Oops

, yes my car has a vacuum pot on the distributor. Thanks for the education!

Well if the radiator should be able to flow enough water to never back up out the filler then the radiator is definitly plugged up. Becuase if opened my spigot all the way when I was doing my expirement, water would start to overflow out of the radiator filler. It just couldn't handle the hose flow on full blast (I don't have very strong water pressure).
Bill, I hope you're right that I just need a "flush" or as Talkwrench says a "pressure flush". Are these services that any radiator shop will offer? Can anyone describe what is involved in these services? I'm always nervous that I'm going to pay $100 to have someone else run a hose through my radiator when I can do that at home for free. Do they use chemicals and a special machine or something?
Also Bill you say "flush the block". I know I asked about this before, but what is involved in the flushing the block? Just stick hose in the thermostat housing opening and run water through the engine and let it drain out the bottom (with the engine not running of course)? Do I use vinegar or something else?
Nate - Madison, Wisconsin 56 Ford Customline Sedan