Cooling Path Clogged!!! Need suggestions Please

[SrS13]

I recently got a hold of a 1993 240sx Convertible for a good price but because it a had a blown head gasket. I'm currently in the process of changing it and discovered that the top of the cooling jackets on the blocks were clogged. The ones on the bad head gasket were completely sealed by rust as well. I opened up the engine block cooling paths with a razor blade but I am worried that the rust may be clogging this pathway from deeper inside the block.

I was wondering if anyone has encountered this before and if there is a way to make sure these pathways aren't clogged before I reassemble the engine.I searched and couldn't come up with anything useful.

[Wc240]

that is what happens when you dont do PM's and run straight water,rust. try to clean it out the best you can, carefully with a pipe cleaner, stuff like that. then rebuild it and imediatly do a coolant system flush, either with a hose or a flush machine, something that can build pressure inside the system