I had to replace the filler hose between the filler spout and the tank on my 100 today so that I could get it to take gas at the station. This is the part number. The inside separates in the bend and closes off the hose.
I wanted to bring this thread back up again. I had the same thing happen on my 100 series at 185000 miles, it just started about 3 weeks ago and it would take 20 minutes to fill up. It only took about 15 minutes to replace. Here is a picture of the part number again.