so i bought a reproduction radiator for my 1954 235 and it seems to be cooling fine because it hasnt moved yet and i only have a small fan pushing air through, but when it ran its first minute, this weird fibery cotton ball like crud appeared in the top tank. idk what is or where it came from but its clogged up quite a few of the cores and the last time i tried to clean it out it seemed like even more appeared. has this happened to anyone else and what would yall recommend i do? ive already taken it off and pushed water backwards through it but apparently it didnt work.
