Quick Coolant flush question

[CanadianLurch]

Hi everyone, ive done some looking around and found that i should be using Toyota red coolant in my supra. I noticed in the resivoir that the coolant is in fact green not red! I am currently completing my 1jz engine swap so all of the fluids were drained and need to be replaced. My front clip didnt come with a rad so I am currently using my 7m rad until the koyo one i ordered comes in. Sorry for the background info now here is the questions
1. I followed the hayned manual for draining and running water through the rad until it comes out clean, and also disconnect the resivoir and clean thoroughly. I have read on the internet that you must also be sure to drain / flush the heater core as there may be green fluid left in there that would be disasterous if i added the new red fluid and it mixed. I am not sure how to do this or if i actually have to run the car with just water in it to flush it out?

Any input would be greatly appreciated thank you for your time

Steve

 

[Supracentral]

Everything you need to know about coolant is here:

http://www.mkiiitech.com/forum/showthread.php?p=4351#post4351

You've got a misconception. Specifically you don't need to run Toyota Red (it's excellent coolant) but there are other excellent options as well.

To flush the core, it's very easy - just disconnect the hoses at the VSV that go to the core and force water through it with a garden hose.

 

[jetjock]

Don't listen to that guy on the MKIIITech site. He's evil I tell ya....eeevil

Are you opening the block drain? There's lots of ways to flush, either with or without cleaning chemicals. You can flush just the core the way SC said, do a couple of fills and drains with the heater set to high during each run, or for a complete flush remove the thermostat, tie the heater valve open (or use a hand vacuum pump on it), and back flush through the upper radiator hose with the engine off and the lower hose disconnected. That's my preferred method after using chemicals. It also allow me to futher clean and flush the radiator separately, even removing it to clean the exterior surfaces, something that isn't done on most cars as often as it ought to be. After all, both hoses are already off.

All that said "disastrous" is a bit strong...

 

[CanadianLurch]

Thanks for the quick input boys. I have used the garden hose on the rad already but am not going to clean it now as in a week i have a brand new koyo aluminum coming in the mail. Any clues as to where the heater valve are? i will do some searching. also i have looked at that guys coolant thing and that is all fine and dandy but the shop that did the head gasket on the 7mgte (that was in previously in my car) did a poor job at that so im guessing they didnt use spec coolant. im going to go with the toyota red as i dont have very much mechanical expertise so have been using recommended fluids from other users (redline atf in tranny etc). Just to be sure i will be flushing the heater core as best possible.

thanks again