Draining Coolant Completely

[4RrDriver]

I have a 2004 V6. The previous owner put Dexcool in it, which is awful stuff. I want to drain it out, flush with distilled water, drain, then add Toyota Super Long Life. I will need to get out ALL of the water, since it gets very cold in my area and I can't afford to have the SLL diluted at all with water or it may freeze.

Do I really need to open the block drains? Or will removing the lower rad hose basically get all the old stuff out? Is it the lowest point in the system? Getting at the block drains looks difficult.

I'm wondering if I pour a bottle of coolant into the heater lines if that would sufficiently push out any residual water in the heater core, hoses and any water left in the lower parts of the block. The price of another jug of SLL seems cheap compared to the PITA of getting at those block drains...

Thoughts?

 

[Bradfsd]

I replaced the coolant in my 3rd gen last week with the red coolant. I did not remove the block drains as I felt is was unecessary. I drained all the coolant from valve at the bottom of the radiator. I then filled my radiator with distilled water and let it run for 15-20 minutes with the heater on high. I repeated this process until the water was mostly clear. Then fill it with OEM coolant. You can check the manual to see how much it holds. I am not a mechanic but found this fairly simple and I have not had any problems. Hope this helps.

 

[Bossman]

Toyota Factory Service Manual calls for you to loosen the 3 drain plugs on the engine and radiator, and drain the coolant.

http://4runnerclub.com/i/4r_files/f...07toyrm/1grfe/cooling/coolant_replacement.pdf

 

[jfry008]

Since the SLLC is only sold in 50/50 mixture, looks like you'll have to drain the engine block to get an absolute 50/50 mixture in the coolant system. Unless you want to flush 50/50 coolant through after flushing with water OR use a aftermarket full strength equivalent. If you use an aftermarket full strength equivalent you could flush the system with water, drain system, add half of the capacity with full strength coolant, then top off with water.

 

[4RrDriver]

I may as well play it safe and drain the block. My SLL is 55/44. If only they sold it in concentrate.

 

[RunnerAK]

You are correct that the V6 block drains are a serious pain to use, they require some serious arm/tool contortions to open and close. I drained the block on our V6 when I replaced the radiator and would never bother doing it again under normal circumstances, but since you have sketchy coolant in there, I'd play it safe and go through the trouble to drain it all out this time.