Improving the cooling on our TJs

Performance radiator shows the later model tj heater core back in stock.

https://shop.performanceradiator.co...ath=1_22310_22822_22874_22876&product_id=8045

1659456440323.png


it shows in stock on the main page but then it's out of stock once it's in the cart.

1659456362602.png
 
https://thebrassworks.net/products/2002-2006-jeep-wrangler-heater-core?_pos=5&_sid=2cbbcf789&_ss=r

I have one of these in order … I really like the idea of hand made, all metal construction. Made in USA too.

If this brass heater core will last as long as the heater core in my old corvette (that was not made with care and attention to detail) I’ll be very happy … BTW that corvette is 42 years old. Also still has the original Harrison Brass Radiator.

holy moly, that's a pricey one. but if it lasts, I suppose it's worth it. I do like the idea of it not being aluminum. Aluminum is the least noble of all the metals in the cooling system and will corrode faster than any of the other components. It's a fine material for an easily replaced radiator, or a cylinder head that has wall thickness to be able to lose a lifetime of metal to corrosion...but a heater core isn't the place.
 
https://thebrassworks.net/products/2002-2006-jeep-wrangler-heater-core?_pos=5&_sid=2cbbcf789&_ss=r

I have one of these in order … I really like the idea of hand made, all metal construction. Made in USA too.

If this brass heater core will last as long as the heater core in my old corvette (that was not made with care and attention to detail) I’ll be very happy … BTW that corvette is 42 years old. Also still has the original Harrison Brass Radiator.

You already use their cores? I am thinking about ordering one as well. This is a complicated job to replace the heater core, don’t want to do it twice.
I don’t mind paying more for us made product, as it seems to be a small custom business.
 
Last edited:
When folks told me that I might need a flush, I initially ran 3 sessions on blue devil. It didn’t really change a lot.
Now i am running thermocure. This is my first run, 3 days in total, with like 3 hours of running in total. The mix of distilled water and thermocure looks like this.
Thermocure responds to rust, and it seems like I had a plenty of it. Just look at how black it became.

51DC690F-DB56-4D73-AB6B-1B24C3F744B5.jpeg
 
  • Like
Reactions: L J
Put 3 oz of water soluble oil in the radiator.

You will not have a rust problem in your cooling system again.

Thermocure looks like the water I would see after pouring muriatic acid and water into a barrel.

Then running it thur raw water cooled marine engines to knock out rust and salt.
 
You already use their cores? I am thinking about ordering one as well. This is a complicated job to replace the heater core, don’t want to do it twice.
I don’t mind paying more for us made product, as it seems to be a small custom business.

Not yet, still being built, I guess … seems like a custom business in Paulo Verdes Estates, very fancy area just north of Long Beach in California. Oddly the PayPal account I paid had FlowKooler in the email address …
 
Finished the first session of thermocure.
Kept it in for almost 5 days (didn’t have time to drain).
Mix of distilled water and thermocure simply turned black.

24BD9654-A42F-4FEA-A492-4B5350D31C17.jpeg
 
I need to hear more about this water soluble oil...
Do you know of anyone who has block rusting issues who has maintained their system appropriately by not leaving the coolant in there past the life span of the anti-corrosion additive package found in all quality coolants? I know that I for one would highly appreciate spending less time on the phone and less time answering emails due to the seemingly impossible task of flushing brake fluid at the recommended service interval of 2 years. If folks would do that, we would have far fewer damaged calipers, pads and rotors with the occasional unit bearing tossed in for good measure. ;)
 
In case anyone is wondering, ZEREX G-05 lifespan is "5 year/150,000 mile". Most other coolants are likely 3 year.
 
Do you know of anyone who has block rusting issues who has maintained their system appropriately by not leaving the coolant in there past the life span of the anti-corrosion additive package found in all quality coolants? I know that I for one would highly appreciate spending less time on the phone and less time answering emails due to the seemingly impossible task of flushing brake fluid at the recommended service interval of 2 years. If folks would do that, we would have far fewer damaged calipers, pads and rotors with the occasional unit bearing tossed in for good measure. ;)

Nope, not a one! It's crazy what some preventative maintenance will do and how many fewer snake oil products are needed to address the problems related to poor maintenance/service intervals...
 
I need to hear more about this water soluble oil...

Sounds like an oxymoron to me … I believe water wetter helps, but not to run cooler, rather reduce hot spots along the block and head. Used by friends with turbo drag cars.

But our motors are far from stressed, even full throttle climbing a hill. I literally don’t understand why we run as hot as we do. We do have tiny radiators. But up to snuff they do the job, just barely, not a lot of overhead in our system …

I’m a huge fan of cleaning the water jackets. In my experience I’ve seen sand even come out! My guess is casting sand.
 
  • Like
Reactions: pc1p
Water Soluble Oil is a surfactant.

It bonds the water to the surface of the entire cooling system.

This allows heat to better transfer from the surface to the water, then out to the radiator.

Typical results are a 15 to 20 degrees drop in coolant temp.

Added benefit is the lubrication of water pump seals.

I have been using it for decades.
 
Water Soluble Oil is a surfactant.

It bonds the water to the surface of the entire cooling system.

This allows heat to better transfer from the surface to the water, then out to the radiator.

Typical results are a 15 to 20 degrees drop in coolant temp.

Added benefit is the lubrication of water pump seals.

I have been using it for decades.

Oh! Surfactant … I didn’t realize they were synonymous … it does work, breaks down the surface tension of the coolant and allows the water to better “hug” the material for better heat transfer.