Like Saleen said... the proper way to flush a cooling system is to remove the T-Stat prior to the flush..this will allow proper circulation of flush material through-out the engine and heater core...which should be set to full heat during this flush...I would not use tap water either...distilled water only. after the flush is complete, I remove one side of the heater core hose and drain it also. You can also crank the motor for a second and if will expel even more of the flush ...

 

This is how I do it....I'll use your instructions but make modifications

-Drained the entire system.
-Replaced effected pieces.
-Closed pet ****.
-Filled with coolant flush and water.
-Ran to operating temp + 10 minutes.
-Turned truck off.
-Opened pet ****.
-Put water hose into coolant bottle.
-Ran water until clear liquid came out of pet ****.
-Closed pet ****.

Up to this point you're fine. Now you want to fill with only water, bring to operating temp (drive it don't just idle it). Drain and repeat a few times. Each time bringing it up to operating temp. Make sure the heater is on and hot air is blowing. The goal is to get out the old flush chemicals. I will do this like 4-5 times. It's a PITA but without a block drain what choice do you have.

-Filled radiator with coolant (not 50/50 premix)

Drive the truck around making sure everything gets mixed (again with heater on). Now you can test with coolant tester to see what your protection is. If it is low, add pure coolant, if it is high, add water. You may need to drain some mix off from the radiator to get more pure coolant in if you test low but have no room to add more coolant.

Once the mix is right, then for the next several weeks check the overflow bottle and keep topping it up with 50/50 premix until all the air is out of the system.

It's a lot easier just to forget using flush and drain the radiator and refill with premix every other year. You get about half of it changed but you're doing it often so this method works pretty well.

 

How do you drain the entire system ??
and what would the fan motor being on have to do with anything ??

 

You never drain the entire system but you leave fresh water in the block and undiluted coolant in the radiator which will mix.

Running the heater lets you know that the fluid in the heater core is circulating.

 

Was just wondering why you said in the first step..."drain the entire system"
agree to turn the selector **** to heat...but, the fan/blower don't do anything during the flush except blow across the core.

 

The OP said that, I just copied his steps to a point then started typing. His first step does not drain the system but I got what he was trying to do. Agreed the fan doesn't do anything but let you know the core is hot.

 

gotcha

 

"I'll drain a gallon out of the system and replace it with a 2nd gallon of concentrate"

Maybe my memory is outdated or I didn't understand the process, but is there tap water still in your engine? Shouldn't it be distilled water only in a 50/50 mix?

 

some people are not that **** about using distilled water in their cooling systems.. I use distilled water because I keep my trucks for a long time and do not want my cooling system to get corroded. I also use motor craft Gold...

 

The only tap water in my coolant system would be a small amount of residual left over from the flush.

I filled with coolant and distilled water.