richard Lange 2]

This is a follow up to an earlier post about my truck sending boiling liquid in to the resevoir after I turn it off.



I have now flushed the system, changed the radiator cap, checked the hoses, and replaced the sensor behind the thermostat. The water pump and thermostat were changed more than a year, but less than 2 years ago.



As before the truck runs fine in the morning and at lunch time with the AC on. But on my 45 minute drive home with the AC on it started "acting" like it was overheating (truck will run fine without AC on). I say "acting" becuase it felt like it was not shifting right, but the gauge on the dashboard was between half and 3/4s of the way to overheating.



I turned off the AC. The resevoir DID NOT have boiling fluid (yeah ... a small victory), but this is the 1st time the truck has felt like it was overheating. Grant it the ration is off a little bit becuase I have been adding water and radiotor fluid at each of the interludes, but I doubt it is anymore than 66% water 34% anti-freeze. Could that be why I got a whole new issue today? No boiling but over-heating like conditions? Although why would the truck drive like its overheating, but not show over-heating on the dash board?



Does anyone think this sounds like a thermostat problem? I asked before, but did not get a very good answer ... why does Ford make a 180 degree thermostat if you are supposed to use the 192? It seems like the 180 could solve my problem of the truck getting too hot.



I have a brand new 192 degree thrmostat in my hand. I am at a loss on whether or not to put it on.



HELP!

 

[Tom Schindler]

With a computer controlled car, running a cooler thermostat is not something to do. A cooler thermostat can cause your engine to run in a warm-up mode causing your fuel mileage to suffer.



Replace the thermostat with a new one.





Tom

 

[Ron N]

well in my experience if you even think it is a t stat problem Pull it out and leave it out for a day or two.That will tell you if it the thermostat.If it still over heats, then it might be the fan clutch is going out. Ron

 

[Chuck Birnie]

Change the thermostat. Also check to make sure that the gasket behind the water pump isn't leaking or sucking air. other than that I'm at a loss. Good luck!

 

[Ron N]

Start the engine and allow the engine to run for 10 minutes.

Feel the inlet and outlet heater water hoses and the underside of the upper radiator hose.





Are the upper radiator hose and the heater water hoses cold?

Yes

INSTALL a new water thermostat. TEST the system for normal operation.

this is also a sight for information on the subject. Ron

 

[Richard Lange 2]

none are cold. all are very hot

 

[shawn stonbraker 2]

I would change the thermostat still. I would also check your radiator for any fins being blocked/damaged. The thermostat may not be opening all the way causing it to not completely overheat, but not enough to keep it cool. Just a thought.

 

[EddieS'04]

I wonder if, when the AC is on that the fan clutch is not turning fast enough, to draw in enough cool air...The AC condensor is in front of the radiator, it runs fairly hot,air passes across it before the radiator...the fan has to draw enough air to cool the condensor and radiator with the AC on....



Go ahead and change the t-stat first...I have had new ones fail to open properly...

 

[Richard Lange 2]

ran out of time tonight ... will change tommorrow after work. I will post the results. Thanks for all your help!