How hot is too hot?

[mpmitch1]

I have a l5740 that runs one bar past the middle whenever its under load or working. I have

flushed the coolant and replaced with new green coolant 50/50 plus a coolant additive,
used an air compressor to thoroughly clean radiator fins, then wash the radiator with water hose. I have also, tightened the fan belt. Operating temperature outside is currently 95 degrees and I'm running rotella T6 engine oil. Temp sensor does return to the middle after idling for a few minutes. Any ideas?

 

[Mowbizz]

Run it!

 

[jimh406]

If it isn't climbing, my guess is it's ok. But, I'd call the service department for your dealer if this is something new.

Possibly a thermostat issue.

 

[The Evil Twin]

Is it a new thing? As in, new since the last time it was this hot? Summer heat and humidity take a toll on any cooling system. Hot humid air is less dense and contains less O2 per cubic foot. So to do the same work it takes more energy. That's why Chassis dynos are corrected for temp, pressure and humidity.

 

[imnukensc]

Sounds perfectly fine to me.

 

[TheOldHokie]

Sounds perfectly fine to me.

And people wonder why modern vehicles do not have gauges.....

Dan

 

[The Evil Twin]

And people wonder why modern vehicles do not have gauges.....

Dan

This is true. My truck does, but I don't worry too much till a warning pops up. Climbing grades with coolant at 230 and oil at 240 and I don't see any warnings.

 

[RBsingl]

And people wonder why modern vehicles do not have gauges.....

Dan

Or dummied down gauges. The oil pressure gauge on my 2018 GMC Denali diesel pickup is true and responsive but even though the coolant temperature gauge markings would lead you to believe it provides a linear readout from 160 to 260 degrees, once warmed up it will indicate 210 even with a +/- 10 degree variance in temperature. Somewhat surprisingly, when set to tow/haul mode the Allison automatic fluid temperature replaces the voltage display in the instrument panel and unlike the engine coolant temp it provides an accurate real time display that tracks with OBD II reported data.

At least my Corvette C7 Z06 provides true reading responsive gauges even though they are via a LCD panel.

Equipment should have calibrated gauges that respond in real time, not idiot lights or gauges that are basically "analog idiot lights".

Rodger

 

[NCL4701]

Problem with idiot lights is most of the time with a gasoline car engine with an aluminum head the light is simply advising you need a top end job at minimum. Have saved engines several times when the gauge started climbing and I could back off, remove a stuck thermostat until I could get a replacement, turn the heat on full blast to help the radiator, clean the radiator, etc. Gauges have saved me tons of money over the years.

And yes, engines normally run hotter in hot weather. Used to have to plow at night in my father’s old Ford because it would over heat on hot days. Watching the gauges is necessary but if staying out of the danger zone and isn’t climbing should be fine.

 

[TheOldHokie]

Or dummied down gauges. The oil pressure gauge on my 2018 GMC Denali diesel pickup is true and responsive but even though the coolant temperature gauge markings would lead you to believe it provides a linear readout from 160 to 260 degrees, once warmed up it will indicate 210 even with a +/- 10 degree variance in temperature. Somewhat surprisingly, when set to tow/haul mode the Allison automatic fluid temperature replaces the voltage display in the instrument panel and unlike the engine coolant temp it provides an accurate real time display that tracks with OBD II reported data.

At least my Corvette C7 Z06 provides true reading responsive gauges even though they are via a LCD panel.

Equipment should have calibrated gauges that respond in real time, not idiot lights or gauges that are basically "analog idiot lights".

Rodger

View attachment 85083 View attachment 85084

My truck has a coolant temp, voltmeter, and oil pressure gasuge. The oil pressure gauge has two positions - zero and middle. Glorifief idiot light.

My BMW has an oil temp gauge and nothing else. The ECM has three levels of coolant temp warnings that appear on the LCD:

Caution - running high
Warning - nearly over temp
Shutdown - over temp and you have just enough time to pull off the road before engine shuts off

BMW idea works for me.

Dan

 

[Dieseldonato]

My truck has a coolant temp, voltmeter, and oil pressure gasuge. The oil pressure gauge has two positions - zero and middle. Glorifief idiot light.

My BMW has an oil temp gauge and nothing else. The ECM has three levels of coolant temp warnings that appear on the LCD:

Caution - running high
Warning - nearly over temp
Shutdown - over temp and you have just enough time to pull off the road before engine shuts off

BMW idea works for me.

Dan

Right after I bought my expedition I blew a heater hose on the interstate. Before I could get over and into a pull off, it started missing like crazy. Water temp gauge was OK, but had a red idiot light on the dash. Thought for sure I blew a head gasket. Turns out it turned my v8 into a 4 cylinder to de-rate the engine. That light was, it is time to get over right now...

 

[mpmitch1]

This is my first summer with it, so I don't know it's history. My 3240 did the same thing when pulling the same heavy disc. Additionally the air filter is clean. I guess my normal is a little hot but not too hot?

Is it a new thing? As in, new since the last time it was this hot? Summer heat and humidity take a toll on any cooling system. Hot humid air is less dense and contains less O2 per cubic foot. So to do the same work it takes more energy. That's why Chassis dynos are corrected for temp, pressure and humidity.

Firs

 

[Pawnee]

I had a car that ran in the red on the temp. gauge but I measured the coolant temp and found it to be normal so I took the cover off and bent the needle to the middle.
That is how you calibrate a Peugeot temperature gauge.

 

[GreensvilleJay]

'67 Mustang with big 6,never EVER got 'hot'. even in mid of summer, only 'mild' and that's AFTER we removed the fan blade. Man I miss that car....

 

[ferguson]

just get harber freight heat temp gun to check / have a good fluk son got a HF with in a deg. of my fluk / there like $12

 

[Pawnee]

just get harber freight heat temp gun to check / have a good fluk son got a HF with in a deg. of my fluk / there like $12

Yah but if it works its a Fluke

 

[skeets]

My Harley dont have any gauge,, GAUGES we dont got no gauges,,, we dont need no stinkin gauges

 

[Pawnee]

My Harley dont have any gauge,, GAUGES we dont got no gauges,,, we dont need no stinkin gauges

Your Harley ain't got no coolant neither so she don't need no gauge.

 

[GreensvilleJay]

jes needs a diaper underneth to keep the oil from pollutin the hiways...
and a muffler

 

[The Evil Twin]

This is my first summer with it, so I don't know it's history. My 3240 did the same thing when pulling the same heavy disc. Additionally the air filter is clean. I guess my normal is a little hot but not too hot?

Firs

Yeah, I wouldn't worry. Things are going to run warmer when it's hot. The important thing is that it cooled back down when you took the load off. That means there is hear transfer. If it didn't there would be a problem somewhere.
The only thing I didn't see that you did was tedt the radiator cap. It is an often overlooked part of cooling system troubleshooting. If the cap is not holding pressure (or not holding enough pressure) cooling system efficiency drops. If you can't find a place to test it, a new one isn't expensive.