my carhas been run by the previous owner without coolant and this has caused a rather large amount of scale and rust to form in the block.

is it worth preassure flushing?
will it wreck any seals?
anything else i should know.

i've already tried to flush it out twice, no luck.
and i just opened the gas converter which was full of crap and rust.

hmmm i had the same problem, altho my head gasket blew as a result, and had been blown for quite a while, so yea was able to take the head off and give it a good clean, try cleaning it out with a pressure cleaner, puttin the same water back in, then putting some radiator cleaner in it, get it to norm operating temps just drivin round, come home, flush it all out n pressure clean it again, and all the gunk shud come out, and i reccomend gettin ur radiator block checked by a radiator company. then when its all clean some lovely new green stuff shud do great

i'm hoping head is ok as that was done by ford abt 40,000km ago for previous owner.
will be getting a new radiator.
thats why i was wondering if its worth getting a radiator place to do one of those preassure flushs.

will try what you say and see how see goes.