Improving the cooling on our TJs

Yup. The pump and thermostat had been replaced as well as the fan clutch.

The AutoZone rad was fine except in high-heat+ac or high-heat plus idle.

It never failed but I finally decided it was the weak link and that was correct

Why did you chose Koyorad? Specific recommendations that you got? At this point there are no Mopar radiators for auto TJ available, I have ordered one and the order got canceled because they no longer have stock.
 
Why did you chose Koyorad? Specific recommendations that you got? At this point there are no Mopar radiators for auto TJ available, I have ordered one and the order got canceled because they no longer have stock.

I had a shop do it when they were doing other work(steering gear box). It was the one they recommended and would warranty.
 
210-212° is perfectly normal. If it bothers you that much out a 180° thermostat in it, but 210° is the sweet spot.
 
We got that too. I was close to 220 but it’s nbd. Run a 180° and done.

Running 180 thermostat cannot be a solution. For sake of experiment, I even ran w/o a thermostat at all, it didnt change anything compared to running with thermostat.
Don’t want to be a boring engineer (which I am as a matter of fact), but you cannot cheat thermodynamics (but you can hack computer SW or HW :) )
The difference between 180F and 195F thermostats is just in a spot where the flow of coolant to radiator will start. The moment that Coolant reaches 210F, it does not matter whether the coolant started to flow at 180F or 195F.
Simple equation of how much heat engine generates per second, and how much radiator can dissipate in a same second.
 
Running 180 thermostat cannot be a solution. For sake of experiment, I even ran w/o a thermostat at all, it didnt change anything compared to running with thermostat.
Don’t want to be a boring engineer (which I am as a matter of fact), but you cannot cheat thermodynamics (but you can hack computer SW or HW :) )
The difference between 180F and 195F thermostats is just in a spot where the flow of coolant to radiator will start. The moment that Coolant reaches 210F, it does not matter whether the coolant started to flow at 180F or 195F.
Simple equation of how much heat engine generates per second, and how much radiator can dissipate in a same second.

To be an engineer there should be a prerequisite as a mechanic which I am a master mechanic! So cool. Have you checked you head? For cracks if you have done everything and all is in spec I would look else where for the issue. Even as simple as a bubble of air. I’ve installed a barbed fitting on upper hose with a bleed screw. Works great.
 
We got that too. I was close to 220 but it’s nbd. Run a 180° and done.

That's not how it works, at all. The thermostat controls the low side by opening to let flow into the radiator. The radiator and the efficiency thereof (coupled with flow rate and air movement) are what controls the high side. Letting the coolant into the radiator sooner at a lower temperature does nothing to improve the high side if it isn't doing its job.
 
To be an engineer there should be a prerequisite as a mechanic which I am a master mechanic! So cool. Have you checked you head? For cracks if you have done everything and all is in spec I would look else where for the issue. Even as simple as a bubble of air. I’ve installed a barbed fitting on upper hose with a bleed screw. Works great.

Have it your way, I rebuilt two engines on my own and spent 5 years mechanic-ing on my way to an engineering degree followed by 15 years of heat transfer and thermodynamics work...the 180 thermostat doesn't set your ceiling, only your floor.

The heat rejected by the radiator has to equal the heat pulled out of the engine, and is (effectively) directly proportional to the temperature difference between coolant and air. Meaning the coolant will find the temperature at which heat in = heat out.
 
To be an engineer there should be a prerequisite as a mechanic which I am a master mechanic! So cool. Have you checked you head? For cracks if you have done everything and all is in spec I would look else where for the issue. Even as simple as a bubble of air. I’ve installed a barbed fitting on upper hose with a bleed screw. Works great.

I'd be very sad if I told someone I was a master mechanic and didn't understand how cooling systems worked.
 
Have it your way, I rebuilt two engines on my own and spent 5 years mechanic-ing on my way to an engineering degree followed by 15 years of heat transfer and thermodynamics work...the 180 thermostat doesn't set your ceiling, only your floor.

The heat rejected by the radiator has to equal the heat pulled out of the engine, and is (effectively) directly proportional to the temperature difference between coolant and air. Meaning the coolant will find the temperature at which heat in = heat out.

Do you happen to know how they achieve the bumpy texture on the inner wall of heat pipes to increase the surface area? I've seen it or something similar but not on the interior of a tube.
 
Do you happen to know how they achieve the bumpy texture on the inner wall of heat pipes to increase the surface area? I've seen it or something similar but not on the interior of a tube.

There's a lot of ways to do it, ours is mostly round tubing so it's done during the drawing or extrusion process and ends up looking like rifling in a firearm barrel. I might be able to answer more specifically if have a sample photo of something different.
 
Running 180 thermostat cannot be a solution. For sake of experiment, I even ran w/o a thermostat at all, it didnt change anything compared to running with thermostat.
The only thing running without will do is lower the operating temp of the engine IF you have enough capacity in the system to over cool it and the TJ actually does in stock form.
 
Do you happen to know how they achieve the bumpy texture on the inner wall of heat pipes to increase the surface area? I've seen it or something similar but not on the interior of a tube.

From what I've read, at least in computer applications, the heat pipes used have sintered metal bonded to the inside and they use it since it's very cost effective. But I'm no expert in this area and I'm curious to know what other methods are used in other applications that @freedom_in_4low may know more about.

https://www.1-act.com/resources/hea... heat pipes are one,pipes are made every day.

Sintered wick heat pipes are almost always cylindrical, although sintered vapor chamber wicks are also fabricated. During the heat pipe manufacturing, a (typically) cylindrical mandrel is inserted into the heat pipe, and held in place with endcaps. The sintered powder is poured into place in the annulus between the heat pipe and the mandrel. The system is then heated up to sinter the material together, and to the heat pipe wall. The mandrel has a coating to prevent the wick from sintering to it. After the heat pipe is cooled, the mandrel is pulled out of the heat pipe. The heat pipe endcaps and fill tube are added, and the heat pipe is charged with the working fluid.
 
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Ah. I'll be completely honest, I have no idea how they make that. I've seen a lot of different internal surface enhancements but that's a new one to me and I don't think that would be doable with the common manufacturing methods used for the tubing we use (which is 3/8-1"OD).
 
From what I've read, at least in computer applications, the heat pipes used have sintered metal bonded to the inside and they use it since it's very cost effective. But I'm no expert in this area and I'm curious to know what other methods are used in other applications that @freedom_in_4low may know more about.

[URL]https://www.1-act.com/resource... heat pipes are one,pipes are made every day.[/URL]

I don't know how they are made, but we used them in computers to move heat away from the CPU and GPU processor chips. The with/without difference is amazing.
https://www.amazon.com/dp/B09CL3RD82/?tag=wranglerorg-20
 
I don't know how they are made, but we used them in computers to move heat away from the CPU and GPU processor chips. The with/without difference is amazing.
https://www.amazon.com/dp/B09CL3RD82/?tag=wranglerorg-20

Yup, I'm aware that they are used 🙂

PXL_20220718_030656496.jpg
 
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