So much diag and parts replacement - still overheating

[Maryserv]

Has your mechanic done an HC test. It could be a head gasket, typically you will start popping hoses, gaskets, and even the heater core if it's bad enough. Possible that a minor leak into the cooling system from a head gasket could cause over heating.. This is what shops use to test.
Amazon product ASIN B06VVBSFTF
I'm not sure my link doesn't show.. Go on Amazon and search "block tester"

I have block tested with new fluid, yes.

 

[Motorhogman]

I have block tested with new fluid, yes.

Then I'd be looking somewhere besides a head gasket. You covered all the bases if I recall. I'd have to go back and read from the start. Can't right now. Have to shut down my computer stuff, severe thunderstorms starting up.

 

[Maryserv]

Then I'd be looking somewhere besides a head gasket. You covered all the bases if I recall. I'd have to go back and read from the start. Can't right now. Have to shut down my computer stuff, severe thunderstorms starting up.

Bragging! I want a thunderstorm!

 

[Maryserv]

Today I drove without using the A/C at all. I did a freeway trip that slowed to 40 mph as I neared home. I did not have the overheat issues as I’ve been having when I am running the a/C.

 

[D Hook]

I've had the exact same problem; no A/C, no problem; turn on A/C get overheated. Happens on highway driving and city streets, exactly as you described. Took it to my regular mechanic and he recommends loosening the radiator to get in between the radiator and condensor to really get a good clean and then a flush and fill. So I plan on having him do this next time I go in for oil change. Following this thread for any other suggestion.

 

[Maryserv]

I've had the exact same problem; no A/C, no problem; turn on A/C get overheated. Happens on highway driving and city streets, exactly as you described. Took it to my regular mechanic and he recommends loosening the radiator to get in between the radiator and condensor to really get a good clean and then a flush and fill. So I plan on having him do this next time I go in for oil change. Following this thread for any other suggestion.

Cleaning the outside of the radiator?

 

[D Hook]

Cleaning between the A/C condensor and the radiator. He thought maybe there's an accumulation of stuff between the two. It's difficult to get the fins really cleaned well because the two are so close together. So not remove the radiator, just to loosen the radiator and give more space to get in there with stream of water.

 

[Turdle]

If you remove the radiator you may find a huge nest of leaves, lint, hair, mud ,dead insects or animals, and or old wasp nests blocking air flow.

 

[410Fortune]

Compressed air is good at cleaning out fins

This is why I suggested the entire cooling stack he inspected
The ac compressor and clutch should be inspected as well

 

[KillJoy]

I have block tested with new fluid, yes.

Reading through this and giving my 2 cents. When was the last time you have removed the oil filter, how did the oil look in the filter. I know this sounds strange but i have a 97 ranger 4.0 with the OHV, I cracked both heads in 3 places on each head, there were cracked between the intake valve and intake runners and cracked inside the intake runners. A chem test for a headgasket and cracked heads came back NEGATIVE but if you taped a rubber glove around the radiator cap and cranked the motor without starting the glove would inflate instantly. It only over heated sometimes and rarely even made it up to the top of the gauge. When I pulled the motor out and drained the oil pan all the oil in the pan looked perfectly normal, the oil that came out of the oil filter though was like pudding. Might not be your case but drain some of your coolant and wrap a glove over the cap and crank with injectors unplugged, if the glove inflates it has to do with the heads. If not, its something else

 

[410Fortune]

Good ol ohv

 

[KillJoy]

Good ol ohv

I was in highschool when this happened going to a trade school and drove it for a good 15-30k miles like that before it started to hate life

 

[Maryserv]

If you remove the radiator you may find a huge nest of leaves, lint, hair, mud ,dead insects or animals, and or old wasp nests blocking air flow.

Turdle, so you suggest pulling and cleaning, right? Just water at a medium pressure for the fins?

 

[Turdle]

You want to clean the fins of the condenser also. Walmart sells a spray foam cleaner, look for it near the ac units. The foam will clean off films to really improve efficiency.

Spray it on your radiator and condenser, let it work a while then spray clean with a garden hose.

 

[Turdle]

Frost king acf19 is the product I use. It brings dead window ac units back to new life.

 

[zadigadabop]

could it be trapped air in the cooling lines? Sorry if this was mentioned already.

 

[Maryserv]

Reporting back…definitely A/C related. I’ve been driving under various conditions without the a/c on and no overheating. I turned the a/c on for a short time yesterday afternoon and the temps went up. My thought is that I need to understand how the a/c is connected over all and can I test the functionality of the component while on the truck. What other questions should I be asking or considering?

 

[Motorhogman]

Reporting back…definitely A/C related. I’ve been driving under various conditions without the a/c on and no overheating. I turned the a/c on for a short time yesterday afternoon and the temps went up. My thought is that I need to understand how the a/c is connected over all and can I test the functionality of the component while on the truck. What other questions should I be asking or considering?

The only thing I see you haven't done is remove the radiator from the truck and take it to a professional radiator shop for testing and cleaning inside and out. The one thing that sticks in my mind is you said the inlet and outlet temps were the same.. They shouldn't be. Back in the day that would be a red flag. Even further back in the day just putting a hand on the core in different places was test feeling for cooler spots. Sometimes a cool spot would indicate the core was plugged in that area. Unlikely that can be done on a modern vehicle because you can't get a hand any where. LOL. Infrared temp tool maybe..

 

[410Fortune]

I have an older mini excavator
The cooling stack gets dirty quick causing heat up issues
I used a piece of brake line and made an air blow gun that can easily reach in between the oil cooler and radiator and clear out debris/mud/ dust

Sounds to me like:

Your ac compressor
Clutch is locked up / hard to turn causing drag

Or

The ac condenser is plugged with dirt /debris

Or

The cooling stack (radiator trans cooler ac condenser) is dirty and or plugged up w debris

 

[94Eddie]

I'll keep saying this.... your symptoms point to a bad, or partially clogged radiator. This is the only way having the AC being on would cause an overheating problem. When the AC is on, this creates a higher heat load on the cooling system. It is very likely that the added heat load coming from the AC condenser is more than the radiator can handle in its current state, which is likely it being partially clogged, cooling fins collapsed, dirt/bugs restricting airflow etc.