I drove the car around for about a week. I made sure I looked at the radiator filler to see if it was working. I could not believe the rusty foam that came from it. I then flushed it out with that gun. Before I had overheating problems after I did not.
I do not think in my case it was a fix. It was a bandaid at best and I was able to run this season with no problems. I have noticed this week, I am getting some rust in the coolant, and it's time to do a better job. BTW you will get wet doing this.
You do not want to drain the radiator with all that crud floating on top. So I blasted it out of the filler. I used the heater hose to the engine which goes through the distribution tube and up to the top of the radiator. I then changed to different points to do a cross flush.