Changing coolant and no flush (1 Viewer)

[kimmron]

Hi Guys,
My car Landcruiser 80 1997. I have already posted a question on this issue and got answers. MANY THANKS TO ALL
I did not asked an adittional important question. If after changing the coolant fronm green to red i did not flush or the flush was not good and I drove around 400-500km could be that there is already something damaged?
What is most probable component/system to be damaged?
Is it possible to check and how potential damage that has been already caused?
Thanks a lot

 

[Rusty Marlin]

I doubt there would be damage. But you need to flush the system, then pick a coolant and stick to it.

 

[Marco Lau]

I blew my radiator on the Rubicon a few weeks back and at the time, i only had green coolant and my original coolant was red. I planned on flushing my cooling system once i get my radiator and fan sorted (I am still running a trail fix and it is fine for now) again. I think green will be better in the long run for availability reasons alone. I will be flushing my system with distilled water a few times before putting in 40/60 green mix.

 

[sunrk]

I don't fully understand the differences in chemistry between the various coolant types. In my cars it's green (Nulon green LLC) and the in the 80 it's red (Nulon red LLC). I know they are slightly chemically different (apart from the colour dye). Saab 'factory' coolant out of interest was blue.

I usually use a flush product when changing coolant, and run a hose through the motor for a while after until I get fully clear (to the eye) water out the convector (normally called 'radiator') drain port.

Coolants are like brake fluids. You have DOT-3 and DOT-4 but similar but different and DOT-5 which is very different. DOT-3 is what Toyota says to use for 80's. I don't know what later landcruiser models use.

 

[Kernal]

Kimmel: IME no direct damage should occur short term if you flush it out but what can happen is if the two different coolants were incompatible the mixture may form some sludge or sediment. You could flush the system using a mild cleaner followed by multiple water rinses, a couple using just distilled water, followed by your coolant of choice (generally a 50:50 mix of coolant and distilled water). Do not connect a water hose directly to the cooling system, too much pressure can cause leaks. Putting a hose loosely into the radiator or a top hose is OK however.
FWIW

 

[FJhammer]

My understanding is that the problem with mixing the green and red is the different corrosion inhibitor packages. Green coolants use a silicate based inhibitor that is suspended in the mixture. When Toyota introduced its long life coolant (red) it was an organic acid based inhibitor or OAT. they removed silicates and put in phosphates for aluminum protection. When you mix the two, the acid base in the red causes the silicates in the green to fall out of suspension which presents as a fine sand. This sand can congeal into a sludge and block passageways, damage seals, and cause pitting in the water pump.
In the past, I've done the conversion from green to red twice. I drained it and filled with 100% distilled water. Drove for about 10-15 minutes with the heater on high. Drained and filled with distilled water and added a coolant/radiator flush. Drove for about 10-15 minutes with the heater on high. Drained and filled with 100% distilled water, drove it etc. I ended up doing a total of 8 drain and fills before the water came out clear with no sediment. You'll go through about 15 gallons of distilled but it's gonna be clean. Then add the coolant of your choice. Find one with an inhibitor package that best suits for needs. Japanese manufacturers really don't like products with DexCool because it contains 2-EHA which is a plasticizer. Toyota red is a good option however, it might not be a good idea if you're running an aftermarket radiator with lead soldering as tests have apparently shown its corrosive to the solder.