7.3 High Engine Coolant Temps on Dashcommand App
#1
04-28-2017, 07:49 PM
7.3 High Engine Coolant Temps on Dashcommand App
Question. I've been using the Dashcommand iOS app to monitor vehicle specs on my 2002 F250 with a 7.3. I like the app, but recently started looking at (ECT) engine coolant temperature. The readings look a bit hot to me at 225-235 at 70 mph, fluctuating a great deal. From what I understand, the ECU cannot actually report the ECT, and actually uses other readings to estimate the ECT. The dummy gauge on the dash, never moves past normal after reaching operating temp. Do you guys think the high ECT readings on the Dashcommand app are something to worry about? I'm thinking it may be bad data. Thanks.
#2
05-19-2018, 10:09 PM
Well, after a year, I guess I'll reply to the GA Nut...
I doubt he'll read it, but maybe this information will help someone new to the problem.
I would be interested in what range a "great deal" falls into. The temps will fluctuate a bit, but not much if speed and load (hills, etc) remain fairly constant.
If you are having rapid swings of 5°, or more (happening in seconds, not minutes), I would suspect you are boiling off in the heads.
That would indicate a faulty pressure cap, or improperly mixed coolant.
For a stock truck (192° Thermostat), 225° Coolant Temp is a bit high.
I would expect Oil Temp to be about 225° (after driving the truck at 70MPH for 30 minutes or more), and Coolant to be 210-215°.
That kind of Coolant temp at 70MPH (unloaded) could indicate your radiator is full of dirt.
They do that. A LOT.
No. That is false information.
The Engine Coolant Temperature (ECT) Sensor is on top of the Water Pump, beside the Thermostat Housing.
Unplug it, and you immediately lose your ECT reading.
It's about as direct as you can get.
"Dummy Gauge" is an accurate term. The gauge effectively has 4 "ranges".
COLD - It's stuck on the pin
WARMING - The gauge moves... at about the speed of smell. It's position means nothing relative to the actual temp of the coolant.
OPERATING TEMP - Usually somewhere just under the 1/2 mark. Again, it's position means NOTHING relative to actual engine temp.
Once it reaches that spot, it won't move again, unless the ECU says "Too Hot".
180°, or 225° = the same spot.
HOT - I don't know the exact number, but probably about 250°. Way hotter than I would ever want my engine to get.
Also accompanied by excruciatingly SLOW needle movement. By the time it actually hits the red, you are WAYYY past "overheated".
And, if I need to say it again: The needle's position has NOTHING to do with actual coolant temperature.
For instance: If you have a catastrophic coolant blowout (say the lower radiator hose gives up), you can be out of coolant in seconds. Pulling a load, that translates to immediate overheating.
The needle may take minutes to register the change. Often, in such a scenario, the OIL/COOLANT indicator light will turn on while the needle is still in the "Normal" range.
"High" is relative, but yes - I'd be looking at those numbers. I'd want to know what EOT was when ECT was 225°.
Further, Dashcommand's data is likely to be far more accurate than anything else you would be seeing.
225° EOT @ 70MPH would be about average with a stock radiator.
225° Coolant is pretty hot. If your Oil Cooler is in good shape, that's still 235+° EOT.
235° Coolant (245+° EOT) is probably an accident waiting to happen.
The radiators are a little thin. Even the 8500GVW radiator only had a 1-7/16" thick core from the factory.
Many cores were only 1".
And, as I stated above, over time they fill up with dirt.
At 10 years, I removed my 1-7/16" core radiator, pressure washed it, and painted it.
It helped a lot. The area directly behind the fan was absolutely full of dirt.
Before I pressure washed it, you couldn't get light through that area. After I pressure washed it, you could read through it.
I'm not kidding when I tell you those radiators fill up with crud.
At 15 years, I replaced my radiator with a 2-1/4" core. It helped tremendously with interstate speeds and big, wind-catching loads.
Here's a tip for anyone with Dashcommand or Torque:
Check your Oil Temp (EOT). It's more important than the Coolant Temp (ECT).
If the Engine Oil Temp is up around 225*, the coolant temp should be between 210 and 215 degrees.
If it's more than 15 degrees different (at 225* EOT), you have problems in your Oil Cooler.
But, that number is relative. If your Oil Temp is only 195*, EXPECT the Coolant to at least 25* lower than EOT...
If your EOT is routinely going over 230°, you have a problem.
I doubt he'll read it, but maybe this information will help someone new to the problem.
If you are having rapid swings of 5°, or more (happening in seconds, not minutes), I would suspect you are boiling off in the heads.
That would indicate a faulty pressure cap, or improperly mixed coolant.
For a stock truck (192° Thermostat), 225° Coolant Temp is a bit high.
I would expect Oil Temp to be about 225° (after driving the truck at 70MPH for 30 minutes or more), and Coolant to be 210-215°.
That kind of Coolant temp at 70MPH (unloaded) could indicate your radiator is full of dirt.
They do that. A LOT.
The Engine Coolant Temperature (ECT) Sensor is on top of the Water Pump, beside the Thermostat Housing.
Unplug it, and you immediately lose your ECT reading.
It's about as direct as you can get.
COLD - It's stuck on the pin
WARMING - The gauge moves... at about the speed of smell. It's position means nothing relative to the actual temp of the coolant.
OPERATING TEMP - Usually somewhere just under the 1/2 mark. Again, it's position means NOTHING relative to actual engine temp.
Once it reaches that spot, it won't move again, unless the ECU says "Too Hot".
180°, or 225° = the same spot.
HOT - I don't know the exact number, but probably about 250°. Way hotter than I would ever want my engine to get.
Also accompanied by excruciatingly SLOW needle movement. By the time it actually hits the red, you are WAYYY past "overheated".
And, if I need to say it again: The needle's position has NOTHING to do with actual coolant temperature.
For instance: If you have a catastrophic coolant blowout (say the lower radiator hose gives up), you can be out of coolant in seconds. Pulling a load, that translates to immediate overheating.
The needle may take minutes to register the change. Often, in such a scenario, the OIL/COOLANT indicator light will turn on while the needle is still in the "Normal" range.
Further, Dashcommand's data is likely to be far more accurate than anything else you would be seeing.
225° EOT @ 70MPH would be about average with a stock radiator.
225° Coolant is pretty hot. If your Oil Cooler is in good shape, that's still 235+° EOT.
235° Coolant (245+° EOT) is probably an accident waiting to happen.
The radiators are a little thin. Even the 8500GVW radiator only had a 1-7/16" thick core from the factory.
Many cores were only 1".
And, as I stated above, over time they fill up with dirt.
At 10 years, I removed my 1-7/16" core radiator, pressure washed it, and painted it.
It helped a lot. The area directly behind the fan was absolutely full of dirt.
Before I pressure washed it, you couldn't get light through that area. After I pressure washed it, you could read through it.
I'm not kidding when I tell you those radiators fill up with crud.
At 15 years, I replaced my radiator with a 2-1/4" core. It helped tremendously with interstate speeds and big, wind-catching loads.
Here's a tip for anyone with Dashcommand or Torque:
Check your Oil Temp (EOT). It's more important than the Coolant Temp (ECT).
If the Engine Oil Temp is up around 225*, the coolant temp should be between 210 and 215 degrees.
If it's more than 15 degrees different (at 225* EOT), you have problems in your Oil Cooler.
But, that number is relative. If your Oil Temp is only 195*, EXPECT the Coolant to at least 25* lower than EOT...
If your EOT is routinely going over 230°, you have a problem.
