Coolant running over 210+ F in Phoenix

[AFei]

Hello friends,

I was trying to figure out if it's normal for my coolant constantly run over 210F under Phoenix sun, no matter if it's cruising at 70mph on highway. It's even higher at 220+ when climbing from steep hills at highway speed. The outside air temperature is above 105F...

My 04 LX470 has new fan clutch, new coolant (drained/filled with over 16 gallons of distilled water), new tees, new hoses, and almost new thermostat. I tried a brand new 3 rows all aluminum radiator and now the CSF radiator, but the temperature seems same. Thermostat doesn't matter as it's same high temperature even without thermostat installed.

Anything I missed to get the coolant back to range?

 

[AFei]

 

[BullElk]

Defintely too high. Your A/C will turn off at 220* to prevent overheating. Perhaps you didn't burp the system successfully and have air in system.

 

[AFei]

Defintely too high. Your A/C will turn off at 220* to prevent overheating. Perhaps you didn't burp the system successfully and have air in system.

AC seems working fine, even it shows over 220. Have squeezed the upper hose lots of time for burping, with full heating.

One thing I'm waiting for part is the ECT sensor...

 

[suprarx7nut]

That is definitely not normal. I had my 100 in Phoenix for a couple years. 120F ambient temp, 190F coolant temp.

213 is boiling water. Do you have coolant in there or straight water?

Something's definitely amiss. Hopefully just a temp sensor, but I've never seen those fail in a way that would just show a little high. They're typically obviously wrong by a LOT or they're very accurate.

Does it run cooler if you crank the heat on high for a few minutes?

 

[Bisho]

Pink coolant boiling point is 226degF. How old is your water pump? How clean is your condenser, given you have a new radiator? Is your fan clutch engaging?

I've noticed on the forums that "normal" varies from truck to truck, so it wouldn't surprise me there are variations in the temp sensors. Normal for my 2000 100 in Texas would be 203-208 at 105deg and 70 mph. At 95 it starts to drop into the high 190s, and in the 80s and below the low 190s. In the CO mountains I've seen it get up to 215, but its working pretty had there. You definitely learn to put the transmission in a lower gear when you pay attention to transmission temps as well. By the way, all of this is with a rebuilt cooling system, although my radiator is 10 years old, its clean as a whistle, so I don't think changing it would do anything. My new Aisin fan clutch rarely ever engages.

My 07 LX, with possibly original thermostat, fa clutch and radiator (230k), runs about 5 degrees cooler, and its fan clutch starts to engage regularly when the outside temp gets to 105.

The LC is working harder to get the same performance (built and 4 speed, vs factory original and 5 speed), so maybe that's all the difference. Living in a hot climate also has an impact, as everything is heat soaked before you even get the truck started.

All that said, it does seem like you're running 5-10 deg hot.

 

[OEMGUY0720]

When was the last time you serviced/replaced your thermostat? If the temperature goes up as you go faster (higher rpm) or climbing uphill sections, that sounds like a water pump/thermostat issue to me. Could also be the coolant is not circulating effectively in the system due to a blockage or air pockets in the system. I would also run a head gasket leak test in the coolant.

 

[gil12]

Id check the concentration of the fluid after flushing and refilling. Im uncertain if these are accurate, but this is what I had in mind.

https://www.autozone.com/heating-and-cooling/antifreeze-coolant-tester/p/peak-antifreeze-and-coolant-tester/525881_0_0?cmpid=LIA:US:EN:AD:NL:1000000:HRD:19489353553&&CATARGETID=120054150001290089&CADevice=m&gad_source=1&gclid=CjwKCAjwodC2BhAHEiwAE67hJB8g3HrpgmbCxBizl5jl5wYsrJBfwF5GKGJ1OQxlp7h3O-altk07VRoCOUAQAvD_BwE&gclsrc=aw.ds

 

[newbielx470]

Just out of curiosity, does your dashboard coolant temp meter still stay right below the middle, or is it a bit higher toward the "H"? I know that sensor is not accurate and doesn't show high until it's really high temp, but want to see if it's showing at least something abnormal in your case of higher than normal temp.

 

[Patron100LC]

Radiator cap? Today I replaced my wife’s RXs radiator cap, it disintegrated on its own. Luckily got a Toyota dealer near by..
$20 peace of mind.

 

[AFei]

Thanks for all the replies. Just back from a nearby trail.

On trail, it runs cooler at around 190. It's hotter at higher speed.

Thermostat should not be the cause, as it's not even installed when first noticed the issue, although it's about 20K miles old. Water pump was also replaced at about 20K miles ago.

Fan clutch is brand new. It does engage.

Radiator cap is new with the radiator.

After drained water from all 3 drains, I filled and drained with actual pink coolant twice.

I did noticed it drained pretty slow from both engine block drains..

Dashboard gauges quit working, thanks Lexus for the quality. Also, I believe dashboard temperature gauge has its own sensor.

 

[Patron100LC]

Any stuff in front of the radiator? Bumper, lights or non oem grill that might be blocking air flow?
Condition of ac condenser? Maybe something stuck inside your grill that you missed..

Fuel flow restriction creates a lean high speed? Spark plugs not gapped properly? Vacuum leak?

I’d start with h the cheapest, clean condenser with a coil cleaner foam, triple check coolant level after driving for a few minutes with all heaters on and after parking nose up all night, replace cap with oem, remove stuff from the front to test air restricts, replace fuel filter, clean MAF, smoke for vacuum, test head gaskets with a leak down test, then go expensive and start throwing parts at it because that’s what we do.

 

[nissanh]

Did you install an OEM thermostat, how about the fan clutch? oem or aisin?
Did you clean the AC condenser fins and remove any debris?

 

[azusa]

Any stuff in front of the radiator? Bumper, lights or non oem grill that might be blocking air flow?
Condition of ac condenser? Maybe something stuck inside your grill that you missed..

Fuel flow restriction creates a lean high speed? Spark plugs not gapped properly? Vacuum leak?

I’d start with h the cheapest, clean condenser with a coil cleaner foam, triple check coolant level after driving for a few minutes with all heaters on and after parking nose up all night, replace cap with oem, remove stuff from the front to test air restricts, replace fuel filter, clean MAF, smoke for vacuum, test head gaskets with a leak down test, then go expensive and start throwing parts at it because that’s what we do.

/\This is what I came here to say, I'll add a few things I didn't see, fan shroud and foam. I also installed foam all the way around The radiator when I was installing a new radiator.

 

[AFei]

Any stuff in front of the radiator? Bumper, lights or non oem grill that might be blocking air flow?
Condition of ac condenser? Maybe something stuck inside your grill that you missed..

Fuel flow restriction creates a lean high speed? Spark plugs not gapped properly? Vacuum leak?

I’d start with h the cheapest, clean condenser with a coil cleaner foam, triple check coolant level after driving for a few minutes with all heaters on and after parking nose up all night, replace cap with oem, remove stuff from the front to test air restricts, replace fuel filter, clean MAF, smoke for vacuum, test head gaskets with a leak down test, then go expensive and start throwing parts at it because that’s what we do.

I did install the Ironman bumper along with the Badland APEX winch, which certainly created changed or blocked the air flow. I wish I had compared the coolant temperature before and after the installation of bumper. I suspected the new bumper at the beginning, but it's too late to remove it for troubleshooting.

Condenser looks pretty clean. Just recently replaced the fuel filter and cleaned MAF. Also did the compression and leak down test not a long ago while troubleshooting the misfire. In fact, the head gaskets and cylinder heads on both sides were replaced.

BTW, how do you do the "smoke for vacuum" test?

 

[AFei]

I'll add a few things I didn't see, fan shroud and foam. I also installed foam all the way around The radiator when I was installing a new radiator.

Yeah, I did add the foam to top and both sides. No foam on bottom as it's what OE looks like.

 

[azusa]

You have a bumper you have a winch, this is why you're running cooler at slower speeds. Years ago had a customer with a Mazda Miata, long story short he had replaced engine, radiator and everything else on the cooling system. He kept overheating on the freeway, the fix was to move the front license plate away from the opening to the radiator. Solved his issue after he had spent $5,000. Basically your bumper and whatever else you have up front is deflecting the wind away from the radiator causing higher temperatures at higher speeds.

 

[Patron100LC]

Yeah, I did add the foam to top and both sides. No foam on bottom as it's what OE looks like.

Actually, there is a foam in the OEM bottom part of the radiator, it's glued to the skid and rotten for sure..
But I don't believe that that little foam will put your temps 10-20deg higher than they should be at speed. There has to be another issue, Maybe the bumper and winch blocking, not sure if anyone else that have an aftermarket bumper experiences that, I mean these bumpers have been in use for years in extreme climates all over the world.. I have the torque app, live in south FL and at 93-94 deg ambient the temp is stuck at 186, doesn't move from there regardless of speed. But, I'm stock..
Also, it Can be that your coolant temp sensor is wonky..

edited to add, smoke test is done with a smoke machine, the cheap ones just create smoke by burning baby oil through a small hose, effective to find vacuum or emission system leaks if the leaks are big enough. The idea is that you fill the intake with smoke using a one of the many ports. The expensive machines should be more accurate and have pressured smoke to detect smaller leaks. As you might know, a vacuum leak Can make a lean mixture if undetected by the ECU, and cause higher temps including burning valves..
Not a pro, just a guy with a bunch of old school car magazines in my bathroom.

 

[dealmaker]

Defintely too high. Your A/C will turn off at 220* to prevent overheating. Perhaps you didn't burp the system successfully and have air in system.

Yeah, these can be a super PITA to burp. Has always been a multiple burp process for me over the course of a week.

 

[94SRUNNER]

Perhaps a vacuum bleeder will help to pull any air still hiding in the system.