Coolant discoloration 582 silver top

[Dunesand]

Hi Everyone,

My Raptor has a 582 silver top with about 340hrs on.
I don't fly a lot and it frequently happens that the trike stands for up to 3 months.
When flying, I am used to an ave coolant temp of 65deg as per Amptronic instrument.
Suddenly I noticed it shows 84deg on a cool overcast day but no loss of coolant or need to top up ever!!
I did drain and replace the coolant about 60 hrs(2 years) ago with Castrol's premix and at the time the coolant was clear and slightly colored as per usual.
So, after noticing the higher temp reading, I decided to drain the system. Please see the attached photos for the results.
The drained liquid is green and murky although, if hold against light, you do see a translucent pinkish color. Compared next to it is the premix straight from the Castrol container.
I've let it stand for a day but no sediment or anything formed at the bottom of the bottle.
Could it be that the Raptor's 2 radiators are connected with a piece of high pressure copper tubing at the bottom and that the copper reacts with the coolant?

I am rather worried and would appreciate any advise and comments.

Regards,
Hanno
Windhoek

[Dunesand]

Looks like I've discovered a first time phenomenon - am I a pioneer??

[Duck Rogers]

Looks like I've discovered a first time phenomenon - am I a pioneer??

Sorry Bud...........you're on your own

[Tailspin]

Looks like I've discovered a first time phenomenon - am I a pioneer??

Sorry Bud...........you're on your own

But if you do come up with a solution please share it as i am sure there will be some or other dude that will have a similar problem somewhere down the road.

[Kingfisher]

The green can be related to copper, but older radiators were all made from copper so this should not be a problem.
Look for anti freeze approved by Chevrolet, it is a high quality product. Got some from Autozone, can't remember
the name though, and keep to the mixing ratio suggested.