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Thermocure or CLR Radiator Flush

RonCSJ

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Getting ready to flush the coolant system on my 67 Charger 383. Has anyone used Thermocure or CLR Radiator Flush? Recommend, don’t recommend? Worked well or didn’t? One better than the other?

Thanks!

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I used CLR. Did it about 3 times, then followed up w Cascade dishwasher powder 3 times, then fresh water a couple times till it was perfectly clear. Then 50/50 distilled water n antifreeze. Plus 2 pints of the pink coolant additive. I was having serious cooling issues. Now it's hard to get my 496 over 165° when it in the 70's and never above 195° when its in the 100's with a 180° t-stat. I liked the CLR.
 
I used the Thermocure in 3 cars. It’s AWESOME! It will clean up the cruddiest cooling system with one use.

You must take out the block plugs and get all the antifreeze out first, nothing but water in the system. It’s one jug per 3 gallons of water. I left it in for several days and drove the car to get it warm. The instructions say to do this. Drain it all and fill with water a couple of times and then it comes out spotless at the end. Put in antifreeze. Be a brave soul and buy the 100% coolant and mix in the water yourself. You will save money doing this.

To get the plugs out of the block use a 6 point 9/16” socket, if they don’t come loos try tightening first. Is there is a layer of scale poke through it so it drains there. Rinse it out good, then fill with water, run car till hot. Drain again and then add thermocure. Use anti seize compound on them on final installation.

makes me want to go buy a case of it before it’s discontinued. Summit sells it.

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Thermocure is awesome. It WILL take a lot of rinsing. Good advice on the block plugs above.
 
I'm in the middle of Thermocuring my Dakota.

It's had chronic coolant rust issues for years.

I tried CLR last time but it didn't last, although I used "regular" CLR, which I'm normally a big fan of.

Be aware that the Thermocure will look like thick, light green gatorade in your overflow.

I've done 50 miles and one flush to clear.

Another flush coming up.

I will say it took less flushing to get to clear this time than any other time.
 
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I've used the smaller bottles of CLR before with good results, I just followed the directions like on the Thermocure bottle. Wash, rinse, repeat until clean. I've also have had good luck with the Prestone Super Flush following the same procedure as above. Good Luck
 
Prestone did absolutely nothing for mine.
 
While we;re on this subject.....

Is there an aluminum or more durable radiator neck spout like the one that comes with the Prestone flush and fill kit?

I've found those wear and lose their grip on the neck hole after about 6 uses.

I also extend mine with a section of small diameter garden hose so the coolant doesn't just go all over the front of the vehicle.
 
I did two rounds of Thermocure last year. On the second drain/rinse a nasty clay like goo came out of the block plugs that must have been old head gasket seal or similar crap. Like Demonic said you'll have to rinse a lot, or you'll smell it in the coolant for a while. Clean and clear now.

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4 month update on Thermocure.

I'm gonna rate this product "WOW"!

:thumbsup:

I've put about 200 miles on it since I put the Thermocure in and I've only flushed it twice.

Water is now clear. No more rust.
 
I hope you opened the heater valve and got that core flushed out good too???
 
Bypassed.

It's a 177K Dakota.

Almost a challenge to find one that's not.
 
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