Coolant flush additives?

[G Men 08]

Going through the process of flushing the engine to rid it of the mixed coolant that was in there from the previous owner(s) no clue how long it has been mixed.

I am 7 gallons of 100 percent distilled water into this and although the water is coming out more clear than the previous time, I am still getting a light brown color coming out. Should I use an additive to help clean the engine, maybe let it set over night to really soak in and clean? Or keep doing what I am doing until clear?


Right now I am adding 100% distilled water to the engine, letting it idle until operating temp, topping off a few times and bleeding the air from the system via heater core. Then holding a 2k rpm idle for a few minutes, removing the lower radiator hose, and the last 2 cycles I have pulled the block drain plug...

[a4kamila6]

CRC i believe its called works and doesnt corrode the aluminum, now what it does to all the hoses and other fittings, no clue, but its been around for a while. Whichever cleaner you choose, make sure its safe for aluminum.

[430hps4]

I'm a big fan of BG Products. Maybe look into their coolant flush 2pk. Can usually find around $30 shipped.

[G Men 08]

Here are a few pictures of the process, in order from left to right. First gallon is what came out of the engine originally, the following are the distilled water flushes.

First picture here is before all of the sediments settled down



Note the 2 liter bottle difference.

[a4kamila6]

You pumped the distilled water through the heater core hot or cold?

[G Men 08]

Pure distilled water through the entire engine from cold start to operating temp, with heat on max.

[a4kamila6]

Ahh that works too

[bpark1210]

That's freakin crazy! Any idea what the sediments consist of?

[Chris_s1]

Dammit.. I have my distilled water sitting there begging me to do this and I just haven't yet.... seems like such a long process lol

[BasicA6]

do you have w write up of how you did this?

[glennda5id]

This process will go a lot faster if you pull the engine block drain plug when draining.

There is a flush chemical on the market called ThoroFlush. It is very strong and works very well. It makes the Prestone stuff look and taste like candy.

[a4kamila6]

This process will go a lot faster if you pull the engine block drain plug when draining.

There is a flush chemical on the market called ThoroFlush. It is very strong and works very well. It makes the Prestone stuff look and taste like candy.

Taste like candy lol.