Originally Posted by kyle2020
before (Turns out the gunk was like gelled coolant / tissue cotten like stuff, had a nightmare cleaning it. Used a super soft toothbrush in the end, worked a damn treat
And after a through cleaning + a vinegar bath for 30 minutes:
Now my FuZion is clean (did a full block clean, barbs, o-rings and all) and my tubing / coolant and a few other odd bits are on their way, my new loop should be running by the weekend
It was gelled coolant. Most likely from somebody running a cheap coolant, or one of the Feser coolants/dyes.