fuglybutruns

I just want to double-check on this...
I think is is ok to mix the old honda green antifreeze with the new honda blue antifreeze. Is this right?
I know mixing old green antifreeze with some of the new gold antifreezes (inorganic with organic or vs versus) can create sludge, but I think the honda colors are compatible.
I've got an old 1994 civic that rarely gets driven and hasn't gotten an antifreeze change in at least 10 year. I saw the coolant reservoir is pretty low. As long as I'm filling it, I was going to drain the radiator too, which would change about 50% of the coolant. I don't want to monkey with the engine block drain plug or trying to get all the old coolant out. I figure changing half of it would help. Anyway, the dealer only had blue, but said it would mix just fine and not to worry.
So, has anyone mixed old green with new blue, and has there been any problems? Thanks for hopefully putting my mind at ease before I do this.

94EG8

You can mix them, they they are compatible. Or you can just run plain old green coolant available everywhere.

tony_2018

I don't remember Honda making any green Honda coolant. Thats news to me.

fuglybutruns

Thanks! I already bought a gallon of the blue 50/50 at the dealer. It's more than the autoparts store but I thought there might be some "secret sauce" in it that might help the car a little more. I also wasn't sure if putting in "generic" green was a good idea.
Anyway, I appreciate your confirmation! Thanks.

Jimi Hondrix

Sure is: the spunk from a thousand horny, rabid Japanese men.

94EG8

They did, it was a dark emerald green. You could still buy it here in Canada up until about a year ago.

Also, OP Beck/Arnley also sells the same blue Type II coolant for way less money. It's also 50/50 but at least it's by the gallon.

Jimi Hondrix

Most manufacturer's of green coolant clearly put on their labels "All Makes, All Models". Some even put safe for all cars including all Honda models.

http://g-ecx.images-amazon.com/image...328991493_.jpg

https://e2x3s6i4.ssl.hwcdn.net/main/...e/261-2090.jpg

http://ecx.images-amazon.com/images/...L._SL1500_.jpg

fuglybutruns

It could be that the "all-purpose green" antifreeze is safe for all engines if you first drain and clean out all the current old antifreeze out. I don't think these labels say "safe to mix with any other type of antifreeze". I am pretty sure if you mix inorganic and organic antifreeze it can lead to silicates precipitating out and other issues.
That said, I think the blue and green honda brand antifreeze are the same except the color, or are close enough. I just don't want to try to get all the green out. I just want to drain the green out of the radiator and refill the radiator to get half new and half old.
Thanks for all the input.

fuglybutruns

done! Had time this morning and did it. It was even easier than I thought it would be. Put a container under the radiator and unscrewed the drain plug. Let the radiator fully drain, and pulled the overfill container (which was already pretty low). I was amazed that about 3/4" of a gallon came out, since the manual says if you do a full drain including the engine you get .95 gallon. I didn't want to mess with the engine drain plug or needing to bleed or burp the engine. Anyway, I was very happy to get so much out. Tightened back up the radiator drain plug and filled up the radiator plus the overflow bottle with the new blue (which looked more like aqua to me). Crossed fingers and started the car. It worked. Drove over the the store and back. It still worked. Now I've got the green/blue mix with "mostly" new coolant.
Happy it was so easy.

TomCat39

Still need to burp the car. Anytime you drain and fill any part of the coolant system you introduce air pockets. Now that you have drove it, the pocket quite likely moved into the water jacket on the block.

You pop the rad cap to it's loosest setting and idle the car for 20+ minutes until the fan kicks on at least twice (I tend to go for 3 times myself). Shut the car off, take cap off and top up the radiator as necessary. Make sure the coolant recovery resevoir is to the max line and in the morning after the car cools off, you will need to top up the resevoir again as the rad will draw in more coolant.

You do this on level ground or with the nose of the car elevated (pointed up a hill/grade).

If you don't burp the car, you are likely to overheat one of these drives and you may cause yourself much more grief from a severe overheat then 20 minutes burping the car.

fuglybutruns

Wow. Thanks. I'm glad I posted. I wondered about burping the system but didn't see anything. I'll try what you suggested and see what happens. Thanks again!

fuglybutruns

Yikes. I looked at it this morning.
I took off the radiator cap and saw I needed to add more coolant. Plus the overflow tank that I had filled to the middle (half way between low and max) was empty. Gad zooks. There must have still been quite a bit of air trapped in the radiator after I thought I had filled it. And I was wondering what to do with the left over part of the gallon of antifreeze! Anyway, I added more this morning, but haven't had a chance to run the car or burp it. I still have some of the gallon left. Might have to wait to do the bleed though until tomorrow.