80 series very hot

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My 1993 occasionally stays very hot after I park it. Hot to the touch for 2 hours
Fan works
Heat works
No play on water pump
No leaks
No implications on dash.
Any guidance would help.
 
Have you noticed a significant reduction in performance (lack of power)
 
Like the hood stays hot? Or the engine? We need more details here. Also it would be relevant to post your climate and how you use the vehicle because these are all relevant to your question.

That being said there is a lot of metal to soak up a lot of heat on an 80 series....
 
Like the hood stays hot? Or the engine? We need more details here. Also it would be relevant to post your climate and how you use the vehicle because these are all relevant to your question.

That being said there is a lot of metal to soak up a lot of heat on an 80 series....
It was 80 degrees today hood was hot and so were the fenders.
The battery tender was soft 2 hrs later it is mounted by the charcoal filter.
I took it the beach today ran A/C
It was fine.
 
Does taking it to the beach include driving in sand. Driving in sand works the engine hard and will definitely get things heated up.

The egr is also by the charcoal canister. If the truck is not overheating than I am betting everything is good.

Does the rig still have a hood pad?
 
Does taking it to the beach include driving in sand. Driving in sand works the engine hard and will definitely get things heated up.

The egr is also by the charcoal canister. If the truck is not overheating than I am betting everything is good.

Does the rig still have a hood pad?
Yes it does have a hood pad.
 
My 1993 occasionally stays very hot after I park it. Hot to the touch for 2 hours
Fan works
Heat works
No play on water pump
No leaks
No implications on dash.
Any guidance would help.
Define "hot to the touch".

Engines operate at 185°F, which is definitely hot to the touch.

Water heaters are typically set to a maximum temperature of 125° F or a person may experience 2nd degree burns from the water.

Check the temps with an infrared gun if you are concerned.

The higher the ambient temperature, the slower the rate of change (cooling) will be experienced.

Sitting in the direct sun will cause a hood and fender to be "hot to the touch" on a dark vehicle.
 
Our 80 and our LX are both very efficient ‘garage heaters’.
 
My 1993 occasionally stays very hot after I park it. Hot to the touch for 2 hours
Fan works
Heat works
No play on water pump
No leaks
No implications on dash.
Any guidance would help.
I have this problem with one of my 80s. After replacing a blown headgasket, and several other items of indeterminate age, everything seemed to be OK, but the hood and fenders were too hot to keep your hand on after it had been driven for any length of time. The key data point was that this only happened when I drove in the mountains, and the transmission had been slipping (shifting later than the shift pattern, but still within drivable limits) before the blown headgasket.

In my case, I believe the worn transmission (I'm betting on clutch disks) is heating the coolant to the point that the fan can't keep up with it. The transmission cooling circuit runs from the transmission, to the lower radiator tank, and then to the transmission cooler, before returning. This means that a hot transmission will result in a hot engine, if the cooling circuit can't keep up.

If your transmission isn't shifting properly, especially from start under load, this could be at least part of your problem. It's important to thoroughly validate the function of the cooling circuit first, though.

I know my engine cooling circuit is functioning properly, because I'm the one who cleaned it and replaced all the parts. This leaves only the transmission as a source of heat. This 80 is a '95 model, so I have independent temperature validation, and I know that when the hood and fenders are hot, the engine is above normal operating temperature.

It's going to be difficult for you to independently verify the engine temperature while driving, since you don't have an OBDII port. Troubleshooting your problem, I would start at the thermostat, since a closed valve will cause overheating. Validate the part in a pan of water, as per the FSM, before just throwing a new one at the problem. If it's not malfunctioning, and you replace it anyway, you'll never know what the problem is. In my case, I know the valve works, because I tested it before installing it.

If your thermostat is good, the next suspect is the fan clutch, which should be tested too. If your water pump isn't leaking, it's likely not the problem. If both the thermostat and fan clutch are operating properly, you have to have your radiator flow and pressure tested. That's really all there is to the cooling circuit.
 
I have this problem with one of my 80s. After replacing a blown headgasket, and several other items of indeterminate age, everything seemed to be OK, but the hood and fenders were too hot to keep your hand on after it had been driven for any length of time. The key data point was that this only happened when I drove in the mountains, and the transmission had been slipping (shifting later than the shift pattern, but still within drivable limits) before the blown headgasket.

In my case, I believe the worn transmission (I'm betting on clutch disks) is heating the coolant to the point that the fan can't keep up with it. The transmission cooling circuit runs from the transmission, to the lower radiator tank, and then to the transmission cooler, before returning. This means that a hot transmission will result in a hot engine, if the cooling circuit can't keep up.

If your transmission isn't shifting properly, especially from start under load, this could be at least part of your problem. It's important to thoroughly validate the function of the cooling circuit first, though.

I know my engine cooling circuit is functioning properly, because I'm the one who cleaned it and replaced all the parts. This leaves only the transmission as a source of heat. This 80 is a '95 model, so I have independent temperature validation, and I know that when the hood and fenders are hot, the engine is above normal operating temperature.

It's going to be difficult for you to independently verify the engine temperature while driving, since you don't have an OBDII port. Troubleshooting your problem, I would start at the thermostat, since a closed valve will cause overheating. Validate the part in a pan of water, as per the FSM, before just throwing a new one at the problem. If it's not malfunctioning, and you replace it anyway, you'll never know what the problem is. In my case, I know the valve works, because I tested it before installing it.

If your thermostat is good, the next suspect is the fan clutch, which should be tested too. If your water pump isn't leaking, it's likely not the problem. If both the thermostat and fan clutch are operating properly, you have to have your radiator flow and pressure tested. That's really all there is to the cooling circuit.
Great answer,
Water pump and thermostat are fresh!
Is this a sign transmission is failing?
Heat (interior) blows at 118°
In September I felt slipping in transmission and changed fluid all has worked good since then until a 84° DAY yesterday.
Not sure how to check fan clutch.
 
Great answer,
Water pump and thermostat are fresh!
Is this a sign transmission is failing?
Heat (interior) blows at 118°
In September I felt slipping in transmission and changed fluid all has worked good since then until a 84° DAY yesterday.
Not sure how to check fan clutch.
Does your engine temp gauge ever go above halfway?
 
Great answer,
Water pump and thermostat are fresh!
Is this a sign transmission is failing?
Heat (interior) blows at 118°
In September I felt slipping in transmission and changed fluid all has worked good since then until a 84° DAY yesterday.
Not sure how to check fan clutch
@landtank has the definitive thread on everything fan clutch.

I can't know for sure, because I haven't ridden in the truck, but if the shift pattern has changed under load such that the shift points are later than specified in the FSM, yes, your clutches are probably wearing/worn.

There is a stall test for the transmission in the driveline section of the FSM.

I won't be able to say definitively until I break open the failing A343F in my 80 this summer, but I've narrowed my overheating problem down as well as I can to only one heat source, and that's the transmission cooler circuit. It may be the torque converter, or the clutches, or a combination of those, or other, items, but I'm comfortable with my analysis.

FWIW, my temp gauge never gets above the midpoint, even though my BT dongle-scanner tells me the engine is well above what I would expect normal operating temperature to be. IMHO, that temp gauge is as useful as an idiot light, even with the @RavenTai temp gauge mod.
 
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@mtlandcruiser Are you new with your 80 or is this a recent development in your years of fender and hood digital examinations or did you just recently decide to put a hand on the truck after shut down? It’s hot to the touch two hours later during a sunny summer day or on a cloudy winter day? What color is your paint?

I’m trying to establish a basis here. Before jumping to conclusions that will deplete your bank account it would be prudent to use an infrared thermometer to verify transmission and engine temps immediately following a session of normal driving with the engine still running.
 
You can’t go by the temp gauge in these trucks !!
They have a dead spot and don’t start to go past med mark tell it’s to late.
Does the AC cut out that happens at 226 degrees.
The 93-94 have a very stout transmission I have never heard of one going out !
 

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