Block cleaning?

[Evan Dutch]

Hopefully someone can help me out with some advice. I ordered a nice, new aluminum radiator for my 318 but I want to make sure I get the coolant passages in the block pretty clean that way I don’t ruin my new radiator. Any suggestions?

Thanks.

 

[rustycowll69]

I think there has been a few threads on this, you might try searching for some previous threads.
I've pulled the freeze plugs on the left side of the block, and found lots of rust, sand, etc accumulated in the bottom of the water jackets. Sometimes it's as deep as the top of the freeze plug holes! I used a garden hose with a spray handle and some wire coat hangers to poke the sediment loose and flush it out. It's a wet, cruddy job but you'd be surprised how much can come out of an old block, especially one that wasn't always maintained with proper coolant.