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Whats the best way to do a coolant system flush on the 6.5?


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Nature Coast
Unless it is a high mineral added system for wet sleeve diesels like the above shown coolant “filter”. Many of the minerals that have to be added to stop local point heating, some people still use and that makes it conducive. Imo a mistake to use those additives and the evans. But some engine warranties mandate the tablet filters, especially heavy equipment. If it were me using evans and a new truck requiring I would do the garden hose flush to wear out the tablet before it went on.

Evans is like 80-90% polypropylene glycol and no water. It in itself isn’t electrically conductive but can become so with additives. Thermally conductive and electrically rates are 2 different items, but never far off- one of wideman frantz law iirc.

It’s kinda like water: pure H2O does not conduct electricity- all the stuff floating in it does. Thats a part of how distilled water helps in cooling systems. Keep the Evans pure and keep your radiator and heater core electrically isolated and you have no problems.
EVANS becomes acidic when more water than what is recommended is in a cooling system for diesel that's 3%.

No-Rosion is an interesting product to use with water here is an article that adds to my confusion with claims that tap water can be used. https://www.streetmusclemag.com/tech-stories/fuel-cooling-ignition-tech/antifreeze-chemistry/


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Rural Clifton, Illinois
We use citric acid to clean our well and water system, as well as other things

cleaning with citric acid 6 tablespoons to 4 cups/1 quart water

1/4 cup citric acid in filter housings

For the well we add - 4 cups mixed with 2 gallons hot water Not boiling - It just has to be warm enough for the powder to mix easily. 1. Liter of powder all poured in the well

4 cups = 2 lbs. Mixed with 2 gallons of water to clean filters

Allow to stand at least 1/2 hour longer is better.

We let it stand for about 8 hours and got good results

We have noticed a difference in strength of the Food grade Citric acid powder. One bag we bought required about double the amount to acquire the same results. Pretty cheap stuff off Amazon