Last weekend, I went to look at another "well maintained" Explorer. When I looked in the overflow bottle, I saw little globules floating around. They were whitish/beigeish/light yellow (hard to tell exact color in green coolant) and appeared to be suspended as they weren't all floating at the top. I couldn't get my fingers on them. The closest thing that I could think of to compare them to in terms of color and size would be the clumps of yeast you sometimes get when using an ale yeast when making your homebrew. However, they did not rise to the surface and then fall down like ale yeast.

I took the radiator cap off and noticed some small silver particles that came up to the surface. I assume this was some of that aluma seal stuff. Needless to say, with the unidentified stuff in the cooling system plus all of the other issues, I walked away. It wasn't even worth making an offer. The seller thought he had a national treasure so no use arguing.

Anybody have any idea what those clumps in the overflow bottle might be?

 

In work we use a Safety Kleen Anti Freeze "Khameleon" thats suposed to mix with anything,It's yellow in color.T he owner proably used a similiar over the counter product. Your corect on the aluminum flakes,thats for leaks,radiator,heator core ,head gasket,about the same as useing BarsLeak.The lumps etc are proably the coolant mix binding with other contaminates in the cooling system that has been neglected.