Is there a safe way to remove rust from a cooling system? It’s on a 1950 cadillac that’s all cast iron with a copper radiator. I’m pretty certain the coolant passages in the engine are plugged up from rust. I took off the rad hoses and rinsed everything out until it ran clear, but I’ve done this before and the car still runs hot.
A friend said really the only way is to take the freeze plugs out of the engine and rinse out all the caked up rust.