Cooling system flush before overhaul question


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Fortzen1305

Fortzen1305

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OEM parts? I had bought non oem water pump and it had an internal crack thru a bolt hole. I knew it was leaking but could not locate it. Had to rent a system pressure check tool and pressurize the system to find it with the fan off. In the future, I will just add that step to the job prior to installing the fan. qslim is correct about the heater hoses. Dont forget them.
Yea, mopar radiator and water pump, stant/ motorad tstat, hayden fan clutch.
 
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Ericict

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Yea, mopar radiator and water pump, stant/ motorad tstat, hayden fan clutch.
There is a radiator shop in Denver. They can overhaul the radiator if you want to save some money. I did that here (Ks) and the complete job was $120.00. A whole lot cheaper than buying new.
 

zebra12

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Water will NOT get the years of crap out of your cooling system when flushing it.
View attachment 258381
Thermocure works.

Jugs on the right were after a Prestone flush, and the jugs on the left were after a Themocure flush. I did the Prestone flush first, then Thermocure.

thermocure.jpg
 

powderrrr

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So, part of me wants to ask this, but part of me doesn't (out of fear - ha!). But if I install the new Rad, water pump,
Stat, all hoses, etc. and then do the coolant flush, it seems less Fill/ Drain cycles would be required? IE, only the crud
from the block is getting cleaned out? I've also never done a coolant flush, so do chunks also come out or is it all broken-down sediment/ dirty water? Seems nothing should get stuck to the new parts, in the end?
 
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TJRick

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Thermocure works.

Jugs on the right were after a Prestone flush, and the jugs on the left were after a Themocure flush. I did the Prestone flush first, then Thermocure.

View attachment 258403

I have always used the Prestone flush, and the results look like the jugs on the right.

Tell me more about this Thermocure. I have never heard of it before. What does it do that the Prestone doesn't?

Why is the liquid inside the jugs on the left from the Thermocure so DARK?
 
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Rubicon88

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The PO of my Jeep changed the antifreeze every 3 years (20,000 miles). He was the only owner before I bought it and gave me every service record from the first oil change. I flushed it and still got rusty water coming out. 🤫
I'm not sure what you're saying here.
Maybe you have the only aluminum block and head 4.0 ever made..then yes that would be alarming.
If you've got iron like the rest of us in the mother loving Jeep world you certainly would get rusty colored water coming out during a flush until it clears up.

Unless I'm not understanding what you're saying.

****
Once the coolant is drained of course. If your coolant is rusty just sitting there before draining then it was never properly maintained and or the wrong ratio was used.
 
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BC Moto

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Anyone upgrade to a larger or oem size aluminum aftermarket radiator? Im thinking of doing so and changing the hoses at the same time and maybe switch to electric fans
 

Rubicon88

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Anyone upgrade to a larger or oem size aluminum aftermarket radiator? Im thinking of doing so and changing the hoses at the same time and maybe switch to electric fans
Why?
You running the Baja with a 700HP V8?

If your system is working properly and you've got a factory 4.0 your factory cooling system is plenty sufficient for the task at hand.
 
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BC Moto

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Why?
You running the Baja with a 700HP V8?

If your system is working properly and you've got a factory 4.0 your factory cooling system is plenty sufficient for the task at hand.
Because going low speeds creates heat and not moving doesnt allow sufficiant cooling thats why I ask. I just come from performance background and these are simple things to do to prevent problems. But yes later on with this build a LS swap is in its future
 
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Rubicon88

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Because going low speeds creates heat and not moving doesnt allow sufficiant cooling thats why I ask. I just come from performance background and these are simple things to do to prevent problems. But yes later on with this build a LS swap is in its future
I'd cross that bridge then.

If you're getting too warm now just crawling around then you've got issues. WP...thermostat etc..

Moreover i cringe when i read or hear electric fan. Why...
They're aftermarket and we've had several split radiators in the shop from electric fans not working proper.
Usually they weren't hooked up right by the installers but we've seen some defective too.

I've no doubt your mechanical prowess but for now I'd leave well enough alone...if it is in fact working well...enough.
 

BC Moto

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Well im new to my jeep and im trying to gather info and parts for the build. I havent gone out wheelin yet because the PO installed a lift kit and dropped the TC to ease the driveline, next weekend im installing the terrraflex sye kit and a adams driveshaft. If I can get a rear dana44 by then I would like to install that too! I have been daily criving it to find issues but nothing has come up but I thght the radiator and fans would be a good upgrade.
 

Rubicon88

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Well im new to my jeep and im trying to gather info and parts for the build. I havent gone out wheelin yet because the PO installed a lift kit and dropped the TC to ease the driveline, next weekend im installing the terrraflex sye kit and a adams driveshaft. If I can get a rear dana44 by then I would like to install that too! I have been daily criving it to find issues but nothing has come up but I thght the radiator and fans would be a good upgrade.
No...

I work on this stuff for a living and the TJ cooling system if in good working order is sufficient. Plenty!

If you venture in the swap realm ...pending what you swap that will be different.

But for now....

Go wheeling!!!!
 

BC Moto

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No...

I work on this stuff for a living and the TJ cooling system if in good working order is sufficient. Plenty!

If you venture in the swap realm ...pending what you swap that will be different.

But for now....

Go wheeling!!!!
Ok I will take your word on the cooling system for now just dont want the problems out there. As for a swap im thinking the LS 6.0 or 6.2 with a T56 and a atlas transfer case with dynatrac prorock axles is where i want to be.
 
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qslim

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Ok I will take your word on the cooling system for now just dont want the problems out there. As for a swap im thinking the LS 6.0 or 6.2 with a T56 and a atlas transfer case with dynatrac prorock axles is where i want to be.
If you do some more looking around on this forum you’ll see an overwhelming majority advocating for the factory cooling system. When it’s put together well & maintained it works like a champ. As for LS swap I don’t know, but for as long as you’re running your stock engine stay with the factory system.
 

Rubicon88

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Ok I will take your word on the cooling system for now just dont want the problems out there. As for a swap im thinking the LS 6.0 or 6.2 with a T56 and a atlas transfer case with dynatrac prorock axles is where i want to be.
It's your rig but I'd never use a T56 in a build like that.

There are much better choices. Much better.

That T-56 gets you a 2.9 1st gear. Somewhere thereof...

That's just not enough.
I understand you want an Atlas and that helps but....unless you're doing the banzai in mud you'll have to use low range for everything.
That limits your options.

If you're building a machine like that I'd get a SM465 or SM420...
No 5th gear however... and you might have an issue with that seeing that you want a 6 spd.

If you do then I'd put a NV4500...

5spd...5.6 1st gear...


The two i mentioned are short...
Have a 6.5 1st gear (the sm420 has a 7.1 1st gear..

Good luck in your endeavor
 

BC Moto

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Well thats why im here to gather parts and to see what others have used to complete my build and I appreciate all the im getting
 

zebra12

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I have always used the Prestone flush, and the results look like the jugs on the right.

Tell me more about this Thermocure. I have never heard of it before. What does it do that the Prestone doesn't?

Why is the liquid inside the jugs on the left from the Thermocure so DARK?
Thermocure is explained well on the Evapo-rust website and there are some good youtube videos on it too.