I have a 2011 F150, 5.0 and was wondering what normal coolant temperature should be. The OEM themostat is 195F but using a scan tool the temperature is running 211-228F at 75-80 ambient temperature. The temp gauge never indicates a temp change from normal hot operation.With that said water boils at 212 degrees and for each pound of pressure, (radiator cap is a 16 pound) you increase boiling point by 4 degrees. So this would set a running hot, boiling point at 278F. The high speed cooling fan is coming on more than it used to is the reason I ask others if they may have the technically specific information on their 2011 5.0's. This all started after having an oil cooler leak contaminating the cooling system. I have flushed and cleaned the cooling system and there is no sign of contamination left. Through the flushing process I encountered issues removing entrapped air but it is operating fine now it appears, ( no coolant level drops, no visual or audible signs of overheating, etc., but the high speed fan comes on more than it used to.

 

Your math is off - it's closer to 3 degrees per PSI. Also, ethylene glycol coolant boils at a higher temperature than water. With 50/50 coolant under 15 PSI, it boils at 265.

I wouldn't worry about 228, but you may want to replace the thermostat on general principle. Get a Motorcraft thermostat, not aftermarket. Stock is 190, not 195.

https://www.rockauto.com/en/moreinfo...015590&jsn=449

 

Thanks for the feed back! My 4 degrees was from years ago reference. The original thermostat from Ford was marked 195 degrees, it has never been changed until I did. Maybe they since have changed specification?. Anyway I did change it to a like degree rating, not Ford. Even at 3 degrees not allowing for the coolant with a 16 lb cap is 260 degrees. I would like to know if anyone has real time temperature data on their 2011 5.0's. I know scientifically, (math above) I am not approaching overheating but would like to know if it is still higher than it was previously. As you mentioned I have suspected my replacement thermostat but also suspect CHT, (coolant head thermistor) calibrations may have been altered during the flushing/purging process. Have disconnected A/C high pressure switch to no effect so that is not causing the fan issue. My understanding is the high speed fan controls are engine temp, A/C pressure high, A/C on. Does anyone know of more controlling input factors?

 

Marty, I moved your thread out of the "Forum Suggestions" to a section that is more appropriate.

As glc said, I would not worry about the temperature you are seeing. And, the dashboard gauge is little more than an idiot light. It will show mid-range as long as the temperature is warmed up and will only go to hot if there is a severe overheat. Also, as I think you may know from your last post, the coolant temperature is not actually monitored, but is inferred from the Cylinder Head Temperature (CHT). Engine Coolant Temperature (ECT) is not monitored because if it boils, and turns to gas, the sensor can't read it properly.

I used to see 225-230 CHT on my old 2005 5.4L King Ranch when it was under a heavy load in the summer. Otherwise, it ran somewhere in the 215 range.

Here's another point. Once the thermostat opens fully, the temperature is controlled by the radiator efficiency, the fans, the outside air temperature, and your engine load. The thermostat is simply there to get the engine warmed up quickly (good). If you switched to a lower temperature thermostat, it would just slow the warm up time of the engine a bit (bad), but the final operating temperature would still be what you are seeing now.

Hope this helps.

- Jack

 

FWIW ...
.

 

Thanks Jack, sorry about post location. I am new to forums and have much to learn. I agree with most you said other than the CHT function. It is a more precisely calibrated temperature monitoring device, thermistor, than the old units which were bimetallic thermal and just increased ground to produce gauge reading. The thermistor type, (which I use at work as an industrial maintenance technician) is more real time and accurate than the sender of old times. With that said, if overheating becomes so turbulent that steam, air pockets develop it can alter the accuracy. After research I have learned that due to the use of resistors in thermal circuit capability the calibration is set,unchanging and a unit of this type most times is good, continuity or bad, no continuity.
Your temp ranges also answer my question. Under our ambient temperatures here, 75-80F the truck is running 228F down the road no load. I have noticed a slight and I mean slight, 1/8" gauge movement which I think may be indicating the thermostat which should be fully open is throttling. Will change it and see what happens.
Again thanks for your time and input.

 

Thanks!! Exactly what I was looking for. Have searched and searched for that number, 215F.

 

That's too HIGH. Personal experience (under same conditions - ambient temp', no load, etc.) is 195-199°F with an occasional, albeit brief, spike to 201°F.

+1.
.

 

[QUOTE=gDMJoe;5248940]That's too HIGH. Personal experience (under same conditions - ambient temp', no load, etc.) is 195-199°F with an occasional, albeit brief, spike to 201°F.


Thanks, already have new one.

 

Just thought I'd respond about my '11 with a 6.2. A few pics from my SCT Livewire. Assume the Livewire is fairly accurate? It shows outside ambient and engine temp. and high/low. Last two pics. are while towing a 7x14 V-nose enclosed trailer with my Polaris Ranger out to my place in West Virginia.

 

Looks good to me.

 

it happened to me, high speed fan kicking on at random and dang its loud, chased that ghost for a while and it eneded up being an aftermarket thermostat that failed to open, put a ford branded back in and fixed, such a simple part can cause such grief