47-55.1 250 coolant sludge or hose lining breaking down?

[leegreen]

I had not thought of it being bacteria based.

I have some stuff to learn here....

"bacteria can live on glycol but not above 20%"
if that is true it is unlikely the cooling system could support any bacterial flourishing. At least in my ownership it would be closer to 50% and >20% would seem necessary for washington state

that said pictures of iron bacteria scaling in water pipes may be similar to what I have going on. Color matches but mine looks harder and less fluffy

I had some of the flakes in bleach overnight, it did not break down. But maybe flushing with bleach would be a good preventative measure in case there are bacteria spores.

[Hcb3200]

I am with you on the chemistry just not sure how long it had sat with water and less mixture of ingredients. And like you said was not fluffy. But thought I would throw it out there. It is perplexing but I am going to go with that hose makeup must not gel well (pun intended) with the flavor that was in there before. if it was located other places might think otherwise.