I don't think my 1999 F150 is reaching normal operating Temp. Radiator hose doesn't feel hot enough, plus heater blows only warm air. Blend door is working.

My question is: does the temp gauge show an actual reading or only some type average? My gauge always reads mid scale after warm up. I'm thinking about replacing the thermostat

Any suggestions? JIM

 

I would agree.

 

I too agree. Have had this same issue with more than one vehicle. Should be a couple different temps of thermostats available. Higher temp thermostat won't give you hot air as fast but it will be hotter when it does.

 

The normal operating temperature is 195+/-.
Do not use any other temp level cooler.
Be sure the air is purged out and best it can.
Operating temperature can be seen using a Scanner viewing live data.
Be sure there are no leaks and the system has vacuum when cooled over night if the fill jug cap is slowly released to hear it.
Good luck.

 

When I replaced my radiator & thermostat several years ago, I put a lower temp thermo in. The temp never goes above 176. What damage might this be causing?

 

In a computer controlled system it causes higher fuel consumption due to the temperature sensor's signal to the computer that causes fuel injection added richness. Why? The Mass Air meter, the cooler water jacket all affect the amount of fuel injected such that the intended air to fuel ratio is shifted. The OX sensors cannot correct a forced change like the thermostat, even though they try.


This can generate more carbon in the cylinders, coat the Ox Sensors and lengthen their response sensitivity, coating the cat somewhat with the richer by products, making fuel injection 'control' ever more degraded over time.
It all becomes a degradation away from the original design.
As for damage, not much as you see so far.
Damage is more a fault from excess wear or outright failure.
You did not gain anything with a cooler thermostat for normal use.
Piston expansion and cylinder diameter changes are not as designed for at that temperature.
On the street as they say, it's hard to show some of the effects in anyway but referring to the science and engineering the change could likely cause.


If you were to look at the long term fuel tables, then change the thermostat to the specified temperature then look at the tables again after giving sufficient time for system readjust, you could see the effects of just your change as proof you forced the system to run at a different point from the design temperature intended.
.
Some other forced changes is the spark plug heat range is not what was intended at those cooler temps, the Ox Sensors are not working in their intended heat range and the list goes on.
Another difference you likely see in winter temps is longer system heating time and engine stays at high idle longer upon a cold start. These effects cause more fuel consumption.
.
Will codes be set, no because the system has a performance range built into the program to allow the motor to run with degradation or parts tolerance off normal so the driver is not hassled by every little change or minor wear.
The system actually accounts for wear over the life of the hardware until a limit is reached then you get a code.
.
Can you get away with it, sure.
There is an old saying that goes like this; Often what you don't know don't hurt you. It does, but you don't realize it until something happens, then you may still not know the cause.


Good luck.

 

Thanks Bluegrass. I appreciate all that info.

Is it true that the oil wouldn't be getting hot enough to burn off any moisture & contaminates & be creating sludge?

Since I still have the original heater hoses, I'm concerned about them failing. Would that be more likely at higher temps?

 

Cooler temperatures does affect the cleanliness of the engine overall.
Cool surfaces offer a place to condense combustion byproducts.
One place is the fill cap that gets a milky accumulation under high humidity conditions and cold temperatures.
Heater hoses are more subject to heat and Ozone breakdown plus the chemicals in the coolant. They are replaceable as an expendable item and under normal maintenance.
The thermostat you have in place is almost at the point a code will set.
When the engine is started from cold, a software timer begins.
If the temperature does not rise above about 173 +\- a few degrees in a set amount of time when the engine is expected to be at normal operating temperature, a code is set to tell you there is a cooling system issue.
Put the correct thermostat in place.
Good luck.

 

I foresee myself doing that in the very near future.

Thanks again!

 

I replaced the thermo with a new Motorcraft one. Now temp stays around 200.

How high can the temp go but still be ok?

And should the coolant level change when at operating temp?

 

if you replaced with a 195 degree thermostat , your right on good at , 200, I would start to worry if ya start getting or , staying in the 250 degree range, over flow tank should be at max level mark when engine is up too temp, sounds like your good to go,, a new radiator cap never hurts either

 

Thanks Todd.

 

I'm finding it rather interesting that the level in the bottle doesn't seem to change at all between cold & the 200 degrees I'm seeing now.

 

how old is your radiator cap,, that would be the first thing I would look at,,