A very small bit of paper in the radiator may not present a problem. None in there is better than some.
Although the paper may break down into tiny bits, it can still help stop up a few flues. Especially those flues that already have limited capacity and thus make them even more inefficient. While the radiators are designed to have extra cooling capacity, why take a chance of limiting such over-capacity? Especially when it's an easy matter to take care of, i.e., fishing and reverse flushing. Read on.
I had the paper of a worn out radiator cap get into mine some time back and I knew it wasn't a good thing. I fished out what I could and then reverse flushed the radiator to get the rest out. I don't like anything in the radiator that's not designed to be in there. Accordingly, I recommend that any paper and such be removed as soon as practical.
Charlie
