That sucks you had to buy another radiator, but I'm glad you solved your issue.

 

OK guys. Stuck that 130 dollar radiator in today. I am able to drive 65 mph at 215 degress at about 2500rpm. Is this normal for a c4 / 302 combo? Or is there more to look into?

Thanks Ivan

 

Bad news. The second new rad is now overheating. There are still chunks of scale and rust coming out of the engine block and clogging the radiator. Short of tearing down the engine to hot tank the block, how can i get rid of this rust in the engine?

 

Get a 1.25 inch hose about 6 feet long. And get a 1.25 rubber cap. Get the flush and place it in the radiator. Follow the steps to the letter. Remove the hose on the tstat housing. Remove the tstat. Reinstall tstat housing without tstat. Install the 6 footer hose on the tstat housing. Pop the radiator cap install a garden hose. Install rubber cap on radiator. Turn on the hose full blast and sit in the car. Flush away till your stuff comes out clean. Trust me , remove the tstat. If not you get this little bit of dribble. Whatever comes out never returns.

http://www.youtube.com/watch?v=VIrK-N73qBc

 

Are you completely sure your thermostat isnt stuck open? cause it sure sounds like it is. I had a similar problem about a week ago, engine didnt overheat in town putting around, but after long extended drives on the highway it slowly climbed and climbed and eventually boiled over. It was because my thermostat was stuck open, thus not allowing coolant to get cooled down inside the radiator before it was flushed back into the engine, it was just constantly flowing which will, obviously, over time cause the coolant to overheat and thus engine overheats.

I just cant imagine THAT much rust coming out of your block. My radiator is 42 years old and still works fine even though it doesnt look so swell inside.

 

Yes, that much is coming out of the block/heads or both. After driving the car I can retrieve chunks of rust the size of small pebbles from the top side of the rad with a magnet. I can also see smaller bits accumulating in the rows. It's incredible. I've owned/worked on many classic cars of all types and never ran into this problem.

 

I have flushed many times already, sometimes for 30 mins. However, I have not tried flushing w/o thermostat out of car. I'll give it a shot.

 

You could install a filter that would go inbetween the engine and the radiator. It would trap the crap before it plugged the radiator. I installed one of these:
http://www.fasterjags.com/Tefba.html

when I installed a new aluminum radiator and it works. You could remove it after you were satisfied the rust and crap wasn't circulating anymore.