Cleaning build up in radiators

[jraynor]

Hello all,

It's been awhile for me since I've been on the forum, but I'm back with a lot of things going on.

So I've been working on the cooling system for awhile and I had to remove the radiators for some metal work to be done. So I'm tearing down the first one tonight and below is a picture of the end. This is the top of the radiator so it make sense that this has piled up at the ends. Is there a safe way to remove this build up and clean everything up? There's build up around each flute that will mostly chip off easily but I'd like to get it really clean

Also, this is the rebuilt one. The other is probably factory and I don't even want to imagine what it looks like yet

[luvrbus]

I use a mortar mixing tub from HD for 6 bucks and soak those overnight in white vinegar then hose it off then soak the tanks to remove any rust the vinegar enough to do it at Sam's Club will cost you about 15 bucks for 6 gals

[Scott & Heather]

You can also take them to a radiator repair shop and they might hot tank them. They will come out sparkly

[chessie4905]

Or... might need new core.