Flushing Radiator with Tap Water

[Drew99GT]

Quicker and more thorough IMO.

 

[1sttruck]

If the cooling system has been neglected and a heavy flush is needed to gets chunks of rust and other stuff out then use tap water to flush and follow up with 50/50 as another flush, otherwise skip the tap water flush. Using 50/50 as a flush allows the flush to kind of 'buffer' the cooling system, taking the initial hit in the additives to counter corrosion and acidity, allowing the final 50/50 fill to start off fresh for the duration of the change interval. I change coolant every 30k miles or so in the cars, so using 50/50 is just another gallon of coolant at about $8 or so.

 

[pemdas]

If factories are using tap water and the antifreeze manufacturers are telling the consumer otherwise then what is wrong with this picure?

 

[1sttruck]

http://www.granlydiesel.dk/fileadmin/dok...Maintenance.htm

Section 9 - Water Quality Requirements

Cooling systems perform best with distilled or deionized water. If distilled or deionized water is not available, the quality of the water used must meet all the requirements listed below. Excessive levels of calcium and magnesium contribute to scaling problems, and excessive levels of chloride and sulfate cause cooling system corrosion. If water quality is unknown, it can be tested with the Fleetguard® Monitor C™ program or Water-Chek™ test strip. Water test results can also be obtained from local water utility departments. Test data must show the following elements, and the levels must not exceed the published limits for use in cooling systems.

Table 5 - Water Quality Requirements

Element Maximum Level Allowable
Calcium, Magnesium (Hardness) 170 ppm (as CaCO 3)
Chloride 40 ppm (as Cl)
Sulfate 100 ppm (as SO 4)

 

[shoz123]

If I use a flush chemical I leave it in for a hour or two while I drive ensuring very good circulation of the cleaner.

Then flush with distilled water and run at idle until the water is hot and circulating.

Then drain, add a gallon of 70/30 mix (mixed with distilled) while having a coolant hose that is at the top of the system unhooked. This will force more water out. Then top off with 50/50 mix (mixed with distilled).

FWIW I use to work for a large battery manufacturer and they used only deionized water when mixing their acid......

 

[Audi Junkie]

I figure the penalty of some minerals in the flush water is outweighed by the cleaning power of the hose flush. Refill and drive with some distilled water and drain if you REALLY want.