Pulled the head off my B230f engine. I noticed the water jackets were all plugged up. My question is this, was the head casted this way? Are these castings or are they clogged? I added a few photos and I hope they help out. Thanks

 

They are plugged up.

 

Aluminum does not rust, but it will corrode. I saw the same thing when I took my cylinder head off my b230.

The pic below shows a well prepped head, resurfaced. Look closely & U can discoloration at the places that are corroded on your cyl head.

I think it is caused by extra holes in head gasket.
Hopefully, more experienced & more knowledgeable members will chime in with experiences and results.




Not mine. Pulled this off the internet.